https://www.marinespecies.org/r/api.php?action=feedcontributions&user=Wouter+Kreiken&feedformat=atom
MarineSpecies Traits Wiki - User contributions [en]
2024-03-29T02:07:58Z
User contributions
MediaWiki 1.31.7
https://www.marinespecies.org/r/index.php?title=Main_Page&diff=35030
Main Page
2009-10-06T07:47:52Z
<p>Wouter Kreiken: Marine Plankton</p>
<hr />
<div><!----------------------------Introduction-----------------><br />
{| style="width:100%; border:1px solid #23297A; margin:0em 0em 0em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
|align="top"|<br />
<div style="font-size:100%; padding-bottom:0.15em;">Welcome to the [[Coastal Wiki]] an Internet encyclopaedia of [[Special:Statistics|{{NUMBEROFARTICLES}}]] information pages for and by coastal professionals providing up-to-date high quality Coastal and Marine information. [[Coastal Wiki:Why, What and for Whom?|More about the Coastal Wiki]]</div><br />
|}<br />
<!----------------------End of introduction-----------------><br />
<br />
<!-----------------------Today's featured article, Did you know--------------------><br />
{|style="border-spacing:8px; margin:0px -8px;"<br />
|class="MainPageBG" style="width:70%; border:1px solid #23297A; background:#f5faff; vertical-align:top; color:#000;"|<br />
{|width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">This months featured article</h2><br />
|-<br />
|style="color:#000;"| <br />
<br />
{{Template:This_weeks_featured_article}} [[Marine Plankton|'''More..''']]<br />
<br />
|-<br />
! <br />
|-<br />
|}<!----------------------------------Categories---------------------><br />
|class="MainPageBG" style="width:30%; border:1px solid #23297A; background:#f5faff; vertical-align:top"|<br />
{| width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
!<br />
<br />
<h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">Categories</h2><br />
|-<br />
|-<br />
|style="width:15em; vertical-align:right; font-weight:bold;"|<br />
[[Image:earth_bis.gif|earth2.gif]] [[:Category:Coastal and marine areas and locations|Areas and locations]]<br><br><br />
[[Image:human_bis.gif|human4.gif]] [[:Category:Coastal and marine human activities|Human activities]]<br />
<br><br><br />
[[Image:impacts_bis.gif|impacts.gif]] [[:Category:Coastal and marine issues and impacts|Issues and impacts]]<br><br><br />
[[Image:natural_bis.gif|natural.gif]] [[:Category:Coastal and marine natural environment|Natural environment]]<br><br><br />
[[Image:management-bis.gif|Management.gif]] [[:Category:Coastal management|Coastal management]]<br />
<br><br><br />
[[Image:people_bis.gif|people.gif]] [[:Category:People and organisations in coastal management|People and organisations ]] <br />
|}<br />
|}<br />
{{#categorytree:Coastal and marine system|mode=pages|style=border:1px solid #23297A; padding:0.7ex; vertical-align:right; background-color:#f5faff;}}<br />
<br><br />
'''Welcome to the Coastal Wiki, your guide to coastal knowledge and experience'''<br><br />
You may find information on any coastal topic by entering a corresponding term in the search window. “Go” will direct you to an article with this title (if such an article exists); “Search” will provide an overview of articles in which your search term appears. You will find an explanation of coastal terms and concepts in the [[Glossary]].<br />
<br />
We also invite coastal and marine practitioners, policymakers and scientists to make a contribution to this new concept in sharing European knowledge and experience in integrated coastal zone management. You may contribute in several ways: you may improve or update an existing article, you may add a discussion page to an existing article or you may add a new topic.<br />
<br><br><br />
<br />
'''How to contribute to the Coastal Wiki'''<br><br />
You have unrestricted access to the Coastal Wiki. But for adding or editing articles an authorisation is required. This is a major difference with the general wikipedia. For obtaining an editing authorisation you may contact your [http://www.encora.eu/networks.php national coordination office] or you may simply send an email to info@encora.eu. You will receive a request to provide contact information for the Wiki Contact Database. Anonymous contributions to the Coastal Wiki are precluded. Authors, co-authors and editors of articles are explicitly acknowledged. Your contribution will be reviewed by the coordinator of the theme where your article best fits. The theme coordinators also check that your contribution is [[links|adequately linked]] to existing articles on similar or related topics. <br />
<br />
You should remember that the Coastal Wiki is primarily meant for disseminating knowledge to a broader audience than the circles of specialists working at the frontiers of science. It is not meant for publishing original research; it is a vehicle for disseminating knowledge complementary to the traditional peer-reviewed scientific journals. Please read the [[Basic setup, rules and guidelines]] and [[How to edit an article]] before you start writing an article.<br />
<br><br><br />
<br><br />
<!------------------------------Bottom table---------------------><br />
{| style=" width:100%; border:1px solid #23297A; margin:0em 0em 1em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
<br />
|style="width:25%"| [[Help:Contents|'''Help pages''']] <br />
|style="width:25%"|[[glossary|'''Glossary''']] <br />
|style="width:25%"| [[Special:Popularpages|'''Popular pages''']] <br />
|style="width:25%" align="right"| [[Articles that need expanding|'''Articles that need expanding''']]<br />
<br />
|}<br />
<!------------------------------end of Bottom table---------------------></div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Template:This_weeks_featured_article&diff=35029
Template:This weeks featured article
2009-10-06T07:47:10Z
<p>Wouter Kreiken: Marine Plankton</p>
<hr />
<div>==Marine Plankton==<br />
<br />
[[Image:coscinodiscuswailesii_pnw.jpg|thumb|left|250px|''The diatom'' Coscinodiscus wailesii. ''The two ‘valves’ of the cell can be seen in the top left image. Image taken by M. Hoppenrath, provided courtesy of Plankton*Net (image # 12641) <ref name = "Plankton Net"> Plankton Net; Data Provider at the Alfred Wegener Insitute for Polar and Marine Research: http://planktonnet.awi.de/</ref>.'']]<br />
<br />
[[Plankton]] consists of a diverse range of living organisms that spend at least a part of their life cycle suspended in water. The term [[plankton]] is actually a Greek word, meaning ''that which is made to wander or drift''. This term is further divided into the [[phytoplankton]] and [[zooplankton]], meaning plant- (Gk. ''phyto'') and animal- (Gk. ''zoön'') drifters respectively. <br />
<br />
Planktonic organisms may have a limited ability to control their fine-scale distribution in the water column, but are otherwise at the mercy of oceanic currents and water movements. Holoplantkon refers to those organisms that spend their entire life in the plankton, as opposed to the meroplantkon, which are only planktonic for a part of their lives. Organisms that are capable of resisting the powers of currents, such as fish and squid, are referred to as neckton. <br />
<br />
Planktonic organisms are typically classified into broad size categories according to the ''' ‘Sieburth-scale’ ''', originally proposed in 1978. Viruses and jelly fish sit at opposite ends of this scale, which runs from fractions of a millimetre to metres.</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Main_Page&diff=33820
Main Page
2009-09-01T13:01:12Z
<p>Wouter Kreiken: Coastal Hydrodynamics And Transport Processes</p>
<hr />
<div><!----------------------------Introduction-----------------><br />
{| style="width:100%; border:1px solid #23297A; margin:0em 0em 0em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
|align="top"|<br />
<div style="font-size:100%; padding-bottom:0.15em;">Welcome to the [[Coastal Wiki]] an Internet encyclopaedia of [[Special:Statistics|{{NUMBEROFARTICLES}}]] information pages for and by coastal professionals providing up-to-date high quality Coastal and Marine information. [[Coastal Wiki:Why, What and for Whom?|More about the Coastal Wiki]]</div><br />
|}<br />
<!----------------------End of introduction-----------------><br />
<br />
<!-----------------------Today's featured article, Did you know--------------------><br />
{|style="border-spacing:8px; margin:0px -8px;"<br />
|class="MainPageBG" style="width:70%; border:1px solid #23297A; background:#f5faff; vertical-align:top; color:#000;"|<br />
{|width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">This months featured article</h2><br />
|-<br />
|style="color:#000;"| <br />
<br />
{{Template:This_weeks_featured_article}} [[Coastal Hydrodynamics And Transport Processes|'''More..''']]<br />
<br />
|-<br />
! <br />
|-<br />
|}<!----------------------------------Categories---------------------><br />
|class="MainPageBG" style="width:30%; border:1px solid #23297A; background:#f5faff; vertical-align:top"|<br />
{| width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
!<br />
<br />
<h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">Categories</h2><br />
|-<br />
|-<br />
|style="width:15em; vertical-align:right; font-weight:bold;"|<br />
[[Image:earth_bis.gif|earth2.gif]] [[:Category:Coastal and marine areas and locations|Areas and locations]]<br><br><br />
[[Image:human_bis.gif|human4.gif]] [[:Category:Coastal and marine human activities|Human activities]]<br />
<br><br><br />
[[Image:impacts_bis.gif|impacts.gif]] [[:Category:Coastal and marine issues and impacts|Issues and impacts]]<br><br><br />
[[Image:natural_bis.gif|natural.gif]] [[:Category:Coastal and marine natural environment|Natural environment]]<br><br><br />
[[Image:management-bis.gif|Management.gif]] [[:Category:Coastal management|Coastal management]]<br />
<br><br><br />
[[Image:people_bis.gif|people.gif]] [[:Category:People and organisations in coastal management|People and organisations ]] <br />
|}<br />
|}<br />
{{#categorytree:Coastal and marine system|mode=pages|style=border:1px solid #23297A; padding:0.7ex; vertical-align:right; background-color:#f5faff;}}<br />
<br><br />
'''Welcome to the Coastal Wiki, your guide to coastal knowledge and experience'''<br><br />
You may find information on any coastal topic by entering a corresponding term in the search window. “Go” will direct you to an article with this title (if such an article exists); “Search” will provide an overview of articles in which your search term appears. You will find an explanation of coastal terms and concepts in the [[Glossary]].<br />
<br />
We also invite coastal and marine practitioners, policymakers and scientists to make a contribution to this new concept in sharing European knowledge and experience in integrated coastal zone management. You may contribute in several ways: you may improve or update an existing article, you may add a discussion page to an existing article or you may add a new topic.<br />
<br><br><br />
<br />
'''How to contribute to the Coastal Wiki'''<br><br />
You have unrestricted access to the Coastal Wiki. But for adding or editing articles an authorisation is required. This is a major difference with the general wikipedia. For obtaining an editing authorisation you may contact your [http://www.encora.eu/networks.php national coordination office] or you may simply send an email to info@encora.eu. You will receive a request to provide contact information for the Wiki Contact Database. Anonymous contributions to the Coastal Wiki are precluded. Authors, co-authors and editors of articles are explicitly acknowledged. Your contribution will be reviewed by the coordinator of the theme where your article best fits. The theme coordinators also check that your contribution is [[links|adequately linked]] to existing articles on similar or related topics. <br />
<br />
You should remember that the Coastal Wiki is primarily meant for disseminating knowledge to a broader audience than the circles of specialists working at the frontiers of science. It is not meant for publishing original research; it is a vehicle for disseminating knowledge complementary to the traditional peer-reviewed scientific journals. Please read the [[Basic setup, rules and guidelines]] and [[How to edit an article]] before you start writing an article.<br />
<br><br><br />
<br><br />
<!------------------------------Bottom table---------------------><br />
{| style=" width:100%; border:1px solid #23297A; margin:0em 0em 1em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
<br />
|style="width:25%"| [[Help:Contents|'''Help pages''']] <br />
|style="width:25%"|[[glossary|'''Glossary''']] <br />
|style="width:25%"| [[Special:Popularpages|'''Popular pages''']] <br />
|style="width:25%" align="right"| [[Articles that need expanding|'''Articles that need expanding''']]<br />
<br />
|}<br />
<!------------------------------end of Bottom table---------------------></div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Template:This_weeks_featured_article&diff=33819
Template:This weeks featured article
2009-09-01T13:00:39Z
<p>Wouter Kreiken: Coastal Hydrodynamics And Transport Processes</p>
<hr />
<div>==Coastal Hydrodynamics And Transport Processes==<br />
<br />
[[Image:tombolo2.jpg|thumb|300px|right|Tombolo formation behind coastal breakwater, an example of the result of coastal transport processes]]<br />
<br />
The hydrodynamic conditions or processes, that come about from [[Tidal wave|waves]] transforming over a coastal profile and generating wave set up and [[Longshore current|longshore currents]], will result in movement and transport of the sediments (e.g. sand) present in the profile. This is referred to as ''littoral transport processes'' and is the main subject of this article. However, transport of fine sediments will also be discussed, but only very briefly.<br />
<br />
The sediment on the seabed is transported when it is exposed to large enough forces, or ''shear stresses'', by the water movements. These movements can be caused by the current or by the wave orbital velocities or a combination of both, the latter being the most important situation. The relevant parameters for the description of the sediment transport along a shoreline or in a coastal area are therefore the following:<br />
<br />
*The wave conditions at the site and the possible variations over the site plus the adjoining areas<br />
*The current conditions as well as the variations of these over the area <br />
*The water-level conditions, i.e. tide, storm surge and wave set-up<br />
*The [[bathymetry]] (the depth variations) in the area <br />
*The [[sediment]] characteristics over the area <br />
*The sources and sinks of sediment, such as rivers, eroding coasts or tidal inlets</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=ENCORA_portal&diff=32935
ENCORA portal
2009-08-18T10:13:52Z
<p>Wouter Kreiken: ENCORA portal created</p>
<hr />
<div><!------------------------------10 themes-----------------> <br />
{|border=1 style="border:2px #23297A solid; background:#f5faff;" width="688px" cellspacing="0" cellpadding="0" <br />
|cellspacing="0" style="border-bottom:1px solid #23297A; background:#cee0f2; font-size:150%" colspan=2 align=center height=30px|Encora Themes <br />
|- <br />
| <br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100% <br />
|-valign="top" <br />
|width="100px" valign="top" style="border-right:1px solid #23297A"|[[Image:Theme01_40.png|Theme 1 : Social and economic aspects of ICZM Multifunctionality and Valuation.]]|| <br />
'''[[Theme 1]] - Social and economic aspects of ICZM Multifunctionality and Valuation.'''<br> <br />
Valuation of competing functions to optimise the societal use of coastal and marine resources. <br />
|} <br />
<br />
| <br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100% <br />
|-valign="top" <br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme02_40.png|Theme 2 : ICZM Participation and Implementation.]]|| <br />
'''[[Theme 2]] - ICZM Participation and Implementation.''' <br> <br />
Testing and improving methods to evaluate progress in the implementation of ICZM, including eGovernance. <br> <br />
|} <br />
|- <br />
| <br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100% <br />
|-valign="top" <br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme03_40.png|Theme 3 : Coastal and marine spatial planning.]]|| <br />
'''[[Theme 3]] - Coastal and marine spatial planning.''' <br> <br />
Multiple-scale structuring of spatial coastal and marine planning and related decision-support systems for sustainable development. <br> <br />
|} <br />
| <br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100% <br />
|-valign="top" <br />
|width="102px" valign=center style="border-right:1px solid #23297A"|[[Image:Theme04_40.png|Theme 4 : Pollution, prevention and mitigation.]]|| <br />
'''[[Theme 4]] - Pollution, prevention and mitigation.''' <br> <br />
Development and application of emerging methodologies for preventing, detecting and mitigating pollution and for identification of areas at risk. <br> <br />
|} <br />
|- <br />
| <br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100% <br />
|-valign="top" <br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme05_40.png|Theme 5 : Long-term geomorphological change and climate impacts.]]|| <br />
'''[[Theme 5]] - Long-term geomorphological change and climate impacts.'''<br> <br />
Promoting development, demonstration & dissemination of new and emerging models & methodologies for prediction of changes to coastal systems.<br> <br />
|} <br />
| <br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100% <br />
|-valign="top" <br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme06_40.png| Theme 6 : Effect of development and use on eco-morphology and coastal habitats.]]|| <br />
'''[[Theme 6]] - Effect of development and use on eco-morphology and coastal habitats.'''<br> <br />
Impact-assessment tools and environmental techniques for recovery of coastal habitats.<br> <br />
|} <br />
|- <br />
| <br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100% <br />
|-valign="top" <br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme07_40.png|Theme 7|Theme 7 Biodiversity of coastal and marine habitats and ecosystems]]|| <br />
'''[[Theme 7 Biodiversity of coastal and marine habitats and ecosystems|Theme 7]] - Assessment of biodiversity change.''' <br> <br />
Testing and improving an ecological valuation protocol for the coastal and marine environment, including transitional waters. <br> <br />
|} <br />
| <br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100% <br />
|-valign="top" <br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme08_40.png|Theme 8 : New sustainable coastal engineering techniques.]]|| <br />
'''[[Theme 8]] - New sustainable coastal engineering techniques.''' <br> <br />
Cataloguing innovative coastal engineering techniques to solve practical coastal protection issues. <br> <br />
|} <br />
|- <br />
| <br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100% <br />
|-valign="top" <br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme09_40.png|Theme 9 : Assessment of field observation techniques.]]|| <br />
'''[[Theme 9]] - Assessment of field observation techniques.''' <br> <br />
New and emerging tools and practices for coastal and marine observation, with focus on remote sensing and remotely controlled measuring devices. <br> <br />
|} <br />
| <br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100% <br />
|-valign="top" <br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme10_40.png| Theme 10 : Capacity Building, Training and Education.]]|| <br />
'''[[Theme 10]] - Capacity Building, Training and Education. ''' <br> <br />
Comparative assessment of ICZM training and education programmes. <br> <br />
|} <br />
|} <br />
<!------------------------------end of 10 themes-----------------></div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Main_Page&diff=32475
Main Page
2009-08-06T13:10:30Z
<p>Wouter Kreiken: </p>
<hr />
<div><!----------------------------Introduction-----------------><br />
{| style="width:100%; border:1px solid #23297A; margin:0em 0em 0em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
|align="top"|<br />
<div style="font-size:100%; padding-bottom:0.15em;">Welcome to the [[Coastal Wiki]] an Internet encyclopaedia of [[Special:Statistics|{{NUMBEROFARTICLES}}]] information pages for and by coastal professionals providing up-to-date high quality Coastal and Marine information. [[Coastal Wiki:Why, What and for Whom?|More about the Coastal Wiki]]</div><br />
|}<br />
<!----------------------End of introduction-----------------><br />
<br />
<!-----------------------Today's featured article, Did you know--------------------><br />
{|style="border-spacing:8px; margin:0px -8px;"<br />
|class="MainPageBG" style="width:70%; border:1px solid #23297A; background:#f5faff; vertical-align:top; color:#000;"|<br />
{|width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">This months featured article</h2><br />
|-<br />
|style="color:#000;"| <br />
<br />
{{Template:This_weeks_featured_article}} [[The Blue Book|'''More..''']]<br />
<br />
|-<br />
! <br />
|-<br />
|}<!----------------------------------Categories---------------------><br />
|class="MainPageBG" style="width:30%; border:1px solid #23297A; background:#f5faff; vertical-align:top"|<br />
{| width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
!<br />
<br />
<h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">Categories</h2><br />
|-<br />
|-<br />
|style="width:15em; vertical-align:right; font-weight:bold;"|<br />
[[Image:earth_bis.gif|earth2.gif]] [[:Category:Coastal and marine areas and locations|Areas and locations]]<br><br><br />
[[Image:human_bis.gif|human4.gif]] [[:Category:Coastal and marine human activities|Human activities]]<br />
<br><br><br />
[[Image:impacts_bis.gif|impacts.gif]] [[:Category:Coastal and marine issues and impacts|Issues and impacts]]<br><br><br />
[[Image:natural_bis.gif|natural.gif]] [[:Category:Coastal and marine natural environment|Natural environment]]<br><br><br />
[[Image:management-bis.gif|Management.gif]] [[:Category:Coastal management|Coastal management]]<br />
<br><br><br />
[[Image:people_bis.gif|people.gif]] [[:Category:People and organisations in coastal management|People and organisations ]] <br />
|}<br />
|}<br />
{{#categorytree:Coastal and marine system|mode=pages|style=border:1px solid #23297A; padding:0.7ex; vertical-align:right; background-color:#f5faff;}}<br />
<br><br />
'''Welcome to the Coastal Wiki, your guide to coastal knowledge and experience'''<br><br />
You may find information on any coastal topic by entering a corresponding term in the search window. “Go” will direct you to an article with this title (if such an article exists); “Search” will provide an overview of articles in which your search term appears. You will find an explanation of coastal terms and concepts in the [[Glossary]].<br />
<br />
We also invite coastal and marine practitioners, policymakers and scientists to make a contribution to this new concept in sharing European knowledge and experience in integrated coastal zone management. You may contribute in several ways: you may improve or update an existing article, you may add a discussion page to an existing article or you may add a new topic.<br />
<br><br><br />
<br />
'''How to contribute to the Coastal Wiki'''<br><br />
You have unrestricted access to the Coastal Wiki. But for adding or editing articles an authorisation is required. This is a major difference with the general wikipedia. For obtaining an editing authorisation you may contact your [http://www.encora.eu/networks.php national coordination office] or you may simply send an email to info@encora.eu. You will receive a request to provide contact information for the Wiki Contact Database. Anonymous contributions to the Coastal Wiki are precluded. Authors, co-authors and editors of articles are explicitly acknowledged. Your contribution will be reviewed by the coordinator of the theme where your article best fits. The theme coordinators also check that your contribution is [[links|adequately linked]] to existing articles on similar or related topics. <br />
<br />
You should remember that the Coastal Wiki is primarily meant for disseminating knowledge to a broader audience than the circles of specialists working at the frontiers of science. It is not meant for publishing original research; it is a vehicle for disseminating knowledge complementary to the traditional peer-reviewed scientific journals. Please read the [[Basic setup, rules and guidelines]] and [[How to edit an article]] before you start writing an article.<br />
<br><br><br />
<br><br />
<!------------------------------Bottom table---------------------><br />
{| style=" width:100%; border:1px solid #23297A; margin:0em 0em 1em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
<br />
|style="width:25%"| [[Help:Contents|'''Help pages''']] <br />
|style="width:25%"|[[glossary|'''Glossary''']] <br />
|style="width:25%"| [[Special:Popularpages|'''Popular pages''']] <br />
|style="width:25%" align="right"| [[Articles that need expanding|'''Articles that need expanding''']]<br />
<br />
|}<br />
<!------------------------------end of Bottom table---------------------></div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Main_Page&diff=32474
Main Page
2009-08-06T13:07:28Z
<p>Wouter Kreiken: reordered categoty icons on main page</p>
<hr />
<div><!----------------------------Introduction-----------------><br />
{| style="width:100%; border:1px solid #23297A; margin:0em 0em 0em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
|align="top"|<br />
<div style="font-size:100%; padding-bottom:0.15em;">Welcome to the [[Coastal Wiki]] an Internet encyclopaedia of [[Special:Statistics|{{NUMBEROFARTICLES}}]] information pages for and by coastal professionals providing up-to-date high quality Coastal and Marine information. [[Coastal Wiki:Why, What and for Whom?|More about the Coastal Wiki]]</div><br />
|}<br />
<!----------------------End of introduction-----------------><br />
<br />
<!-----------------------Today's featured article, Did you know--------------------><br />
{|style="border-spacing:8px; margin:0px -8px;"<br />
|class="MainPageBG" style="width:70%; border:1px solid #23297A; background:#f5faff; vertical-align:top; color:#000;"|<br />
{|width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">This months featured article</h2><br />
|-<br />
|style="color:#000;"| <br />
<br />
{{Template:This_weeks_featured_article}} [[The Blue Book|'''More..''']]<br />
<br />
|-<br />
! <br />
|-<br />
|}<!----------------------------------Categories---------------------><br />
|class="MainPageBG" style="width:30%; border:1px solid #23297A; background:#f5faff; vertical-align:top"|<br />
{| width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
!<br />
<br />
<h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">Categories</h2><br />
|-<br />
|-<br />
|style="width:15em; vertical-align:right; font-weight:bold;"|<br />
[[Image:earth_bis.gif|earth2.gif]] [[:Category:Coastal and marine areas and locations|Areas and locations]]<br><br><br />
[[Image:human_bis.gif|human4.gif]] [[:Category:Coastal and marine human activities|Human activities]]<br />
<br><br><br />
[[Image:impacts_bis.gif|impacts.gif]] [[:Category:Coastal and marine issues and impacts|Issues and impacts]]<br><br><br />
[[Image:natural_bis.gif|natural.gif]] [[:Category:Coastal and marine natural environment|Natural environment]]<br><br><br />
[[Image:management-bis.gif|Management.gif]] [[:Category:Coastal management|Coastal management]]<br />
<br><br><br />
[[Image:people_bis.gif|people.gif]] [[:Category:People and organisations in coastal management|People and organisations ]] <br />
|}<br />
|}<br />
{{#categorytree:Coastal and marine system|mode=pages|style=border:1px solid gray; padding:0.7ex; vertical-align:right; background-color:#f5faff;}}<br />
<br><br />
'''Welcome to the Coastal Wiki, your guide to coastal knowledge and experience'''<br><br />
You may find information on any coastal topic by entering a corresponding term in the search window. “Go” will direct you to an article with this title (if such an article exists); “Search” will provide an overview of articles in which your search term appears. You will find an explanation of coastal terms and concepts in the [[Glossary]].<br />
<br />
We also invite coastal and marine practitioners, policymakers and scientists to make a contribution to this new concept in sharing European knowledge and experience in integrated coastal zone management. You may contribute in several ways: you may improve or update an existing article, you may add a discussion page to an existing article or you may add a new topic.<br />
<br><br><br />
<br />
'''How to contribute to the Coastal Wiki'''<br><br />
You have unrestricted access to the Coastal Wiki. But for adding or editing articles an authorisation is required. This is a major difference with the general wikipedia. For obtaining an editing authorisation you may contact your [http://www.encora.eu/networks.php national coordination office] or you may simply send an email to info@encora.eu. You will receive a request to provide contact information for the Wiki Contact Database. Anonymous contributions to the Coastal Wiki are precluded. Authors, co-authors and editors of articles are explicitly acknowledged. Your contribution will be reviewed by the coordinator of the theme where your article best fits. The theme coordinators also check that your contribution is [[links|adequately linked]] to existing articles on similar or related topics. <br />
<br />
You should remember that the Coastal Wiki is primarily meant for disseminating knowledge to a broader audience than the circles of specialists working at the frontiers of science. It is not meant for publishing original research; it is a vehicle for disseminating knowledge complementary to the traditional peer-reviewed scientific journals. Please read the [[Basic setup, rules and guidelines]] and [[How to edit an article]] before you start writing an article.<br />
<br><br><br />
<br><br />
<!------------------------------Bottom table---------------------><br />
{| style=" width:100%; border:1px solid #23297A; margin:0em 0em 1em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
<br />
|style="width:25%"| [[Help:Contents|'''Help pages''']] <br />
|style="width:25%"|[[glossary|'''Glossary''']] <br />
|style="width:25%"| [[Special:Popularpages|'''Popular pages''']] <br />
|style="width:25%" align="right"| [[Articles that need expanding|'''Articles that need expanding''']]<br />
<br />
|}<br />
<!------------------------------end of Bottom table---------------------></div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Main_Page&diff=32472
Main Page
2009-08-06T13:04:02Z
<p>Wouter Kreiken: category tree expanded</p>
<hr />
<div><!----------------------------Introduction-----------------><br />
{| style="width:100%; border:1px solid #23297A; margin:0em 0em 0em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
|align="top"|<br />
<div style="font-size:100%; padding-bottom:0.15em;">Welcome to the [[Coastal Wiki]] an Internet encyclopaedia of [[Special:Statistics|{{NUMBEROFARTICLES}}]] information pages for and by coastal professionals providing up-to-date high quality Coastal and Marine information. [[Coastal Wiki:Why, What and for Whom?|More about the Coastal Wiki]]</div><br />
|}<br />
<!----------------------End of introduction-----------------><br />
<br />
<!-----------------------Today's featured article, Did you know--------------------><br />
{|style="border-spacing:8px; margin:0px -8px;"<br />
|class="MainPageBG" style="width:70%; border:1px solid #23297A; background:#f5faff; vertical-align:top; color:#000;"|<br />
{|width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">This months featured article</h2><br />
|-<br />
|style="color:#000;"| <br />
<br />
{{Template:This_weeks_featured_article}} [[The Blue Book|'''More..''']]<br />
<br />
|-<br />
! <br />
|-<br />
|}<!----------------------------------Categories---------------------><br />
|class="MainPageBG" style="width:30%; border:1px solid #23297A; background:#f5faff; vertical-align:top"|<br />
{| width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
!<br />
<br />
<h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">Categories</h2><br />
|-<br />
|-<br />
|style="width:15em; vertical-align:right; font-weight:bold;"|<br />
[[Image:natural_bis.gif|natural.gif]] [[:Category:Coastal and marine natural environment|Natural environment]]<br><br><br />
[[Image:human_bis.gif|human4.gif]] [[:Category:Coastal and marine human activities|Human activities]]<br><br><br />
[[Image:impacts_bis.gif|impacts.gif]] [[:Category:Coastal and marine issues and impacts|Issues and impacts]]<br><br><br />
[[Image:earth_bis.gif|earth2.gif]] [[:Category:Coastal and marine areas and locations|Areas and locations]]<br><br><br />
[[Image:management-bis.gif|Management.gif]] [[:Category:Coastal management|Coastal management]]<br><br><br />
[[Image:people_bis.gif|people.gif]] [[:Category:People and organisations in coastal management|People and organisations ]] <br />
|}<br />
|}<br />
{{#categorytree:Coastal and marine system|mode=pages|style=border:1px solid gray; padding:0.7ex; vertical-align:right; background-color:#f5faff;}}<br />
<br><br />
'''Welcome to the Coastal Wiki, your guide to coastal knowledge and experience'''<br><br />
You may find information on any coastal topic by entering a corresponding term in the search window. “Go” will direct you to an article with this title (if such an article exists); “Search” will provide an overview of articles in which your search term appears. You will find an explanation of coastal terms and concepts in the [[Glossary]].<br />
<br />
We also invite coastal and marine practitioners, policymakers and scientists to make a contribution to this new concept in sharing European knowledge and experience in integrated coastal zone management. You may contribute in several ways: you may improve or update an existing article, you may add a discussion page to an existing article or you may add a new topic.<br />
<br><br><br />
<br />
'''How to contribute to the Coastal Wiki'''<br><br />
You have unrestricted access to the Coastal Wiki. But for adding or editing articles an authorisation is required. This is a major difference with the general wikipedia. For obtaining an editing authorisation you may contact your [http://www.encora.eu/networks.php national coordination office] or you may simply send an email to info@encora.eu. You will receive a request to provide contact information for the Wiki Contact Database. Anonymous contributions to the Coastal Wiki are precluded. Authors, co-authors and editors of articles are explicitly acknowledged. Your contribution will be reviewed by the coordinator of the theme where your article best fits. The theme coordinators also check that your contribution is [[links|adequately linked]] to existing articles on similar or related topics. <br />
<br />
You should remember that the Coastal Wiki is primarily meant for disseminating knowledge to a broader audience than the circles of specialists working at the frontiers of science. It is not meant for publishing original research; it is a vehicle for disseminating knowledge complementary to the traditional peer-reviewed scientific journals. Please read the [[Basic setup, rules and guidelines]] and [[How to edit an article]] before you start writing an article.<br />
<br><br><br />
<br><br />
<!------------------------------Bottom table---------------------><br />
{| style=" width:100%; border:1px solid #23297A; margin:0em 0em 1em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
<br />
|style="width:25%"| [[Help:Contents|'''Help pages''']] <br />
|style="width:25%"|[[glossary|'''Glossary''']] <br />
|style="width:25%"| [[Special:Popularpages|'''Popular pages''']] <br />
|style="width:25%" align="right"| [[Articles that need expanding|'''Articles that need expanding''']]<br />
<br />
|}<br />
<!------------------------------end of Bottom table---------------------></div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Main_Page&diff=32471
Main Page
2009-08-06T13:01:50Z
<p>Wouter Kreiken: introduction banner</p>
<hr />
<div><!----------------------------Introduction-----------------><br />
{| style="width:100%; border:1px solid #23297A; margin:0em 0em 0em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
|align="top"|<br />
<div style="font-size:100%; padding-bottom:0.15em;">Welcome to the [[Coastal Wiki]] an Internet encyclopaedia of [[Special:Statistics|{{NUMBEROFARTICLES}}]] information pages for and by coastal professionals providing up-to-date high quality Coastal and Marine information. [[Coastal Wiki:Why, What and for Whom?|More about the Coastal Wiki]]</div><br />
|}<br />
<!----------------------End of introduction-----------------><br />
<br />
<!-----------------------Today's featured article, Did you know--------------------><br />
{|style="border-spacing:8px; margin:0px -8px;"<br />
|class="MainPageBG" style="width:70%; border:1px solid #23297A; background:#f5faff; vertical-align:top; color:#000;"|<br />
{|width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">This months featured article</h2><br />
|-<br />
|style="color:#000;"| <br />
<br />
{{Template:This_weeks_featured_article}} [[The Blue Book|'''More..''']]<br />
<br />
|-<br />
! <br />
|-<br />
|}<!----------------------------------Categories---------------------><br />
|class="MainPageBG" style="width:30%; border:1px solid #23297A; background:#f5faff; vertical-align:top"|<br />
{| width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
!<br />
<br />
<h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">Categories</h2><br />
|-<br />
|-<br />
|style="width:15em; vertical-align:right; font-weight:bold;"|<br />
[[Image:natural_bis.gif|natural.gif]] [[:Category:Coastal and marine natural environment|Natural environment]]<br><br><br />
[[Image:human_bis.gif|human4.gif]] [[:Category:Coastal and marine human activities|Human activities]]<br><br><br />
[[Image:impacts_bis.gif|impacts.gif]] [[:Category:Coastal and marine issues and impacts|Issues and impacts]]<br><br><br />
[[Image:earth_bis.gif|earth2.gif]] [[:Category:Coastal and marine areas and locations|Areas and locations]]<br><br><br />
[[Image:management-bis.gif|Management.gif]] [[:Category:Coastal management|Coastal management]]<br><br><br />
[[Image:people_bis.gif|people.gif]] [[:Category:People and organisations in coastal management|People and organisations ]] <br />
|}<br />
|}<br />
{{#categorytree:Coastal and marine system|mode=pages|onlyroot=on|style=border:1px solid gray; padding:0.7ex; vertical-align:right; background-color:#f5faff;}}<br />
<br><br />
'''Welcome to the Coastal Wiki, your guide to coastal knowledge and experience'''<br><br />
You may find information on any coastal topic by entering a corresponding term in the search window. “Go” will direct you to an article with this title (if such an article exists); “Search” will provide an overview of articles in which your search term appears. You will find an explanation of coastal terms and concepts in the [[Glossary]].<br />
<br />
We also invite coastal and marine practitioners, policymakers and scientists to make a contribution to this new concept in sharing European knowledge and experience in integrated coastal zone management. You may contribute in several ways: you may improve or update an existing article, you may add a discussion page to an existing article or you may add a new topic.<br />
<br><br><br />
<br />
'''How to contribute to the Coastal Wiki'''<br><br />
You have unrestricted access to the Coastal Wiki. But for adding or editing articles an authorisation is required. This is a major difference with the general wikipedia. For obtaining an editing authorisation you may contact your [http://www.encora.eu/networks.php national coordination office] or you may simply send an email to info@encora.eu. You will receive a request to provide contact information for the Wiki Contact Database. Anonymous contributions to the Coastal Wiki are precluded. Authors, co-authors and editors of articles are explicitly acknowledged. Your contribution will be reviewed by the coordinator of the theme where your article best fits. The theme coordinators also check that your contribution is [[links|adequately linked]] to existing articles on similar or related topics. <br />
<br />
You should remember that the Coastal Wiki is primarily meant for disseminating knowledge to a broader audience than the circles of specialists working at the frontiers of science. It is not meant for publishing original research; it is a vehicle for disseminating knowledge complementary to the traditional peer-reviewed scientific journals. Please read the [[Basic setup, rules and guidelines]] and [[How to edit an article]] before you start writing an article.<br />
<br><br><br />
<br><br />
<!------------------------------Bottom table---------------------><br />
{| style=" width:100%; border:1px solid #23297A; margin:0em 0em 1em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
<br />
|style="width:25%"| [[Help:Contents|'''Help pages''']] <br />
|style="width:25%"|[[glossary|'''Glossary''']] <br />
|style="width:25%"| [[Special:Popularpages|'''Popular pages''']] <br />
|style="width:25%" align="right"| [[Articles that need expanding|'''Articles that need expanding''']]<br />
<br />
|}<br />
<!------------------------------end of Bottom table---------------------></div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=WiSAR_-_Wind_retrieval_from_synthetic_aperture_radar&diff=32373
WiSAR - Wind retrieval from synthetic aperture radar
2009-08-04T09:27:29Z
<p>Wouter Kreiken: /* References */</p>
<hr />
<div>===Introduction===<br />
Today, several scatterometers (SCATs) are available that measure ocean surface wind fields with a resolution of up to 25 km on a global and operational basis. Originally they were not designed to observe also small-scale wind features, which are especially important in coastal areas. However, satellite-borne synthetic aperture radars (SARs) offer this unique opportunity, as they image the ocean surface with a much higher resolution than SCATs, typically below 100 m (Fig. 1). Several SARs have been launched in the last 12 years and are valuable tools for measuring geophysical parameters such as ocean surface winds, waves, and sea ice.<br />
[[Image:WiSAR1.jpg|thumb|left|'''Figure 1''': Wind fields of the Adriatic Sea resulting from scatterometer data a) resolution of 25 km and from SAR data b) resolution of 300 m. The small scale coastal wind jets, which are visible in the WiSAR retrieved wind field cannot be detected in the simulated scatterometer wind field.]]Most satellite borne SAR systems operate at the C-band at moderate incidence angles between 15° and 50°. For the electromagnetic wavelength of ~ 5 cm and of the incidence angles of 15-50°, the backscatter of the ocean surface is primarily caused by the small-scale ocean surface roughness with a horizontal scale of 5–10 cm. The small-scale surface roughness is strongly influenced by the local wind field, and therefore allows it to relate the radar backscatter to the wind parameters.<br />
[[Image:WiSAR2.jpg|thumb|right|'''Figure 2''': SAR image of the island Rügen, Germany, acquired by the European satellite ERS-1 on August 12th 1991.]]<br />
<br />
===SAR wind retrieval===<br />
The retrieval of ocean surface wind from SAR is a two-step process; in the first step, wind directions are retrieved, which are a necessary input in the second step. Wind directions are extracted from wind-induced streaks, which are aligned with wind direction and which are visible in the SAR image (Fig. 2). Orientations of these streaks are extracted by using the Local Gradient (LG) Method (Horstmann et al., 2002 <ref name="H">Horstmann, J., Koch, W., Lehner, S. & Tonboe, R. (2002). Ocean winds from RADARSAT-1 ScanSAR. Canadian Journal of Remote Sensing, 28 (3), 524-533.</ref>, Koch, 2004<ref name="K">Koch, W., (2004). Directional analysis of SAR images aiming at wind direction. IEEE Transactions on Geoscience & Remote Sensing, 42 (4), 702-710.</ref>). In the second step wind speeds are retrieved from the backscattered normalized radar cross section (NRCS) of the ocean surface by utilizing a geophysical model function (GMF). The GMF describes the dependence of the NRCS on the wind and radar imaging geometry (Horstmann and Koch, 2005<ref name="H1">Horstmann, J., & Koch, W. (2005). Comparison of SAR Wind Field Retrieval Algorithms to a Numerical Model utilizing ENVISAT ASAR Data. IEEE Journal of Oceanic Engineering, 30 (Iss.3), 508-515, doi 10.1109/JOE.2005.857514.</ref>).<br />
[[Image:WiSAR3.jpg|thumb|left|'''Figure 3''': SAR image acquired by the European satellite ERS-1 in the marginal ice zone off the coast of Spitzbergen. a) The mask that results from filtering and b) wind directions resulting from the LG method with (black arrows) and without (white arrows) consideration of the filter.]]For the retrieval of wind direction, the SAR image is smoothed and reduced to resolutions of 100, 200, and 400 m, so that three SAR images are generated. From each of these images, local directions are computed, which are defined by the normal to the LG, which have a 180 degree ambiguity in wind direction. In the next step, all pixels that are affected by non wind- induced features are masked and excluded from further analysis (Fig 3.). Therefore, high resolution land masks and SAR image filters are applied (Koch 2004<ref name="K"/>). From all of the resulting directions, only the most frequent directions in a predefined grid cell are selected. The 180 directional ambiguities are removed by considering weather prediction models.<br />
For wind-speed retrieval a GMF is applied. It relates the NRCS of the ocean surface to the local near-surface wind speed, wind direction and incidence angle. In case of the SARs, which operates at C-band with vertical polarization (VV), a well tested empirical GMF exists. For wind-speed retrieval from C-band, SAR images acquired with horizontal (HH) polarization, no similar well-developed models exist, so that the horizontal polarized NRCS is converted to the vertical polarized NRCS via the [[Image:WiSAR4.jpg|thumb|right|'''Figure 4''': WiSAR retrieved wind field of hurricane Ivan. The SAR data were acquired by the Canadian satellite Radarsat-1 on September 10th 2004 at 2307 UTC. The eye of hurricane Ivan is situated about 80 km south of Kingston, Jamaica.]]polarization ratio (PR). So far, the PR is not well known and several different PRs have been suggested in literature. However, it has been shown that an incidence dependent PR shows sufficient good results for SAR wind speed retrieval (Horstmann et al., 2000<ref name="H2">Horstmann J., Koch, W., Lehner, S. & Tonboe R. (2000). Wind Retrieval over the Ocean using Synthetic Aperture Radar with C-band HH Polarization. IEEE Transactions on Geoscience & Remote Sensing, 38 (5), 2122-2131.</ref>).<br />
<br />
===Validation===<br />
Several comparisons of SAR retrieved wind fields with results from numerical weather prediction models at wind speeds below 25 ms<sup>-1</sup> have shown that WiSAR is capable of retrieving winds with a typical error of ~20° in wind direction and ~2 ms<sup>-1</sup> in wind speed (Horstmann et al., 2003<ref name="H3">Horstmann J., Schiller, H., Schulz-Stellenfleth, J. & Lehner, S. (2003). Global Wind Speed Retrieval from SAR. IEEE Transactions on Geoscience & Remote Sensing, 41 (10), 2277-2286.</ref>; Horstmann and Koch, 2005<ref name="H1"/>; Koch and Feser, 2006<ref name="K1">Koch, W. and F. Feser, (2006). Relationship between SAR-derived wind vectors and wind at 10-m height represented by a mesoscale model. Monthly Weather Review, 134, 1505-1517.<br />
</ref>). It has also been shown that it is possible to retrieve wind fields under extreme high wind situations (Horstmann et al. 2005<ref name="H4">Horstmann, J., Thompson, D.R., Monaldo, F., Graber, H.C. & Iris, S. (2005). Can Synthetic Aperture Radars be used to Estimate Hurricane Force Winds?. Geophysical Research Letters, 32, L22801. doi: 10.1029/2005GL023992. <br />
</ref>). Fig. 4 shows an example of a WiSAR retrieved wind field of hurricane Ivan (10. September 2004). However, recent studies of SAR retrieved wind fields from tropical cyclones have shown that the error in wind speed is significantly larger at wind speeds above 25 ms<sup>-1</sup>.<br />
<br />
==References==<br />
<references/><br />
<br/><br />
{{author <br />
|AuthorID=16905<br />
|AuthorFullName= Horstman, Jochen<br />
|AuthorName=Username}}<br />
<br />
{{author <br />
|AuthorID=16897<br />
|AuthorFullName= Koch, Wolfgang<br />
|AuthorName=Username}}<br />
<br />
[[Category:Remote Sensing in Coastal and Marine Research]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Detecting_the_unknown_-_novelty_detection_of_exceptional_water_reflectance_spectra&diff=32372
Detecting the unknown - novelty detection of exceptional water reflectance spectra
2009-08-04T09:25:45Z
<p>Wouter Kreiken: /* References */</p>
<hr />
<div>===Introduction===<br />
Synoptic monitoring of large areas in coastal waters can be performed by remote sensing using multispectral sensors on-board satellites. Many methods are in use which enable the detection and quantification of ‘standard algae’ or specific algae blooms using their known spectral response. The ‘novelty detection’ aims to find spectra outside the known range which are referred to as exceptional spectra.<br />
<br />
[[Image:Detecting_unknown_donno1.jpg|center]]<br />
<br />
This order given to the hero of a Russian fairy tale could be used to summarise the request received to detect exceptional water reflectance spectra.<br />
A recent review of the novelty detection techniques available is presented by (Markou and Singh, 2003)<ref name="M">Markou, M., & Singh, S. (2003). Novelty detection: A review – Part 1: Statistical approaches. Signal Processing, 83 (12), 2481–2497</ref>.<br />
[[Image:Detecting_unknown_1.jpg|thumb|left|'''Figure 1''': Examples of water reflectance spectra measured by MERIS.]]The present study aimed to develop a novelty detection scheme for water reflectance data which could be used operationally. The basic idea behind this approach is to use a large number of reflectance spectra from one complete year for a defined region, here the North Sea, so as to include the annual cycle of plankton species (including their blooms etc.) to teach a learning system ‘what is normal.’ Only distinctive deviations from these known spectra should be classified as novel. Thus, the algorithm should accept all reflectance spectra from the training period as being normal but should still be sensitive enough to detect novel situations. <br />
<br />
[[Image:Detecting_unknown_2.jpg|thumb|right|'''Figure 2''': The figures show a subset of a 2 dimensional dataset together with isolines of the measure ρ(x) which enclose 95% of the data for the four different approaches.<br />
a) refers to the statistical model, <br />
b) to the auto-associative Neural Net,<br />
c) to the Neural Net classifier and <br />
d) to the tessellation.]]<br />
===The Algorithm===<br />
The selection of the appropriate algorithm is one central issue of novelty detection. It is intimately connected with the type and structure of the data to be tackled. The water reflectances are measured at nine different wavelengths, all of which will be used in the present algorithms. Bio-optical models often exclude several wavebands or give other wavelengths more weight. Examples of water reflectance spectra are shown in Fig. 1.<br />
Since our aim is to detect novel situations with unknown spectral signature we use all the information available. However, due to the resulting high dimensionality of the data set, nine dimensions of a point correspond to the nine wavelengths, the performance of different algorithms was carefully analysed. Different approaches of novelty detection, namely: a) a simple statistical scheme, b) an auto-associative Neural Net, c) a Neural Net classifier, and d) a tessellation scheme were analysed. Fig. 2 shows the enclosement of the different methods for a 2-dimensional case. The tessellation showed to be the optimal novelty detection scheme.<br />
<br />
[[Image:Detecting_unknown_3.jpg|thumb|left|'''Figure 3''': Flowchart of the tessellation scheme.]]<br />
===Scheme===<br />
The tessellation starts by choosing a radius R in the 9-dimensional space (dimensions for 9 wavelengths). <br />
<br />
::*The first point (spectrum) becomes the first centre. <br />
::*For each of the remaining points the smallest of the distances to all centres is compared with R. If the distance is larger than R the point is included in the set of centres. <br />
::*In the second step each point is assigned to that centre to which it is closest (Voronoi tessellation).<br />
<br />
For each of the patches obtained by the tessellation the mean (centre of gravity) and the covariance matrix is calculated and finally for a given point (spectrum) the minimal Mahalanobis distance to all centres of the tessellation is determined. <br />
This minimal Mahalanobis distance to all centres of the tessellation is the main parameter to find new, unknown points i.e. spectra. A flowchart of the tessellation scheme is shown in Fig. 3.<br />
To minimize 'false alarms' and to optimise the discrimination power two additional conditions have to be fulfilled. The pixel must have a minimal distance to clouds of 3 pixels and only pixels within larger patches are considered.<br />
<br />
[[Image:Detecting_unknown_4.jpg|thumb|right|'''Figure 4''': North Sea novelty training region.]]<br />
===North Sea MERIS Data===<br />
As an application for the tessellation novelty detection scheme we used MERIS data of the North Sea. The logarithms of the remote sensing reflectances in the first nine MERIS channels (centred at wavelengths λ = 413, 443, 490, 510, 560, 620, 665, 681, 708 nm) were used to span the space. <br />
For the dataset defining the ‘normal’ situation we used all MERIS scenes from June 26th 2003 to June 29th 2004 from a region of the North Sea (Fig. 4). We excluded pixels from the sun glint part as well as those which had one or more negative reflectances (bad atmospheric correction). Then ~ 1,000 pixels from each scene were randomly sampled thus ending up with 115,331 pixels for the ‘training’.<br />
We decided to declare points as representing novelty if their distance to the tessellation was above 7.5. The distance cut-off of 7.5 left only 38 pixels remaining from the training points. However, if we applied the cut to the 288 complete scenes, with 16,575,000 pixels of the time range from which the training data set was selected, we found 110,718 pixels. After applying a cloud distance cut (3 pixels) and a minimal patch size cut (19 out of 5 x 5) we reduced this number to 2,670 in 26 scenes.<br />
To remove remaining 'false alarms' in the training period we identified four groups of spectra for which we calculated the centre of gravity and the covariance matrix and appended them to the existing tessellation information. After this addition only one false alarm remained in the training set.<br />
<br />
[[Image:Detecting_unknown_5.jpg|thumb|left|'''Figure 5''': Location of the novelty found on July 30th 2004, August 3rd 2004 and August 5th 2004 indicated in blue.]]<br />
===Finding Novelties===<br />
The test application data set comprised 223 scenes from June 30th 2004 to October 13th 2005. 10 scenes were initially marked as novelty. <br />
In the scene from November 19th 2004 novelty was signaled in the Skagerrak area, however, after further inspection this was shown to be simply a processing failure in that a significant number of water reflectances were just unity. <br />
Several scenes show 'novelties' (June 19th, 23rd, 26th, 28th and July 2nd, 18th 2005) and are located in the central and northwestern North Sea. These findings look like distinctive blooms of coccolithophores, which are in general quite frequent every year, but these spectra were classified as novelties due to their more pronounced blue reflectance as compared to those events within the training period.[[Image:Detecting_unknown_6.jpg|thumb|right|'''Figure 6''': North Sea MERIS scene from August 3rd 2004. The water-colour enhanced picture shows a reddish colour in the German Bight were the novelty was detected (Fig. 4).]] <br />
For further practical novelty detection, and for those not immediately interested in coccolithophore bloom alarms, one would append these spectra to the tessellation as outlined in the previous paragraph.<br />
Beside one false alarm three scenes with signaled novelties show a red tide near the island Helgoland on July 30th and on August 3rd and 5th 2004 (Fig. 5). This red tide was visible from satellite image (Fig. 6) and also at sea (Fig. 7) where observed during a measuring campaign between Cuxhaven and Helgoland on August 3rd 2004 and identified as Myrionecta rubra. Standard algorithms also detected an increase in the chlorophyll content. <br />
<br />
[[Image:Detecting_unknown_7.jpg|thumb|left|'''Figure 7''': German Bight water on August 3rd 2004 with an obvious reddish colour stemming from a significant bloom of Myrionecta rubra.]]<br />
===Conclusion & Outlook===<br />
A novelty detection scheme which is suitable for regular monitoring purposes using multispectral remote sensing data has been constructed. It was applied to MERIS water reflectances and has a low failure (false positive) rate. It was successful in finding exceptional algae blooms, one of which was also identified as a red tide by in situ measurements.<br />
To reach this low failure rate it was necessary to use not only the spectral information but also to avoid pixels close to clouds and to require a minimum novelty patch size.<br />
The novelty detection scheme developed is flexible and adaptable to various monitoring needs. It is currently operating as standard service within InterRisk, an FP6-IST project addressing interoperable GMES services for environmental risk management in marine and coastal areas of Europe.<br />
<br />
==References==<br />
<references/><br />
<br/><br />
{{author <br />
|AuthorID=16888<br />
|AuthorFullName= Schiller, Helmut<br />
|AuthorName=Username}}<br />
<br />
{{author <br />
|AuthorID=16887<br />
|AuthorFullName= Schönfeld, Wolfgang<br />
|AuthorName=Username}}<br />
<br />
{{author <br />
|AuthorID=16895<br />
|AuthorFullName= Krasemann, Hansjörg<br />
|AuthorName=Username}}<br />
<br />
[[Category:North Sea]]<br />
[[Category:Remote Sensing in Coastal and Marine Research]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Main_Page&diff=32325
Main Page
2009-08-03T09:31:16Z
<p>Wouter Kreiken: The_Blue_Book</p>
<hr />
<div><!----------------------------Introduction-----------------><br />
{| style="width:100%; border:2px solid #23297A; margin:0em 0em 1em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
|align="top"|<br />
<div style="font-size:100%; padding-bottom:0.15em;">Welcome to the [[Coastal Wiki|Coastal and Marine Wiki]], an Internet encyclopaedia of [[Special:Statistics|{{NUMBEROFARTICLES}}]] information pages for and by coastal professionals providing up-to-date high quality Coastal and Marine information. [[Coastal Wiki:Why, What and for Whom?|More about the Coastal and Marine Wiki]]</div><br />
|}<br />
<!----------------------End of introduction-----------------><br />
<br />
<!-----------------------Today's featured article, Did you know--------------------><br />
{|style="border-spacing:8px; margin:0px -8px;"<br />
|class="MainPageBG" style="width:70%; border:1px solid #23297A; background:#f5faff; vertical-align:top; color:#000;"|<br />
{|width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">This months featured article</h2><br />
|-<br />
|style="color:#000;"| <br />
<br />
{{Template:This_weeks_featured_article}} [[The Blue Book|'''More..''']]<br />
<br />
|-<br />
! <br />
|-<br />
|}<!----------------------------------Categories---------------------><br />
|class="MainPageBG" style="width:30%; border:1px solid #23297A; background:#f5faff; vertical-align:top"|<br />
{| width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
!<br />
<br />
<h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">Categories</h2><br />
|-<br />
|-<br />
|style="width:15em; vertical-align:right; font-weight:bold;"|<br />
[[Image:natural_bis.gif|natural.gif]] [[:Category:Coastal and marine natural environment|Natural environment]]<br><br><br />
[[Image:human_bis.gif|human4.gif]] [[:Category:Coastal and marine human activities|Human activities]]<br><br><br />
[[Image:impacts_bis.gif|impacts.gif]] [[:Category:Coastal and marine issues and impacts|Issues and impacts]]<br><br><br />
[[Image:earth_bis.gif|earth2.gif]] [[:Category:Coastal and marine areas and locations|Areas and locations]]<br><br><br />
[[Image:management-bis.gif|Management.gif]] [[:Category:Coastal management|Coastal management]]<br><br><br />
[[Image:people_bis.gif|people.gif]] [[:Category:People and organisations in coastal management|People and organisations ]] <br />
|}<br />
|}<br />
{{#categorytree:Coastal and marine system|mode=pages|onlyroot=on|style=border:1px solid gray; padding:0.7ex; vertical-align:right; background-color:#f5faff;}}<br />
<br><br />
'''Welcome to the Coastal Wiki, your guide to coastal knowledge and experience'''<br><br />
You may find information on any coastal topic by entering a corresponding term in the search window. “Go” will direct you to an article with this title (if such an article exists); “Search” will provide an overview of articles in which your search term appears. You will find an explanation of coastal terms and concepts in the [[Glossary]].<br />
<br />
We also invite coastal and marine practitioners, policymakers and scientists to make a contribution to this new concept in sharing European knowledge and experience in integrated coastal zone management. You may contribute in several ways: you may improve or update an existing article, you may add a discussion page to an existing article or you may add a new topic.<br />
<br><br><br />
<br />
'''How to contribute to the Coastal Wiki'''<br><br />
You have unrestricted access to the Coastal Wiki. But for adding or editing articles an authorisation is required. This is a major difference with the general wikipedia. For obtaining an editing authorisation you may contact your [http://www.encora.eu/networks.php national coordination office] or you may simply send an email to info@encora.eu. You will receive a request to provide contact information for the Wiki Contact Database. Anonymous contributions to the Coastal Wiki are precluded. Authors, co-authors and editors of articles are explicitly acknowledged. Your contribution will be reviewed by the coordinator of the theme where your article best fits. The theme coordinators also check that your contribution is [[links|adequately linked]] to existing articles on similar or related topics. <br />
<br />
You should remember that the Coastal Wiki is primarily meant for disseminating knowledge to a broader audience than the circles of specialists working at the frontiers of science. It is not meant for publishing original research; it is a vehicle for disseminating knowledge complementary to the traditional peer-reviewed scientific journals. Please read the [[Basic setup, rules and guidelines]] and [[How to edit an article]] before you start writing an article.<br />
<br><br><br />
<br><br />
<!------------------------------Bottom table---------------------><br />
{| style=" width:100%; border:1px solid #23297A; margin:0em 0em 1em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
<br />
|style="width:25%"| [[Help:Contents|'''Help pages''']] <br />
|style="width:25%"|[[glossary|'''Glossary''']] <br />
|style="width:25%"| [[Special:Popularpages|'''Popular pages''']] <br />
|style="width:25%" align="right"| [[Articles that need expanding|'''Articles that need expanding''']]<br />
<br />
|}<br />
<!------------------------------end of Bottom table---------------------></div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Template:This_weeks_featured_article&diff=32324
Template:This weeks featured article
2009-08-03T09:30:27Z
<p>Wouter Kreiken: /* The blue book */</p>
<hr />
<div>==The Blue Book==<br />
<br />
[[Image:Diver_right.jpg|100px|right|thumb|Logo of the Blue Book]]<br />
<br />
An Integrated Maritime Policy for the European Union -The '''Blue Book'''<ref>COM(2007)575 final, Brussels, 10.10.2007 -An Integrated Maritime Policy for the European Union -Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions<br />
</ref><br />
<br />
The European Commission launched a comprehensive consultation and analysis of how Europe relates to the sea. <br />
''(See also the [[Green Paper for a EU Maritime Policy|Green Paper for an EU Maritime Policy]])''<br />
<br />
Building in this valuable input the Commission presented, on 10 October 2007, its vision for '''an Integrated Maritime Policy for the European Union''', also called the '''Blue Book'''. This vision is based on the clear recognition that all matters relating to Europe's oceans and seas are interlinked, and that sea-related policies must develop in a joined-up way if are to reap the desired results<br />
<br />
The Blue Book is accompanied by the other 3 documents:<br />
<br />
*a [http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=COM:2007:0574:FIN:EN:PDF Report on the stakeholder consultation results]<br />
*a detailed [http://ec.europa.eu/maritimeaffairs/pdf/ActionPaper/action_plan_en.pdf Action Plan]-aiming at exploring the full potential of sea-based economic activity in an environmental sustainable manner<br />
*an [http://ec.europa.eu/maritimeaffairs/pdf/summary/sec_2007_1280_en.pdf Impact Assessment]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Salt_marshes&diff=30655
Salt marshes
2009-07-09T13:45:34Z
<p>Wouter Kreiken: featured</p>
<hr />
<div>{{featured}}<br />
<br />
This article describes the habitat of the salt marshes. It is one of the sub-categories within the section dealing with biodiversity of [[marine habitats and ecosystems]]. It gives an overview about the characteristics, distribution, evolution, [[zonation]], succession, biota, threats, functioning and adaptations of the organisms that live in salt marshes. <br />
<br />
In 2008 the European Union commissioned a series of Habitat Management Models for several of the more important communities. Included in this was a model for 1330 Atlantic salt meadows (Glauco-Puccinellietalia maritimae).<br />
<br />
Visit the European Union web site at [http://ec.europa.eu/environment/nature/natura2000/management/habitats/models_en.htm] to download a copy of the Habitat Management Model for the above community.<br />
<br />
<br />
==Introduction==<br />
<br />
Salt marshes are defined as natural or semi-natural terrestrial '''halophytic''' ecosystems. They largely occur in the [[intertidal]] zone between land and the sea and are covered by salty or brackish water for at least some of the time. They replace [[mangrove]]s in temperate and arctic regions. The dominant flora is composed of [[Halophytic plants|halophytic plant]] such as '''grasses''', '''shrubs''' and '''herbs'''. The flora is rather species poor. The sediment consists of [[mud]] and sand. The salt marshes are normally associated with [[mud]] flats but also occur on sand flats. These [[Tidal flats from space|mud flats]] are sometimes dominated by [[algae]]. They are regularly subjected to tidal movement, the height of which can vary from a few centimetres (in enclosed seas such as the Baltic Sea) to several metres in open sea areas such as the Atlantic. The drainage of this seawater is controlled by a meandering network of '''tidal channels'''. Through these channels sediments, [[detritus]], dissolved [[nutrient]]s, [[plankton]] and small fishes are flushed in and out the salt marshes. <br />
<br />
<br />
[[image:Saefringhe NIOO-CEME.jpg|center|thumb|300px|caption|Land of Saeftinghe - Belgium <ref>http://www.marbef.org</ref>]]<br />
<br />
==Distribution==<br />
<br />
Salt marshes are widely distributed in [[Estuaries and tidal rivers|estuarine]] systems around the world. They also occur in [[deltas]], [[rias]] and on open coasts. Although sediment is a prerequisite for their growth in height and width, salt marsh communities can occur in areas with limited or no sediment supply. Examples include sea water drenched cliffs and slopes on exposed coasts, at the head of sea lochs and rocky beaches (Doody 2008) <ref> Doody, J.P. (2008) ''Saltmarsh Conservation, Management and Restoration''. Coastal Systems and Continental Margins, Volume 12, Springer, 217 pp. </ref> They have a range from the Arctic region over Europe, Africa, America, Asia to the coast of Australia.<br />
<br />
The most extensive development of these salt marshes occurs in estuaries with a large tidal range, abundant fine-grained sediments, sheltered location where particles can settle out of the water column and moderate climate. <br />
<br />
<br />
[[image:Distribution salt marshes.gif|center|thumb|500px|caption|Distribution of salt marshes (green), wetlands (orange and yellow) and mangroves (pink) <ref>http://cache.eb.com/eb/image?id=6576&rendTypeId=4</ref>]]<br />
<br />
==Evolution==<br />
<br />
Salt marshes evolve over time from young marshes to old marshes. The natural '''young marshes''' in eastern USA consist for the largest part of low marsh cordgrass ''Spartina alterniflora''. [[Nutrient]]s are transported by [[Tide|tidal]] flooding through the [[Tide|tidal]] channels. This makes it possible for the grasses to grow thickly and abundantly what weakens the effect of waves and tidal [[currents]] so the depositional rate of [[mud]] increases. [[Erosion]] is reduced by the roots and rhizomes of the plants. At the time that the marsh surface builds up above the high water level, the high marsh plants invade, outcompete and replace the low marsh plants. When the quantity of the low and high marshes is equal, the ecosystem is in a mature stage of development. The continued deposition of [[mud]] converts most of the low marshes into high marshes. These are called the '''old marshes'''. Little water flows through the tidal channels and the marshes are elevated. At this time, streams and rivers deposit sand and [[mud]] on these high marshes and convert it into a dry land that is disconnected from ocean influences. <ref>Pinet P.R. 1998.Invitation to Oceanography. Jones and Barlett Publishers. p. 508</ref><br />
<br />
==Requirements for development==<br />
<br />
The requirements for development of salt marshes are:<br />
<br />
* They need '''fine-grained sediments'''. <br />
* There may be '''no strong waves or tidal currents'''. <br />
* They need salty conditions to grow. They are '''halotolerant''' and have adaptations to these conditions. <br />
* They need a temperate or cool '''temperature'''. Freezing temperatures can occur, but are not damaging the plants.<br />
* They need a '''wide tidal range'''. This is important because it limits the [[erosion]], makes deposition of sediments possible and causes a well-marked [[zonation]].<br />
<br />
<br />
==Zonation==<br />
<br />
Based on the topography and characteristic plant assemblages, salt marshes are classified as low, medium and high marshes and is related to the number of tidal submergences per year (Adam 1990)<ref>Adam, P., 1990. ''Saltmarsh Ecology''. Cambridge University Press, Cambridge</ref>. Below the '''low marshes''' are the [[Tide|tidal]] creeks. These creeks are channels that are flushed with salty or brackish water. The low marshes extend from the mean low water neap [[tide]] to the mean high water spring [[tide]]. An example from the eastern shores of the United States of America is dominated by the smooth cordgrass ''Spartina alterniflora''. This grass spreads rapidly. <br />
The '''high marshes''' extend from the high water tide to the highest spring [[tide]]. It is only flooded during extremely high tides and during storms. It resembles more to terrestrial than to a true marine environment. The plant community is more diverse than the low marshes. It consists of ''Spartina patens'', the saltwort grass ''Salicornia'' species and the spike grass ''Distichlis spicata''. Distribution, density and activity of invertebrates are mainly controlled by protection, food and frequency of tidal flooding. <ref>Pinet P.R. 1998.Invitation to Oceanography. Jones and Barlett Publishers. p. 508</ref><br />
<br />
<br />
[[image:Zonation salt marshes.jpg|center|thumb|400px|caption|Zonation of salt marshes <ref>http://geology.usgs.gov/connections/fws/landscapes/blackwater_model.htm</ref>]]<br />
<br />
==Succession==<br />
<br />
Succession is the serial development of different vegetation types at one place in time. It is a complex process and the factors determining zonation and succession in salt marshes are discussed in some detail in Adam (1990) pages 49-57, Gray (1992) <ref>Gray, A.J., 1992. Saltmarsh plant ecology. In: ''Saltmarshes: morphodynamics, conservation and engineering significance'', J.R.L., Allen, & K., Pye, eds., 63-79. Cambridge University Press, Cambridge.</ref> and Packham & Willis (1997) pages 107-114 <ref>Packham, J.R. & Willis, A.J., 1997. ''Ecology of dunes, saltmarsh and shingle''. Chapman & Hall, London.</ref>. <br />
<br />
The succession starts with unicellular algae such as diatoms sticking the sand together by production of mucus. This causes a brownish biofilm on the substrate. <br />
<br />
After this stage, filamentous [[algae]] optimize the fixation of sediments. These [[algae]] are mostly blue-green algae, Cyanophyta and Chlorophyta. Small gastropods can feed and develop in huge quantities on it. Locally, the filamentous alga ''Vaucheria'' can form banquettes or elevations. Brown algae are loosely associated with this stage. <br />
<br />
A next stage is the germination of species such as ''Salicornia''. The seeds germinate after some desalination of the soil by rain. Between and around the glassworts takes extra sediment accumulation place. This results in elevating the substrate and makes it more stable. Other species such as ''Spartina maritima'' and ''Spartina anglica'' compete for the same place. ''S. maritima'' is an indigenous species of continental Europe and ''S. anglica'' is imported from the British Islands. Note the hybridisation and invasion of [[Spartina - an introduction|"Spartina" spp]] is a worldwide phenomenon see chapter 9 (Doody 2008). <br />
<br />
In Europe, other plants can occur. These herbs are Common Saltmarsh-grass (''Puccinellia maritima''), Sea Plantain (''Plantago maritima''), Sea Arrow-grass (''Triglochin maritinum''), Sea Aster (''Aster tripolium''), English Scurvy-grass (''Cochlearia anglica''), Common Sea-lavender (''Limonium vulgare''), Sea Purslane (''Halimione portulacoides''), the red alga ''Bostrychia scorpioides'' and ''Catenella caespitosa''. <ref>Eric Coppejans – Course Biodiversity of aquatic food webs: from algae to marine mammals UGent</ref>. ''Juncus maritimus'' is another species that can occur in salt marshes. <br />
<br />
<br />
<gallery><br />
Image:Biofilm.jpg|Biofilm of unicellular algae <ref name="multiple">Eric Coppejans - http://www.vliz.be/imis/imis.php?module=person&persid=134</ref><br />
Image:Filamentous algae.JPG|Fixation of the sediment by blue-green and green algae <ref name="multiple">Eric Coppejans - http://www.vliz.be/imis/imis.php?module=person&persid=134</ref> <br />
Image:Salicornia.JPG|''Salicornia perennis'' <ref name="multiple">Eric Coppejans - http://www.vliz.be/imis/imis.php?module=person&persid=134</ref><br />
Image:Spartina.JPG|''Spartina townsendii '' <ref name="multiple">Eric Coppejans - http://www.vliz.be/imis/imis.php?module=person&persid=134</ref><br />
Image:Trigochlin.JPG|''Triglochin maritinum '' <ref name="multiple">Eric Coppejans - http://www.vliz.be/imis/imis.php?module=person&persid=134</ref><br />
Image:Aster.JPG|''Aster tripolium '' <ref name="multiple">Eric Coppejans - http://www.vliz.be/imis/imis.php?module=person&persid=134</ref><br />
Image:Limonium vulgare.JPG|''Limonium vulgare '' <ref name="multiple">Eric Coppejans - http://www.vliz.be/imis/imis.php?module=person&persid=134</ref><br />
</gallery><br />
<br />
==Functioning and adaptations==<br />
<br />
Salt marshes have several functions and adaptations to a life in an intertidal ecosystem. They need to conquer some problems to be resistant to the environment. Therefore, it is important to have some adaptations to survive.<br />
The first problem is that the plants are freshwater plants. This causes '''waterstress'''. For this reason, they have to take up water against the osmotic pressure. To overcome the negative osmotic pressure, they generate a negative hydrostatic pressure (by transpiration processes). They have thin, fleshy leaves and are sensitive to extra stress such as pollution. Anatomically, the plants are adapted through strong '''lignification''', a well-developed '''epidermis''' and '''succulent leaves and stems'''. Evaporation can be limited by thin leaves with scale-like '''hairs'''. <br />
Physiologically, plants are adapted by accumulating salt in their tissues. In this way, normal [[osmosis]] is possible. Other plants have '''salt gland''' cells on the lower surface of the leaves and excrete the salt from its tissue. <br />
A second problem is the '''anoxic environment'''. The underground in which they root is saturated with water. The tissue of the plants requires oxygen for [[respiration]]. Gas diffusion between gas particles can only supply this need in soils that are not waterlogged. Even when the water is saturated with oxygen, its concentration is too low and the diffusion in water is very slow. This is solved by '''aerenchyma''', a tissue that can provide air to the submerged parts of the plants. Roots are superficial systems because of the anoxic sediments. These systems are composed of perennial thick roots with a corky layer and without root hairs. To fixate the substrate, shortliving thin and strongly branched roots with numerous root hairs are developed so they can take up nutrients. <br />
Salt marshes have a whole range of functions. It plays an important role as a '''sediment trap'''. In this way, it regulates the water quality and helps '''stabilizing''' the coastlines. Salt marshes function as '''filtering systems''' and retain sediments, excess nutrients, toxic chemicals and disease-causing organisms. They remove nitrates and phosphates from rivers and streams which receive waste water effluents. Another function is the recharge and discharge of groundwater attributing to the '''water supply'''. <br />
Salt marshes function also as important [[habitat]], '''nursery''' grounds for larvae and small organisms, '''shelter''', providing '''food''' and a '''nesting''' ground for wading birds and other organisms. <ref>http://wwwutmsi.zo.utexas.edu/staff/dunton/EcoDynamics/MEDLec10.pdf</ref><br />
<br />
<br />
==Fauna==<br />
<br />
Small mammals, small fishes, birds, insects, spiders, and marine invertebrates are found in salt marshes. Marine '''invertebrates''' include amphipods, isopods, anemones, shrimps, crabs, , turtles, mollusks and gastropods. '''Fishes''' such as sticklebacks, silversides, eels and flounders are found in the waters of the salt marshes. The salt marshes are important breeding, feeding and overwintering grounds for '''waterfowl'''. These waterfowls consist of ducks, herons, Sharptailed Sparrows, Eurasian Oystercatchers, Reed Bunting,…<br />
The '''[[benthic]]''' community consists of mollusks, polychaeta and oligochaeta.<br />
The coastal freshwater marshes are species poor. The organisms that you can find here are water boatmen, flies, mosquitos and snails. Further there are mollusks, ducks, geese, muskrats, raccoons, minks and other small mammals. For some species, a seasonal appearance can be seen. <br />
In Saudi Arabia, salt marshes are grazing places for wild dromedaries. <ref>http://museum.gov.ns.ca/mnh/nature/nhns/h2/h2-5.htm</ref><br />
<br />
<br />
<gallery><br />
Image:Haematopus ostralegus M. Decleer.jpg|Eurasian oystercatcher <ref>http://www.marbef.com - Decleer M.</ref><br />
Image:water boatman E.S.Ross.jpg|Water boatman <ref>Ross E.S.</ref><br />
Image:Mink.jpg|European mink <ref>http://en.wikipedia.org/wiki/Mink</ref><br />
</gallery><br />
<br />
<br />
==Threats==<br />
<br />
The total number and area of salt marshes has been declining for many years. The main cause is enclosure, which removes the habitat from tidal inundation. This normally occurs in areas where the level is high enough and the area big enough for embankment to take place. This is usually achieved by the erection of a tidal barrier, sea wall or other structure designed to keep the sea out. This destroys the salt marsh as other uses, notably conversion to intensive agriculture, takes place. <br />
<br />
In south east England a special type of enclosed saltmarsh develops its own value as a semi-natural habitat. Once enclosed the saltmarsh is left 'unimproved' with creeks, and other features retained with little interference. Grazing or cropping for hay are often the only uses and with traditional management it develops into a wildlife habitat of some significance. The term [[Coastal grazing marsh]] is used to describe this habitat. <br />
<br />
Infilling for ports and harbours and other infrastructure completely destroys the habitat and with it any opportunities for restoration. Some areas outside the reclaimed zones can produce new marshes where relative sea level is falling or there is an abundant supply of new sediment and conditions suitable for growth of new plants. <ref>Council of Europe – Dijkema K.S. et al. 1984. Salt marshes in Europe. Nature and environment series No.30 p. 178</ref> With climate change and associated sea level rise this is becoming much less prevalent and the process of '[[coastal squeeze]]' occurs in many areas, especially around the margins of the southern North Sea <ref> Doody, J.P. (2004) 'Coastal squeeze' - an historical perspective. ''Journal of Coastal Conservation'', '''10/1-2''', 129-138.</ref>.<br />
<br />
'''Other threats''' include:<br />
<br />
* Over-grazing<br />
* Embankment<br />
* Excessive agricultural use<br />
* Urbanization<br />
* Recreation<br />
* [[Coast erosion|Coastal erosion]]<br />
* Pollution and industrial waste water <br />
* Invasion of ''Spartina anglica'' and ''Erytrigia'' (in eutrophic salt marshes)<br />
<br />
=Salt marsh restoration guide=<br />
<br />
For information of the management and restoration of saltmarshes in the UK see the Living with the Sea LIFE project, Coastal Habitat Restoration Guide - [http://www.english-nature.org.uk/livingwiththesea/project_details/good_practice_guide/habitatcrr/ENRestore/Habitats/Saltmarsh/Index.htm]<br />
<br />
==Case-study: Land van Saeftinghe==<br />
<br />
The [[Tide|tidal]] area ‘Drowned land of Saeftinghe’ (Verdronken land van Saeftinghe) is located at the eastern boundary between the Netherlands and Belgium, a few kilometers downstream Antwerp in the estuary of the Scheldt. It is an official nature reserve since 1976. Because of this legal protection, permits are obligatory for every intervention and strict entrance restrictions are applied.<br />
The land is a crosspoint where the river the Scheldt meets the salty water of the North Sea in the [[Estuaries and tidal rivers|estuary]] known as the Western Scheldt. In the past, the land was a very fertile polder. The area has a surface of 3,484 hectares. Almost 70 % of the area is overgrown by specific plants of the salt marsh. The residual 30 % consists of [[Tidal flats from space|mud flats]], sandbanks and a network of channels. Each [[tide]], the brackish water overflows a large part of the area. The plants there are totally adapted to this and are very unique. For huge quantities of birds, this area is an ideal breeding, rest and wintering place. This makes the area of international importance. Since 1996 it is a special protected area for birds (1979 Directive 79/409/EEC on the conservation of wild birds). <br />
<br />
<br />
[[image:gebiedbes-afb-1.gif|center|thumb|350px|caption|Area description of the Western Scheldt, with the Land of Saeftinghe in green <ref>http://www.hetzeeuwselandschap.nl/saeftinghe/algemeen/index.php</ref>]]<br />
<br />
<br />
In the past, a few dikes were created to promote the silting up. The northern dike connects a few stands with the dike. These dikes are still recognizable and are used as wandering path. The stands were used as hills where shepherds retreated when the [[tide]] became too high. <br />
The flora exists of approximately 50 wild plant species. [[Algae]] are not abundant in Saeftinghe because there is too little light that penetrates in the water. Organic matter and a lot of silt make the water turbid. Higher plants are more important in this area. One of the most common plants is pickle weed (''Salicornia''). But other salt marsh plants such as English Scurvy-grass (''Cochlearia anglica'') and Common Sea-lavender (''Limonium vulgare''). <ref>http://www.hetzeeuwselandschap.nl/saeftinghe/index.php</ref><br />
<br />
<br />
==References==<br />
<references/><br />
<br />
<br />
{{author<br />
|AuthorID=16323<br />
|AuthorFullName=TÖPKE, Katrien<br />
|AuthorName=Ktopke}}<br />
<br />
[[Category:Marine habitats and ecosystems]]<br />
[[Category:Typology of coastal and marine areas]]<br />
[[Category:Location of coastal and marine areas]]<br />
[[Category:Theme 7]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Salinization_adaptation_and_freshwater_supply_for_agriculture_in_the_Dutch_Delta&diff=30654
Salinization adaptation and freshwater supply for agriculture in the Dutch Delta
2009-07-09T13:44:34Z
<p>Wouter Kreiken: </p>
<hr />
<div>{{featured}}<br />
<br />
This article describes a case study, which provides an example of [[Problem structuring in decision-making processes|structuring problems]] in order to improve [[Stakeholder analysis|stakeholder dialogue]]. It uses the Delta area of the Netherlands and in particular focuses on issues surrounding the restoration of estuarine dynamics and [[sustainable]] supply of freshwater for agriculture.<br />
<br />
==Introduction==<br />
<br />
The delta of the rivers Rhine, Meuse and Scheldt, located in the Southwest of the Netherlands, is unique for its large water systems surrounded by [[dikes]] and [[dams]] to protect the hinterland against flooding. With the construction of a [[storm surge]] barrier in the Eastern Scheldt in 1986, the Dutch Delta Works safety restoration programs were completed. The construction of the Delta Works made the Southwest of the Netherlands safer, more accessible and several newly created freshwater basins provided opportunities for drinking water supply and agriculture. The hydraulic engineering projects have been executed allowing ecological concerns to be taken into account to the best available knowledge. As a result the economic development of the Delta region was highly stimulated. Safety against flooding is nowadays on a high standard, nonetheless [[sea level rise]] and [[climate change]] require ongoing attention and investments.<br />
<br />
[[Image:foto1.jpg|thumb|right|300px|Figure 1: Agriculture in the Dutch Delta]]<br />
[[Image:foto2.jpg|thumb|right|300px|Figure 2: Agriculture in the Dutch Delta]]<br />
<br />
While some environmental drawbacks were expected at the time, the Delta currently faces many ecological problems and possible solutions require high investments for mitigation or restoration. These problems are related to the disappearance of the characteristic freshwater-saltwater transitions and estuarine dynamics. One of these ecological problems is the excessive growth of blue-green [[algae]] in the Volkerak-Zoom lake (VZ-lake). The Dutch Government regards the re-establishment of estuarine dynamics in the Delta an important solution to restore the ecological quality (whilst preserving safety against flooding and transportation possibilities) (Ministeries van VROM et al. 2004<ref>Ministeries van VROM, LNV, VenW , and EZ. (2004). Nota Ruimte - Ruimte voor ontwikkeling / National Spatial Strategy</ref>). This policy, together with the perspectives of [[sea level rise]], lower river flows and increasing risk of too dry summers periods result in the common finding that salinization of the Delta is becoming a major issue for agriculture.<br />
<br />
The question is thus “How to combine the restoration of estuarine dynamics with freshwater supply for agriculture in a sustainable way?”. The national government asked the [http://www.delta-wateren.nl Delta Provinces] to start a fundamental discussion with different stakeholders on this issue. Because problems are very context-specific, it was decided to have consecutive dialogues in different areas of the Delta. The first project is a pilot-project about safeguarding freshwater supply for agriculture on the islands Tholen and St. Philipsland. Farmers on these islands extract from the VZ-lake freshwater for agricultural purposes. This paper describes the case study concerning this pilot-project executed in 2007.<br />
<br />
==Case study analysis==<br />
===Methodology===<br />
Objective of the case study is to get insight in problem structuring by analyzing the role of interaction, problem perceptions and knowledge. Problem structuring is an interactive process in which all relevant [[stakeholders]] develop a joint formulation of the problem and its solutions (Hisschemöller 1993<ref name=Hissch93>Hisschemöller, M. J. (1993). De democratie van problemen : de relatie tussen de inhoud van beleidsproblemen en methoden van politieke besluitvorming, PhD thesis, Amsterdam : VU Uitgeverij</ref>; Rosenhead 1989<ref name=Rosenhead>Rosenhead, J. (1989). Rational analysis for a problematic world : problem structuring methods for complexity, uncertainty and conflict, John Wiley & Sons, Chichester</ref>). Ideally, this formulation is based on <i>‘negotiated knowledge’</i>, i.e. knowledge which is agreed upon and valid (see e.g. De Bruijn et al. 2002<ref name=Bruijn> De Bruijn, H., Ten Heuvelhof, E. F., and In 't Veld, R. J. (2002). Process management: why project management fails in complex decision making processes, Kluwer Academic Publishers, Dordrecht </ref>; Van de Riet 2003<ref name=Riet>Van de Riet, A. W. T. (2003). Policy analysis in multi-actor policy settings : navigating between negotiated nonsense and superfluous knowledge. PhD thesis, Technische Universiteit Delft, Delft : Eburon Publishers</ref>). In the case study, problem structuring is analyzed along three tracks: <br />
# Participatory process: How did the interactive process develop? E.g. which actors were involved, what was the scope of the process and which interactive activities were organized? <br />
# Perceptions: How are [[stakeholders|stakeholders’]] problem perceptions developing? This analysis includes the analysis of normative elements (interests, objectives, criteria) and cognitive elements (view of the world, the problem, chances and bottlenecks). <br />
# Knowledge: How is the content of the knowledge base developing? This analysis includes the role of different actors in the production of knowledge. <br />
<br />
These three tracks are analysed against the background and history of the interactive process and its social and natural environment. For the analysis different methods and sources are used, such as observations during the interactive process, analysis of research reports and project documents, interview reports, news articles and internet sources and interviews with process managers. <br />
<br />
===The participatory process===<br />
Objective of the pilot-project is <i>“to develop a shared insight and agreement about the most desirable direction for solutions or development”</i> with respect to freshwater supply for agriculture given the possible freshwater situations in the Dutch Delta. To realize this objective, the responsible government body (the Delta Council) decided to start a participatory process. Participating [[stakeholders]] are local farmers; representatives from the agricultural interest organization; agricultural business; national, regional and local nature societies; local and regional water managers; local and provincial public servants and delegates. The process design consists of several converging and diverging phases: analysis of chances and bottlenecks, the generation of solutions, and the adaptation of possible solutions. Every phase starts with a broad scope after which selection takes place. A broad scope is characteristic for the discussion, no problem formulations are excluded. The result of the [[Problem structuring in decision-making processes|participatory process]] goes beyond expectations, all [[stakeholders]] agreed upon one direction for solutions given the prior condition of a saline Volkerak-zoom lake. This solution includes the safeguarding of freshwater supply for agriculture by means of a pipeline supplying water from a river upstream, after which steps can be taken to re-establish estuarine dynamics.<br />
<br />
===Perceptions===<br />
At the outset of the discussion, [[stakeholders|stakeholders’]] perceptions diverge and people do not understand each other. The exchange of perceptions (chances, bottlenecks, possible solutions) during several workshops and an excursion through the area enhanced convergence of perceptions and mutual understanding. For every participants one of more elements of their problem formulation changed during the process. But, because interests and objectives diverge, they do not become identical. Still, [[stakeholders]] reach an agreement about the most preferable solution. According to Koppenjan and Klijn (2004<ref name=Koppenjan> Koppenjan, J. F. M., and Klijn, E. (2004). Managing uncertainties in networks : a network approach to problem solving and decision making Routledge, London [etc.] </ref>) cognitive and strategic learning contribute directly to the outcomes of participatory policy processes. Cognitive learning refers to “the increased knowledge and insight about the nature of the problem, possible solutions, and their consequences” (p. 125<ref name=Koppenjan/>). Strategic learning involves “parties growing consciences of each others involvement and their mutual dependencies” (p. 127<ref name=Koppenjan/>). How these learning processes develop and their impact relates to the background of participants. Especially for representatives from the public sector it is difficult to change objectives, because they are incorporated in an organization and bound to policy and promises.<br />
<br />
===Knowledge===<br />
At the outset of the process, the process managers present a note concerning the process to participants which summarizes existing information and research. This note aims to provide a starting-point for the discussion. The note presents findings from previous research, but also bottlenecks experienced by [[stakeholders]] and their divergent views on sustainability (see Reijs 2006a<ref>Reijs, T. A. M. (2006a). Informatie ten behoeve van fundamentele discussie zoetwatersituatie ZW-Delta: Pilot Tholen/St. Philipsland. TNO Bouw en Ondergrond, Innovatie en Ruimte, Delft </ref>). The most relevant research report goes into the future of agriculture in relation to freshwater supply (Stuyt et al. 2006<ref>Stuyt, L. C. P. M., Bakel, P. J. T. V., Kroes, J. G., Bos, E. J., Elst, M. V. d., Pronk, B., Rijk, P. J., Clevering, O. A., Dekking, A. J. G., Voort, M. P. J. V. d., Wolf, M. D., and Brandenburg, W. A. (2006). Transitie en toekomst van de Deltalandbouw; indicatoren voor de ontwikkeling van de land- en tuinbouw in de Zuidwestelijke Delta van Nederland. Alterra, Wageningen, The Netherlands</ref>). The findings of this report appear to conflict with the experiences and expectations from participating farmers. The development of possible solutions with representatives from the agricultural sector creates a substantive breakthrough. In the same period, the process managers also consult the nature sector and government organizations. During these meetings [[stakeholders]] are enhanced to contribute with their own knowledge and experiences. Consequently, the content of the conclusions in the closing report are a mix of knowledge from professional experts (laid down in research reports) and [[stakeholders|stakeholder]] knowledge (based on their experiences). Although some reservations are made, the created knowledge base is agreed upon by all participants of the process. A reservation is made by the government, asking for an additional societal costs-benefits analysis (although costs and benefits have been calculated). On behalf of the nature sector, figures are accompanied by the remark that they need to be verified by professional experts (see Reijs 2006b<ref>Reijs, T. A. M. (2006b). Verslag en resultaten van de brede discussie zoetwatersituatie voor de landbouw in de Delta: Pilot Tholen & St. Philipsland. TNO Bouw en ondergrond, Innovatie en Ruimte, Delft</ref>).<br />
<br />
[[Image:problemstructuring_2.jpg|thumb|750px|centre|Figure 1: Knowledge and perceptions in problem structuring]]<br />
<br />
==Conclusions==<br />
Aim of this case study research is to get insight in problem structuring. This section presents some conclusions on problem structuring. These conclusions are based on the presented case study, our experiences with another case study project (an interactive process on sediment management) and a literature review on [[Deliberation support tools|problem structuring]]. <br />
<br />
Problem structuring is not a clear-cut, isolated process. A participatory interactive process does not start with blank perceptions or a blank knowledge base. Perceptions and knowledge are constantly developing before, during and after the participatory process. Besides this, developments within the social and natural environment also influence a participatory process (Koppenjan and Klijn 2004<ref name=Koppenjan/>). The dynamics of participatory processes ask for adaptive process management (Edelenbos and Klijn 2006<ref>Edelenbos, J., and Klijn, E. H. (2006). Managing stakeholder involvement in decision making: A comparative analysis of six interactive processes in the Netherlands. Journal Of Public Administration Research And Theory, 16(3), 417-446</ref>). The case study supports the idea that process management should be adaptive. Moreover, the case study shows the importance of an open process approach, so that the divergent perceptions of all participants are included. <br />
<br />
The case study shows that [[stakeholders|stakeholders’]] perceptions adjust because [[stakeholders]] learn cognitively and strategically. The case study also supports the idea that to create context-specific knowledge, [[stakeholders|stakeholder]] knowledge and knowledge from professional experts are useful sources of knowledge (Eshuis and Stuiver 2005<ref name=Eshuis> Eshuis, J., and Stuiver, M. (2005). Learning in context through conflict and alignment: Farmers and scientists in search of sustainable agriculture. Agriculture And Human Values, 22(2), 137-148</ref>). An advantage of using [[stakeholders|stakeholder]] knowledge is that it contributes to reaching an agreement, since [[stakeholders]] are more likely to accept information if they have been involved in the production (De Bruijn et al. 2002<ref name=Bruijn/>); Eshuis and Stuiver 2005<ref name=Eshuis/>). However, not all [[stakeholders]] (especially government partners not) confirm that although [[stakeholders|stakeholder]] knowledge is different from knowledge from professional experts, that it is just as valuable (Nowotny 2003<ref> Nowotny, H. (2003). Democratising expertise and socially robust knowledge. Science and Public Policy, 30(3), 151</ref>; Rinaudo and Garin 2005<ref> Rinaudo, J. D., and Garin, P. (2005). The benefits of combining lay and expert input for water-management planning at the watershed level. Water Policy, 7(3), 279</ref>). In the case study, the connection of different types of knowledge was taken care of by process managers. Thus, it is not necessary to have a face-to-face dialogue between professional experts and stakeholders if process managers can take care of this.<br />
<br />
==See also==<br />
[[Problem structuring in decision-making processes]]<br />
<br />
More information on problem structuring is also presented in the [[Deliberation support tools]] section.<br />
<br />
The case study is presented before in: [http://www.wem.ctw.utwente.nl/onderwijs/afstuderen/afstudeerverslagen/2007/Kruijf.pdf De Kruijf, J. (2007). <i>Problem structuring in interactive decision-making processes: How interaction, problem perceptions and knowledge contribute to a joint formulation of a problem and its solutions</i>, Master's thesis, University of Twente, Enschede]. This report is available as TNO-report, ref. nr 2007-I&R-065-KFJ-PEM.<br />
<br />
More information with respect to the context of the broad discussion is available at the website of the Delta Council: http://www.delta-wateren.nl/<br />
<br />
==References==<br />
<references/><br />
<br />
<br />
{{author<br />
|AuthorID= 15610<br />
|AuthorFullName=Joanne Vinke-De Kruijf<br />
|AuthorName=Joanne}}<br />
<br />
[[Category:Coastal urban development]]<br />
[[Category:Coastal agriculture]]<br />
[[Category:Practice, projects and case studies in coastal management]]<br />
[[Category:Theme_1]]<br />
[[Category:Participation and governance in coastal management]]<br />
[[Category: Case studies]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Salinization_adaptation_and_freshwater_supply_for_agriculture_in_the_Dutch_Delta&diff=30653
Salinization adaptation and freshwater supply for agriculture in the Dutch Delta
2009-07-09T13:43:07Z
<p>Wouter Kreiken: featured</p>
<hr />
<div>{{featured}}<br />
<br />
This article describes a case study, which provides an example of [[Problem structuring in decision-making processes|structuring problems]] in order to improve [[Stakeholder analysis|stakeholder dialogue]]. It uses the Delta area of the Netherlands and in particular focuses on issues surrounding the restoration of estuarine dynamics and [[sustainable]] supply of freshwater for agriculture.<br />
<br />
==Introduction==<br />
[[Image:foto1.jpg|thumb|right|300px|Figure 1: Agriculture in the Dutch Delta]]<br />
[[Image:foto2.jpg|thumb|right|300px|Figure 2: Agriculture in the Dutch Delta]]<br />
The delta of the rivers Rhine, Meuse and Scheldt, located in the Southwest of the Netherlands, is unique for its large water systems surrounded by [[dikes]] and [[dams]] to protect the hinterland against flooding. With the construction of a [[storm surge]] barrier in the Eastern Scheldt in 1986, the Dutch Delta Works safety restoration programs were completed. The construction of the Delta Works made the Southwest of the Netherlands safer, more accessible and several newly created freshwater basins provided opportunities for drinking water supply and agriculture. The hydraulic engineering projects have been executed allowing ecological concerns to be taken into account to the best available knowledge. As a result the economic development of the Delta region was highly stimulated. Safety against flooding is nowadays on a high standard, nonetheless [[sea level rise]] and [[climate change]] require ongoing attention and investments.<br />
<br />
While some environmental drawbacks were expected at the time, the Delta currently faces many ecological problems and possible solutions require high investments for mitigation or restoration. These problems are related to the disappearance of the characteristic freshwater-saltwater transitions and estuarine dynamics. One of these ecological problems is the excessive growth of blue-green [[algae]] in the Volkerak-Zoom lake (VZ-lake). The Dutch Government regards the re-establishment of estuarine dynamics in the Delta an important solution to restore the ecological quality (whilst preserving safety against flooding and transportation possibilities) (Ministeries van VROM et al. 2004<ref>Ministeries van VROM, LNV, VenW , and EZ. (2004). Nota Ruimte - Ruimte voor ontwikkeling / National Spatial Strategy</ref>). This policy, together with the perspectives of [[sea level rise]], lower river flows and increasing risk of too dry summers periods result in the common finding that salinization of the Delta is becoming a major issue for agriculture.<br />
<br />
The question is thus “How to combine the restoration of estuarine dynamics with freshwater supply for agriculture in a sustainable way?”. The national government asked the [http://www.delta-wateren.nl Delta Provinces] to start a fundamental discussion with different stakeholders on this issue. Because problems are very context-specific, it was decided to have consecutive dialogues in different areas of the Delta. The first project is a pilot-project about safeguarding freshwater supply for agriculture on the islands Tholen and St. Philipsland. Farmers on these islands extract from the VZ-lake freshwater for agricultural purposes. This paper describes the case study concerning this pilot-project executed in 2007.<br />
<br />
==Case study analysis==<br />
===Methodology===<br />
Objective of the case study is to get insight in problem structuring by analyzing the role of interaction, problem perceptions and knowledge. Problem structuring is an interactive process in which all relevant [[stakeholders]] develop a joint formulation of the problem and its solutions (Hisschemöller 1993<ref name=Hissch93>Hisschemöller, M. J. (1993). De democratie van problemen : de relatie tussen de inhoud van beleidsproblemen en methoden van politieke besluitvorming, PhD thesis, Amsterdam : VU Uitgeverij</ref>; Rosenhead 1989<ref name=Rosenhead>Rosenhead, J. (1989). Rational analysis for a problematic world : problem structuring methods for complexity, uncertainty and conflict, John Wiley & Sons, Chichester</ref>). Ideally, this formulation is based on <i>‘negotiated knowledge’</i>, i.e. knowledge which is agreed upon and valid (see e.g. De Bruijn et al. 2002<ref name=Bruijn> De Bruijn, H., Ten Heuvelhof, E. F., and In 't Veld, R. J. (2002). Process management: why project management fails in complex decision making processes, Kluwer Academic Publishers, Dordrecht </ref>; Van de Riet 2003<ref name=Riet>Van de Riet, A. W. T. (2003). Policy analysis in multi-actor policy settings : navigating between negotiated nonsense and superfluous knowledge. PhD thesis, Technische Universiteit Delft, Delft : Eburon Publishers</ref>). In the case study, problem structuring is analyzed along three tracks: <br />
# Participatory process: How did the interactive process develop? E.g. which actors were involved, what was the scope of the process and which interactive activities were organized? <br />
# Perceptions: How are [[stakeholders|stakeholders’]] problem perceptions developing? This analysis includes the analysis of normative elements (interests, objectives, criteria) and cognitive elements (view of the world, the problem, chances and bottlenecks). <br />
# Knowledge: How is the content of the knowledge base developing? This analysis includes the role of different actors in the production of knowledge. <br />
<br />
These three tracks are analysed against the background and history of the interactive process and its social and natural environment. For the analysis different methods and sources are used, such as observations during the interactive process, analysis of research reports and project documents, interview reports, news articles and internet sources and interviews with process managers. <br />
<br />
===The participatory process===<br />
Objective of the pilot-project is <i>“to develop a shared insight and agreement about the most desirable direction for solutions or development”</i> with respect to freshwater supply for agriculture given the possible freshwater situations in the Dutch Delta. To realize this objective, the responsible government body (the Delta Council) decided to start a participatory process. Participating [[stakeholders]] are local farmers; representatives from the agricultural interest organization; agricultural business; national, regional and local nature societies; local and regional water managers; local and provincial public servants and delegates. The process design consists of several converging and diverging phases: analysis of chances and bottlenecks, the generation of solutions, and the adaptation of possible solutions. Every phase starts with a broad scope after which selection takes place. A broad scope is characteristic for the discussion, no problem formulations are excluded. The result of the [[Problem structuring in decision-making processes|participatory process]] goes beyond expectations, all [[stakeholders]] agreed upon one direction for solutions given the prior condition of a saline Volkerak-zoom lake. This solution includes the safeguarding of freshwater supply for agriculture by means of a pipeline supplying water from a river upstream, after which steps can be taken to re-establish estuarine dynamics.<br />
<br />
===Perceptions===<br />
At the outset of the discussion, [[stakeholders|stakeholders’]] perceptions diverge and people do not understand each other. The exchange of perceptions (chances, bottlenecks, possible solutions) during several workshops and an excursion through the area enhanced convergence of perceptions and mutual understanding. For every participants one of more elements of their problem formulation changed during the process. But, because interests and objectives diverge, they do not become identical. Still, [[stakeholders]] reach an agreement about the most preferable solution. According to Koppenjan and Klijn (2004<ref name=Koppenjan> Koppenjan, J. F. M., and Klijn, E. (2004). Managing uncertainties in networks : a network approach to problem solving and decision making Routledge, London [etc.] </ref>) cognitive and strategic learning contribute directly to the outcomes of participatory policy processes. Cognitive learning refers to “the increased knowledge and insight about the nature of the problem, possible solutions, and their consequences” (p. 125<ref name=Koppenjan/>). Strategic learning involves “parties growing consciences of each others involvement and their mutual dependencies” (p. 127<ref name=Koppenjan/>). How these learning processes develop and their impact relates to the background of participants. Especially for representatives from the public sector it is difficult to change objectives, because they are incorporated in an organization and bound to policy and promises.<br />
<br />
===Knowledge===<br />
At the outset of the process, the process managers present a note concerning the process to participants which summarizes existing information and research. This note aims to provide a starting-point for the discussion. The note presents findings from previous research, but also bottlenecks experienced by [[stakeholders]] and their divergent views on sustainability (see Reijs 2006a<ref>Reijs, T. A. M. (2006a). Informatie ten behoeve van fundamentele discussie zoetwatersituatie ZW-Delta: Pilot Tholen/St. Philipsland. TNO Bouw en Ondergrond, Innovatie en Ruimte, Delft </ref>). The most relevant research report goes into the future of agriculture in relation to freshwater supply (Stuyt et al. 2006<ref>Stuyt, L. C. P. M., Bakel, P. J. T. V., Kroes, J. G., Bos, E. J., Elst, M. V. d., Pronk, B., Rijk, P. J., Clevering, O. A., Dekking, A. J. G., Voort, M. P. J. V. d., Wolf, M. D., and Brandenburg, W. A. (2006). Transitie en toekomst van de Deltalandbouw; indicatoren voor de ontwikkeling van de land- en tuinbouw in de Zuidwestelijke Delta van Nederland. Alterra, Wageningen, The Netherlands</ref>). The findings of this report appear to conflict with the experiences and expectations from participating farmers. The development of possible solutions with representatives from the agricultural sector creates a substantive breakthrough. In the same period, the process managers also consult the nature sector and government organizations. During these meetings [[stakeholders]] are enhanced to contribute with their own knowledge and experiences. Consequently, the content of the conclusions in the closing report are a mix of knowledge from professional experts (laid down in research reports) and [[stakeholders|stakeholder]] knowledge (based on their experiences). Although some reservations are made, the created knowledge base is agreed upon by all participants of the process. A reservation is made by the government, asking for an additional societal costs-benefits analysis (although costs and benefits have been calculated). On behalf of the nature sector, figures are accompanied by the remark that they need to be verified by professional experts (see Reijs 2006b<ref>Reijs, T. A. M. (2006b). Verslag en resultaten van de brede discussie zoetwatersituatie voor de landbouw in de Delta: Pilot Tholen & St. Philipsland. TNO Bouw en ondergrond, Innovatie en Ruimte, Delft</ref>).<br />
<br />
[[Image:problemstructuring_2.jpg|thumb|750px|centre|Figure 1: Knowledge and perceptions in problem structuring]]<br />
<br />
==Conclusions==<br />
Aim of this case study research is to get insight in problem structuring. This section presents some conclusions on problem structuring. These conclusions are based on the presented case study, our experiences with another case study project (an interactive process on sediment management) and a literature review on [[Deliberation support tools|problem structuring]]. <br />
<br />
Problem structuring is not a clear-cut, isolated process. A participatory interactive process does not start with blank perceptions or a blank knowledge base. Perceptions and knowledge are constantly developing before, during and after the participatory process. Besides this, developments within the social and natural environment also influence a participatory process (Koppenjan and Klijn 2004<ref name=Koppenjan/>). The dynamics of participatory processes ask for adaptive process management (Edelenbos and Klijn 2006<ref>Edelenbos, J., and Klijn, E. H. (2006). Managing stakeholder involvement in decision making: A comparative analysis of six interactive processes in the Netherlands. Journal Of Public Administration Research And Theory, 16(3), 417-446</ref>). The case study supports the idea that process management should be adaptive. Moreover, the case study shows the importance of an open process approach, so that the divergent perceptions of all participants are included. <br />
<br />
The case study shows that [[stakeholders|stakeholders’]] perceptions adjust because [[stakeholders]] learn cognitively and strategically. The case study also supports the idea that to create context-specific knowledge, [[stakeholders|stakeholder]] knowledge and knowledge from professional experts are useful sources of knowledge (Eshuis and Stuiver 2005<ref name=Eshuis> Eshuis, J., and Stuiver, M. (2005). Learning in context through conflict and alignment: Farmers and scientists in search of sustainable agriculture. Agriculture And Human Values, 22(2), 137-148</ref>). An advantage of using [[stakeholders|stakeholder]] knowledge is that it contributes to reaching an agreement, since [[stakeholders]] are more likely to accept information if they have been involved in the production (De Bruijn et al. 2002<ref name=Bruijn/>); Eshuis and Stuiver 2005<ref name=Eshuis/>). However, not all [[stakeholders]] (especially government partners not) confirm that although [[stakeholders|stakeholder]] knowledge is different from knowledge from professional experts, that it is just as valuable (Nowotny 2003<ref> Nowotny, H. (2003). Democratising expertise and socially robust knowledge. Science and Public Policy, 30(3), 151</ref>; Rinaudo and Garin 2005<ref> Rinaudo, J. D., and Garin, P. (2005). The benefits of combining lay and expert input for water-management planning at the watershed level. Water Policy, 7(3), 279</ref>). In the case study, the connection of different types of knowledge was taken care of by process managers. Thus, it is not necessary to have a face-to-face dialogue between professional experts and stakeholders if process managers can take care of this.<br />
<br />
==See also==<br />
[[Problem structuring in decision-making processes]]<br />
<br />
More information on problem structuring is also presented in the [[Deliberation support tools]] section.<br />
<br />
The case study is presented before in: [http://www.wem.ctw.utwente.nl/onderwijs/afstuderen/afstudeerverslagen/2007/Kruijf.pdf De Kruijf, J. (2007). <i>Problem structuring in interactive decision-making processes: How interaction, problem perceptions and knowledge contribute to a joint formulation of a problem and its solutions</i>, Master's thesis, University of Twente, Enschede]. This report is available as TNO-report, ref. nr 2007-I&R-065-KFJ-PEM.<br />
<br />
More information with respect to the context of the broad discussion is available at the website of the Delta Council: http://www.delta-wateren.nl/<br />
<br />
==References==<br />
<references/><br />
<br />
<br />
{{author<br />
|AuthorID= 15610<br />
|AuthorFullName=Joanne Vinke-De Kruijf<br />
|AuthorName=Joanne}}<br />
<br />
[[Category:Coastal urban development]]<br />
[[Category:Coastal agriculture]]<br />
[[Category:Practice, projects and case studies in coastal management]]<br />
[[Category:Theme_1]]<br />
[[Category:Participation and governance in coastal management]]<br />
[[Category: Case studies]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Reduction_of_uncertainties_through_Data_Model_Integration_(DMI)&diff=30652
Reduction of uncertainties through Data Model Integration (DMI)
2009-07-09T13:42:00Z
<p>Wouter Kreiken: featured</p>
<hr />
<div>{{featured}}<br />
<br />
This article describes how [[data]] and models can be combined in a structured way, in order to reduce uncertainties. This process is also called [[Data Model Integration (DMI)]]. This article describes the criteria which can be used to evaluate models, how to reduce uncertainties, and two DMI-approaches: [[model calibration]] and data assimilation. <br />
<br />
==Introduction==<br />
Application of techniques for data model integration (DMI) are increasingly used in many fields of science, finance, economics, etc. Every day examples are improvement of geophysical model descriptions (flows, water levels, waves), improvements and optimization of daily weather forecasts, detection of errors in data series, on-line identification of stolen credit card use, detection of malfunctioning components in manufacturing processes. How DMI can be used to support monitoring and assessment of marine systems is also schematized in Figure 1. <br />
<br />
The one common element is the prior knowledge of the behaviour of a process in the form of an explicit model description, or a set of characteristic data. The second common element is a set of independent or new data. Neither the description of the behaviour and the data are 100% certain – they have uncertainties associated with them. If one has information on the (statistical) nature of the uncertainties, smart mathematical techniques can be used to combine these two information sources and generate new or improved information. Two possible DMI-approaches are: <br />
# '''[[Model calibration]]''' and calibration or parameter estimation techniques: This approach aims to improve the model and may result in an improved model description (less uncertain). <br />
# (Sequential) '''data assimilation''' and data assimilation techniques: This may results in an improved forecast, detection of significant deviation from established patterns (faulty component, credit card use,…).<br />
<br />
[[Image:DMI.jpg|thumb|750px|centre|Figure 1: Data Model Integration approach to support the monitoring and assessment of marine systems]]<br />
<br />
==Error criteria and Goodness of Fit==<br />
In geophysical science, DMI is commonly used for model improvement ([[model calibration]]) and optimization of operational forecasts (data assimilation). Application of DMI essentially starts with choosing the model quantities of interest that need to be evaluated and compared with data. A quantitative measure needs to be chosen or defined that expresses the agreement between these quantities and the field data. Instead of agreement, we often also use the words “difference”, “disagreement”, “mismatch”, “misfit” or “error”. Least squares criteria are commonly used measures for this, since they are symmetric and have favourable properties from a theoretical point of view. Another name for a least squares criterion is ''"Cost Function (CF)"''. This should be minimal to have the best agreement. Another formulation is a ''"Goodness-of-Fit (GoF)"'' criterion (most commonly also defined as a quadratic term). The GoF needs to be maximized to obtain maximum agreement. The relation is: GoF = - log (CF). The key issue of using such quantitative measures is that they are compact, quantitative, objective, reproducible, transferable, and are easy to use in automated evaluation procedures and software.<br />
<br />
==Role and reduction of uncertainties==<br />
<br />
===Uncertainties in models and data===<br />
Models are never “true”. Even the very best models provide schematised representations of the real world. Examples are flow models, models for transport and spreading, models for wave propagation, rainfall run-off models and morphological models. They are limited to the representation of those real world phenomena that are of specific practical interest, characterised by associated temporal and spatial scales of interest. In the derivation of these models all kind of simplifications and approximations have been applied. These are often formulated as “errors” or “uncertainties” in the model. These uncertainties occur in: <br />
# the model concept as such,<br />
# in the various model parameters, <br />
# the driving forces, <br />
# in the modelling result. <br />
# Moreover, a model uncertainty of general nature is associated with the representativity of model results for observed entities.<br />
<br />
Equally, field measurements or observations also suffer from errors or uncertainties. These may be the result of:<br />
# equipment accuracy, <br />
# instrument drift, <br />
# equipment fouling or malfunctioning, <br />
# temporal and spatial sampling frequency, <br />
# data processing and interpretation, <br />
# spatial and temporal representativeness, and other.<br />
<br />
As a result of all this, mismatches of model results and observations are virtually unavoidable. Moreover, both sources of information involve errors in their estimate for the true state of the system. The errors in the model at one hand, and measurements on the other, can be of very different type, origin, and magnitude.<br />
<br />
===Stochastic models===<br />
By adding terms for the model uncertainties on the deterministic equations for the model the model is converted into a so-called "stochastic model". Similarly, terms for the observation uncertainties are added to the equation that can formally be written for the measurements. The data assimilation procedures use these new stochastic equations in order to derive the desired optimal result by suitable combination.<br />
<br />
===Formulation of uncertainty===<br />
An important first step to reduce uncertainty is prescribing known (or assumed) uncertainties in the models and data. When dealing with dynamic and spatially distributed models the temporal and spatial (statistical) properties must be considered carefully. In fact, the time and length scales of the uncertainties should be consistent with the process(es) being modelled. Therefore, as for the actual (deterministic) numerical model, process and system knowledge should be used as much as possible in the formulation of the so-called “uncertainty model”. The better the uncertainty characteristics of the model and its various parameters, and data series, etc. are known, the more accurate and effective the DMI-technique can be in estimating the desired result and optimising the estimate of a system state and reduction of the uncertainty in that estimate.<br />
<br />
===Reduction of uncertainty through DMI===<br />
Depending on the DMI algorithms that are used, and/or correctness of assumptions, a combination of data and model with known uncertainty (in statistical sense) can lead to (statistically) optimal estimate for the system’s state. Such optimal estimates are achieved when the weights in the combination of model outcomes and measurements are based on the uncertainties in both. This is illustrated by a simple example, in which <math>\xi\,</math><sub>M</sub> is a model result for some system state variable at some spatial position and time, and the spread <math>\sigma\,</math><sub>M</sub> is its uncertainty. Similarly, <math>\xi\,</math><sub>0</sub> and <math>\sigma \,</math><sub>0</sub> are the corresponding measured value and the uncertainty in the measurement. A (statistically) optimal combination of these two estimates leads to the estimate [[Image:image5.png]] <br />
<br />
with a spread <sub>[[Image:image6.png]]</sub> that satisfies <sub><sub><sub>[[Image:image7.png]]</sub></sub></sub>.<br />
<br />
Clearly the uncertainty in the combined estimate is less that the uncertainty in the individual estimates.<br />
This example reflects the essence of DMI and in applications of structured DMI techniques to real life numerical models (dealing with many grid points and state variables, complex and non-linear dynamics, high model computation times, etc.) the above principle is ‘merely’ generalised in an appropriate way.<br />
<br />
==Calibration of models==<br />
<br />
===Objective===<br />
The main goal of a [[model calibration]] is the identification of uncertain model parameters. The model is assumed to be perfect, except for a number of not well known parameters or “control variables”. These control variables may originate from parameterisations of uncertain coefficients in the model, initial or boundary conditions, and/or the external forcing. Measurements are used to obtain estimates for these parameters. These estimates are the values of these parameters for which, in some sense, the model outcomes agree best with the measurements. Therefore calibration is often also called “model fitting” or “parameter estimation”. Uncertainties in the measurements can be taken into account, and be used in the definition of the calibration criterion (see below) and the assessment of the uncertainties in the identified model parameters. [[Model calibration]] should not be confused with [[model validation]], for which a set of independent data is used and model forcing and parameters are fixed.<br />
<br />
===Approach===<br />
Calibration is usually translated into an optimisation problem where some Goodness of Fit (GOF) or Cost Function (CF) must be maximised or minimised. A GOF or CF provides a formalised and quantitative description of the agreement between measurements and the corresponding model outcomes. In this way the (main) features or targets that the model must reproduce can be specified. In the formulation of the GOF or CF the uncertainties in the data can explicitly be taken into account. For example, data points with the highest accuracy will have the largest “weight” in – or contribution to - the CF, and thus have the largest impact on the final estimate for the model parameters.<br />
<br />
===Statistical interpretation===<br />
Although calibration is often formulated and carried out in a deterministic sense, a close relation to statistics can be recognised. In fact, a statistical interpretation can be assigned to the comparison of the model outcomes on one hand, and the measurements and (the statistical description of) their uncertainties on the other. On this basis a GOF or CF can be derived, rather than “independently” prescribed. For example, when the estimation is based on Maximum Likelihood (MLH), cost functions of type least squares will be found. The MLH formalism will then automatically also provide a recipe for computing the uncertainties in the parameters’ estimates.<br />
<br />
===Calibration Techniques===<br />
When a model calibration is formulated as an optimisation of a GOF or CF, the parameter estimation is virtually a minimisation problem. For special cases, as for example linear models, this minimisation can be done analytically. In the other case it must be relied on numerical techniques. Because of their efficiency (in the sense of the number of model evaluations that is required to find the minimum) gradient descent techniques as for example conjugate gradient or quasi-Newton methods are by far most efficient. A main problem is often the evaluation of the derivatives of the CF, however. For many data driven models (analytical regression models, empirical formulae, Neural Networks, etc.) the derivatives can usually straightforwardly and analytically be computed. For large scale dynamical numerical (flow, wave, transport, morphological, meteorological) models, with often a large number of uncertain parameters, this is certainly not the case and for the computation of gradients the so called adjoint model can be used. The adjoint model is derived from the original model by means of a variational analysis. For descriptions and applications of adjoint modelling see e.g. Chavent (1980<ref>Chavent, G. 1980.Identification of distributed parameter systems: about the output least square method, its implementation, and identifiability. In Iserman R. (ed), ''Proc. 5th IFAC Symposium on Identification and System Parameter Estimation''. I: 85-97. New York: Pergamon Press.</ref>), Panchang and O’Brien (1990<ref>Panchang, V.G., O’Brien, J.J. 1990. On the determination of hydraulic model parameters using the adjoint state formulation. In Davies A.M. (ed.), ''Modelling Marine Systems'', Volume I, Chapter 2: 5-18. Boca Raton, Florida, CRC Press, Inc. </ref>), Van den Boogaard et al. (1993<ref><br />
Van den Boogaard, H.F.P., Hoogkamer, M.J.J. Heemink, A.W. 1993. Parameter identification in particle models. ''Stochastic Hydrology and Hydraulics'' 9(2): 109-130.</ref>), Lardner et al. (1993<ref>Lardner, R.W., Al-Rabeh, A.H., Gunay, N. 1993. Optimal estimation of parameters for a two-dimensional model of the Arabian Gulf. ''Journal of Geophysical Research''. 98(C10): 229-242.</ref>), Mouthaan et al. (1994<ref>Mouthaan, E.E.A., A.W. Heemink and K.B. Robaczeswka, 1994.Assimilation of ERS-1 altimeter data in a tidal model of the Continental Shelf, ''Deutsche Hydrographische Zeitschrift'', 285-329.</ref>). A main practical disadvantage of the adjoint is the time and cost of its implementation, however. For computationally less demanding models gradient free (local or global search) minimisation techniques may serve as a reasonable alternative for gradient based methods as long as the number of uncertain parameters is sufficiently low (less than 10, say). An example is the DUD (Doesn’t Use Derivatives) technique (Ralston and Jennrich, 1978<ref>Ralston, M.L. and R.I. Jennrich, 1978. Dud, a derivative-free algorithm for nonlinear least squares. ''Technometrics'', 20, 7-14. </ref>).<br />
<br />
==Sequential data assimilation in dynamic (time-stepping) models==<br />
<br />
===Objective===<br />
Even a well calibrated model may not perform perfectly in forecast mode. Prediction errors can be due to several sources of uncertainties as for example unresolved inaccuracies in the model and/or its parameters, non-stationarities, uncertainties in the elements forming the model’s external forcing, etc. To improve a model’s skill for operational and/or real time predictions, on-line or sequential DMI or data assimilation techniques are often used. <br />
<br />
===Approach===<br />
The usual approach is to construct a statistical description for all model and measurement uncertainties. In this way the uncertainties are modelled in a statistical way rather than strictly physical. The original deterministic model is thus embedded in a stochastic environment. The actual data assimilation then involves a consistent (spatial and temporal) integration of all sources of information, i.e. the model and all observations so far available. Within this combination of model and data the statistics of their uncertainties must carefully be taken into account. After this integration for the period that measurements are available, an optimal initialisation of the model is obtained for a subsequent forecast simulation (in prediction mode). This integration of data and model can be repeated every time when new observations become available – the time window of assimilation and forecasts proceeds stepwise forward in time. In this way the model can adapt to changing system conditions. <br />
<br />
===Simple techniques===<br />
The simplest technique for this is “data insertion”. The model is propagated forward in time until a time is reached at which measurements are available. The model values are simply overwritten with measurement values. This overwriting leaves the model unbalanced and typically injects bursts of gravity noise (spurious modes propagating with the speed of gravity) into the model solution. This therefore is generally not a satisfactory method. <br />
A further method is Optimal Interpolation. This method modifies model results whenever observations are encountered by adding some fraction of the difference between modelled and measured quantities to the modelled fields, the fraction being determined by the presumably known error covariance structure of the model solution. To the extent that the error covariances are correctly modelled, this method is statistically optimal. It still results in some gravity wave insertion, and extensive efforts have been made to develop so-called “non-linear normal mode initialisation” procedures to remove the effect of this inserted noise from the subsequent analysis. <br />
<br />
===Kalman filtering===<br />
Kalman filtering (Kalman, 1960<ref>Kalman R. E. (1960).“A new approach to linear filtering and prediction problems,” ''Basic Engineering'', pp. 35-45.</ref>; Kalman and Bucy, 1961<ref>Kalman R. E. and Bucy R. S. (1961). “New Results in linear filtering and prediction theory,” ''Basic Engineering'', 83D, pp. 95-108.<br />
</ref>) is nowadays a commonly applied procedure for this form of sequential data assimilation, see e.g. Jazwinsky (1970<ref>Jazwinsky A. H. (1970).''Stochastic Processes and Filtering Theory''. Academic Press.</ref>), Gelb (1974<ref>Gelb, A. 1974. Applied Optimal Estimation. Cambridge, Massachusetts: The MIT Press.</ref>) or Maybeck (1979<ref name="mayb">Maybeck, P.S. 1979.Stochastic Models, Estimation, and Control. Volume 141-1 of ''Mathematics in Science and Engineering''. London: Academic Press, Inc. Ltd.<br />
</ref>) for the theoretical background. This approach resembles optimal interpolation, except that it explicitly treats uncertainties in the numerical model dynamics, as well as in the observations and computes the solution error covariances as the model propagates forward in time, rather than assuming that they are known a priori. Originally the Kalman Filter was designed for linear systems. For non-linear systems the algorithm must appropriately be adapted or approximated, e.g. by a repeated linearisation of the model at its current state leading to the Extended Kalman Filter (see e.g. Maybeck, 1979<ref name="mayb"/>). For applications in tidal flow models with emphasis on storm surge forecasting, see Heemink and Kloosterhuis (1990<ref>Heemink, A.W., Kloosterhuis, H. 1990. Data assimilation for non-linear tidal models. ''International Journal for Numerical Methods in Fluids'' 11(12): 1097-1112.</ref>) or Heemink et al. (1997<ref name="heem">Heemink, A.W., Bolding, K., Verlaan, M. 1997. Storm surge forecasting using Kalman Filtering. ''Journal Meteorological Society Japn'', 75(1B): 305-318.</ref>). Recently new algorithms have been developed that do not require or use a model dependent implementation in the form of a tangent linear model. Important examples include the Ensemble Kalman Filter (EnKF) introduced by Evensen (1994<ref>Evensen, G. (1994), Sequential data assimilation with a non-linear quasi-geostrophic model using Monte Carlo methods to forecast error statistics, ''J. Geophys. Res.'', 97(17), 905-924.</ref>; 1997<ref>Evensen G. (1997). “Advanced Data Assimilation for strongly non-linear dynamics,” ''Monthly weather review'', 125(6), pp. 1342-1345.</ref>; 2003<ref>Evensen, G. (2003).The Ensemble Kalman Filter: theoretical formulation and practical implementation. ''Ocean Dynamics'', 53, 343 – 367.</ref>), and so called reduced-rank approaches (Heemink et al., 1997<ref name="heem"/>; Verlaan and Heemink, 1997<ref>Verlaan, M., Heemink, A.W., 1997. Tidal flow forecasting using reduced-rank square root filters. ''Stochastic Hydrology and Hydraulics'', 11(5): 349-368.</ref>). Heemink et al. (2001<ref>Heemink, A.W., Verlaan, M., Segers, A.J. 2001. Variance Reduced Ensemble Kalman Filtering. ''Monthly Weather Review'', 129: 1718-1728.</ref>) propose to combine such algorithms. Numerically these generic filter algorithms tend to be more robust for non-linearities in the model than the conventional model dependent approaches such as EKF. Therefore EnKF and reduced rank algorithms may in particular be suited for data assimilation in highly non-linear models. Recent examples of applications in surface hydrology and coastal hydrodynamics are given by El Serafy et al., 2005<ref>El Serafy, G.Y., Gerritsen H., Mynett, A.E. and Tanaka M.(2005), “Improvement of stratified flow forecasts in the Osaka Bay using the steady state Kalman filter”, ''Proc. 31st IAHR Congress'', Seoul, Eds. Byong-Ho Jun, Sang-Il Lee, Il Won Seo, Gye-Woon Choi, 795-804. </ref>; El Serafy and Mynett, 2004<ref>El Serafy, G.Y. and Mynett, A.E. (2004). Comparison of EKF and EnKF in SOBEK RIVER:Case study Maxau – IJssel, Proc. ''6th Int. Conf. on HydroInformatics'', Eds. Liong, Phoon & Babovic. World Scientific Publishing Company, ISBN 981-238-787-0,513-520.</ref>; Weerts and El Serafy, 2006<ref name="weer">Weerts, A. and G. Y. El Serafy, 2006. Particle Filtering and Ensemble Kalman Filtering for runoff nowcasting using conceptual rainfall runoff models, ''Water Resources Research'', Vol. 42, No. 9, W09403, doi:10.1029/2005WR004093.</ref>. Other simplified or related methods are the so-called particle filters, e.g. the Residual Resampling Filter (Isard and Blake, 1998<ref>Isard M. and Blake A. (1998), CONDENSATION -- conditional density propagation for visual tracking, ''Int. J. Computer Vision'', 29, 1, 5-28.</ref>; El Serafy and Weerts, 2006<ref name="weer"/>).<br />
<br />
===Combination with data driven modelling techniques===<br />
While filtering techniques have so far been practically applied for conceptual dynamic models, they also provide important new opportunities for combination with data driven models. Given the computational efficiency of data driven models, their combination with on-line sequential data assimilation facilities has a promising potential for operational and real time modelling and forecasting. For hydrology, real time flood forecasting, prediction of water loads in drainage systems, forecasting and control of hydraulic structures such as sluices, weirs or barriers, can be mentioned as relevant applications. For a further discussion on data assimilation in dynamic neural networks, see (Van den Boogaard et al., 2000<ref>Van den Boogaard, H.F.P., Ten Brummelhuis, P.G.J. Mynett, A.E. 2000. On-Line Data Assimilation in Auto-Regressive Neural Networks. ''Hydroinformatics 2000 Conference'', The University of Engineering, IOWA City, USA, July 23-27, 2000.</ref>; Van den Boogaard and Mynett, 2004<ref>Van den Boogaard, H.F.P. and A.E. Mynett, 2004. Dynamic neural networks with data assimilation. ''Hydrological Processes'', 18, 1959-1966.</ref>).<br />
<br />
==See also==<br />
Good examples of the application of data assimilation techniques can be found in:<br />
* [http://www.ecmwf.int/ Weather forecasts]<br />
* [http://www.rws.nl/themas/water/meetsystemen_watergegevens/index.aspx Water level forecasts (in Dutch)]<br />
* [http://www.hmc-noordzee.nl/ Hydro Meteo Centre North Sea (in Dutch)]<br />
<br />
==References==<br />
<references/><br />
<br />
<br />
{{authors <br />
|AuthorID1=16024<br />
|AuthorFullName1= Gerritsen, Herman<br />
|AuthorName1=Gerritsen, Herman<br />
|AuthorID2=16023 <br />
|AuthorFullName2= Boogaard, Henk van den<br />
|AuthorName2=Boogaard, Henk van den}}<br />
<br />
[[Category: Articles by Boogaard, Henk van den]]<br />
<br />
[[Category:Theme_9]]<br />
[[Category:Techniques and methods in coastal management]]<br />
[[Category:Evaluation and assessment in coastal management]]<br />
[[Category:Coastal and marine information and knowledge management]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Eutrophication_in_coastal_environments&diff=30651
Eutrophication in coastal environments
2009-07-09T13:39:46Z
<p>Wouter Kreiken: featured</p>
<hr />
<div>{{featured}}<br />
<br />
'''[[Eutrophication]]''' is the enrichment of water as a result of an increase in [[nutrient]]s, which can have a negative impact on the marine and coastal environment. The negative effects of [[eutrophication]] on marine [[ecosystem]]s includes: [[algal bloom]]s, increased growth of macroalgae, increased sedimentation and oxygen consumption, oxygen depletion in the bottom water and sometimes the death of [[benthic]] animals and fish. Coastal European areas in particular the Baltic Sea provides an indication as to the negative affects that [[eutrophication]] can have including: the presence of blue-green algae which is potentially harmful to humans as well as the presence of large mats of drifting algae that get deposited along the shorelines and decay. In order to reduce the negative effects of [[eutrophication]] [[nutrient]] inputs need to be reduced and an integrated management strategy needs to be employed. <br />
<br />
==Eutrophication in coastal environments==<br />
<br />
[[Eutrophication]] involves the enrichment of water by excess [[nutrient]]s. It can cause serious problems in the coastal zone through disturbance of ecological balances and fisheries, and through interference with recreational activities and quality of life. [[Eutrophication]] is the result of an [[anthropogenic|anthropogenically]] induced alteration of the global nitrogen cycle, and just like [[climate change]], should be regarded as a "global change". [[Eutrophication]] is usually treated scientifically and in terms of management as a local and regional phenomenon. Coastal regions throughout the world and Europe are affected by [[eutrophication]].<br />
<br />
==What is eutrophication about?==<br />
[[image:Baltic.jpg|thumb|right|Fig. 1. Cyanobacteria bloom, Western Baltic, 1997]]<br />
*It’s about '''increased productivity''' (conversion of light and carbon dioxide into living organic matter – a process that is limited by ''[[nitrogen]]'' and/or ''[[phosphorus]]'') and unacceptable ecological effects as [[algal bloom]]s and oxygen depletion, kills off benthic animals and fish<br />
*It’s caused by '''increased inputs''' of [[nutrient]]s from point sources, activities in the upstream catchment (''e.g.'' losses from agriculture) and atmospheric deposition.<br />
<br />
<br />
<br />
===What are we really talking about?===<br />
;[[Eutrophication]] : “eu” = “well” or “good”<br />
:“trope” = “nourishment”[[image:German Bight.jpg|thumb|right|Fig. 2. Noctiluca milaris bloom, German Bight, 2000]]<br />
<br />
But is “''[[eutrophication]]''” good?<br />
*In general: NO … it is actually ”bad” …<br />
*Too many [[nutrient]]s in the wrong places may cause problems and result in changes in structure, function and stability of the marine [[ecosystem]]s.<br />
<br />
*[[Eutrophication]] is ”too much of a good thing”<br />
<br />
==Effects of Eutrophication==<br />
The different processes and effects of coastal [[eutrophication]] are well documented<ref>Cloern, J. (2001) Our evolving conceptual model of the coastal eutrophication problem. Mar. Ecol. Prog. Ser., 210, 223–253.[ISI]</ref> <ref>Conley, D. J., Markager, S., Andersen, J. et al. (2002) Coastal eutrophication and the Danish National Aquatic Monitoring and Assessment Program. Estuaries, 25, 706–719.[Medline]</ref> <ref>Rönnberg, C. and Bonsdorff, E. (2004) Baltic Sea eutrophication: area-specific ecological consequences. Hydrobiologia, 514, 227–241.[CrossRef][ISI]</ref> and it has been considered as one of the biggest threats to marine [[ecosystem]] health for decades<ref>Ryther and Dunstan, 1971</ref> <ref>Nixon, S. W. (1995) Coastal marine eutrophication: a definition, social causes, and future concerns. Ophelia, 41, 199–219.[ISI]</ref> <ref>Bachmann, R. W., Cloern, J. E., Heckey, R. E. et al. (eds) (2006) Eutrophication of freshwater and marine ecosystems. Limnol. Oceanogr., 51 (1, part 2), 351–800.</ref>. <br />
<br />
[[Image:eutrophicationflow.jpg|600px|thumb|centre|Fig. 3. Eutrophication flow diagram. Source: HELCOM, 2006 <ref name="HELCOM">HELCOM, (2006) Andersen, J (DHI) and Pawlak, J (MEC), Nutrients and Eutrophication in the Baltic Sea – Effects, Causes, Solutions. Baltic Sea Parliamentary Conference.[http://sea.helcom.fi/dps/docs/documents/Monitoring%20and%20Assessment%20Group%20(MONAS)/EUTRO-PRO/EUTRO-PRO%203,%202006/BSPC%20Nutrients%20and%20Eutrophication%20in%20the%20BS.pdf]</ref><br />
]]<br />
<br />
<br />
Effects of [[eutrophication]] on marine [[ecosystem]]s are well known<ref name="HELCOM"/>:<br />
*[[algal bloom]]s resulting in green water<br />
*reduced depth distribution of submerged aquatic vegetation<br />
*increased growth of nuisance macroalgae<br />
*increased sedimentation, increased oxygen consumption<br />
*oxygen depletion in bottom water, and <br />
*sometimes dead benthic animals and fish. <br />
<br />
<br />
[[image:koncept.jpg|500px|thumb|centre|Fig. 4. Eutrophication schematic. Source: HELCOM, 2006 <ref name="HELCOM"/>]]<br />
<br />
<br />
===General effects===<br />
Major effects of [[eutrophication]] include structure and function changes in the entire marine [[ecosystem]] and a reduction in stability. The following are responses to increased nutrient inputs<ref name="HELCOM"/>:<br />
#Corresponding increase in nutrient concentrations<br />
#Change in ratio between dissolved [[nitrogen]] and [[phosphorus]] in the water: ''DIN:DIP'' ratio. Optimal is 16:1 – called the ''[[Redfield ratio]]''. Significantly lower ratio causes potential [[nitrogen]] limitation; while a higher ratio leads to [[phosphorus]] limitation of [[phytoplankton]] [[primary production]]. <br />
<br />
<br />
''[[Primary production]]'' is usually limited by availability of light and nutrients.<br />
Nutrient enrichment increase [[phytoplankton]] [[primary production]], which increases biomass, which decreases light penetration through water column. Light penetration is measured by [[Secchi depth]] - a decreased [[Secchi depth]] can reduce colonization depth of macroalgae and [[seagrass]]es.<br />
<br />
<br />
Responses to nutrient enrichment ([[pelagic]] [[ecosystem]]s) involve a gradual change towards<ref name="HELCOM"/>:<br />
#Increased [[plankton|planktonic]] [[primary production]] compared to benthic production<br />
#Dominance of microbial food webs over linear [[plankton|planktonic]] food chains<br />
#Dominance of non-siliceous [[phytoplankton]] species over diatom species<br />
#Dominance of gelatinous [[zooplankton]] (jellyfish) over [[crustacea]]n [[zooplankton]]<br />
<br />
Finally, [[eutrophication]] issues<ref name="HELCOM"/> are often divided into three groups: <br />
#Causative factors: inputs, elevated nutrient concentrations, Redfield ratio changes<br />
#Direct effects: primary producers, namely ''[[phytoplankton]]'' and ''submerged aquatic vegetation''<br />
#Indirect effects (secondary effects): related to [[zooplankton]], fish and ínvertebrate benthic fauna (animals living on seafloor).<br />
<br />
===Primary and Secondary Effects===<br />
Some important primary and secondary effects are discussed in the sections below. <br />
<br />
====Phytoplankton====<br />
[[Phytoplankton]] are at base of pelagic food webs in aquatic systems, have generation times from less that a few days, respond rapidly to nutrient concentration changes, and are often quantified in terms of:<br />
#[[Primary production]]<br />
#Biomass (chlorophyll-a concentration, or carbon biomass)<br />
#Bloom frequency<br />
<br />
====Submerged aquatic vegetation==== <br />
Submerged aquatic vegetation are affected by [[eutrophication]] through<ref name="HELCOM"/>:<br />
#Reduced light penetration and shadowing effects from [[phytoplankton]] can reduce the depth distribution, biomass, composition and species diversity; and<br />
#increased growth of filamentous and short lived nuisance macroalgae at the cost of long lived species can lead to a change in structure of macroalgae communities with reduced diversity.<br />
Additionally,<br />
*[[Seagrass]] meadows and perennial macroalgae are important nursery areas for coastal fish populations. <br />
*Short-lived (annual) nuisance macroalgae are favoured by large nutrient inputs.<br />
<br />
====Oxygen depletion<ref name="HELCOM"/>====<br />
Oxygen depletion, or ''[[hypoxia]]'', is a common effect of [[eutrophication]] in bottom waters. This effect may be episodic, occuring annually (most common in summer/autumn), persistent, or periodic in the coastal zone.<br />
*Lethally low oxygen concentrations depend on the species. Fish and crustaceans have higher oxygen requirements; other speices have lower requirements. <br />
*[[hypoxia|Hypoxic]] and anoxic (no oxygen) conditions may results in formation and release of hydrogen sulphide (H<sub>2</sub>S), which is lethal to organisms. <br />
*Anoxic periods cause the release of phophorus from sediments - dissolved inorganic phosphorus (DIP), and ammonium is released under [[hypoxia|hypoxic]] conditions. DIP and ammonium in water column can enhance [[algal bloom]]s.<br />
*The predicted effect of global warming is to increase [[hypoxia]] with increased temperature. A 4 degree temperature increase is projected to results in a doubling of [[hypoxia]] in some parts of North Sea.<br />
*An example of the effect: Eelgrass responds to low oxygen concentrations, and dies off under these conditions (often in combination with high temperatures)<br />
<br />
====Invertebrate benthic fauna<ref name="HELCOM"/>====<br />
Invertebrate [[benthic]] fauna can cope with oxygen depletion to varying degrees (days – month). If O<sub>2</sub> drops below zero and H<sub>2</sub>S is released all organisms are killed immediately. Mobile [[benthic]] invertebrates in sediment move to surface when O<sub>2</sub> decreases - there are increased catches of fish and crustaceans during these times. It is difficult to predict when animals will return after [[eutrophication]] events. The area affected plays a factor: small areas are recolonised and re-established more quickly than larger areas.<br />
<br />
===Climate change===<br />
*Seas are important in element cycling – carbon and nitrogen cycle; phosphorus and silicate cycle<br />
*Ocean still takes up more carbon than it releases – depositing some in sediments<br />
<br />
==Solutions==<br />
Nutrient inputs must be reduced to levels that do not put at risk target values for mitigation of [[eutrophication]]. Integrated management strategies should enable characterization of all pressures on water bodies in order to develop a coherent approach to deal with the pressures in a cost effective manner<ref name="HELCOM"/>.<br />
<br />
==European Coastal Areas==<br />
Eutrophication is the result of an anthropogenically induced alteration of the global nitrogen cycle, and just like climate change, should be regarded as a "global change". Eutrophication is usually treated scientifically and for management as a local and regional phenomenon. Coastal regions throughout the world and Europe are affected by eutrophication.<br />
<br />
Within Europe, regional seas such as the Baltic and Mediterranean Seas are currently adversely affected by eutrophication, with climate change expected to intensify these adverse impacts. As well as monitoring fresh water impacts on coastal areas, it will be important to monitor impacts between seas such as the Mediterranean and Black Seas. For example, the Black Sea is strongly eutrophic, and enters the Mediterranean Sea at the North Aegean near the borders of Greece and Turkey.<br />
<br />
More global approaches were considered in meetings such as the International Symposium on Research and Management of Eutrophication in Coastal Ecosystems from June 20 to 23, 2006 in Nyborg, Denmark. This meeting included a keynote speaker, a working seminar, produced some outcomes,and led to the creation of an European group to address the issue of climate change and eutrophication. <br />
<br />
The main source of nitrogen to European coastal waters is agricultural runoff discharged into the sea via rivers, identified as originating from sources of ammonia evaporation in animal husbandry and partly from fossil fuel combustion in traffic, industry and households<ref name="ECW">Ærtebjerg, G. et al., Eutrophication in Europe’s Coastal Waters. Topic Report No 7/2001. European Environment Agency. [http://reports.eea.europa.eu/topic_report_2001_7/en]</ref>. For phosphorus the major sources are treated and untreated discharges to the sea from households and industry as well as soil erosion<ref name="ECW"/>.<br />
<br />
Within Europe, regional seas such as the Baltic and Mediterranean Seas are currently adversely affected by [[eutrophication]], with [[climate change]] expected to intensify these adverse impacts. As well as monitoring fresh water impacts on coastal areas, it will be important to monitor impacts between seas such as the Mediterranean and Black Seas. For example, the Black Sea is strongly eutrophic, and enters the Mediterranean Sea at the North Aegean near the borders of Greece and Turkey.<br />
<br />
[[Eutrophication]] seriously affects the Baltic sea marine environment, resulting in [[algal bloom]]s, reduced water clarity, oxygen reduction and death of bottom animals. The causes behind this are well known<ref name="HELCOM"/>: discharges, losses and emissions of nitrogen and phosphorus to the aquatic environment. Reductions of discharges from municipal wastewater treatment plants and industries have been the focus for many years as have losses and emissions of nitrogen compounds from agriculture and traffic.<br />
<br />
More global approaches were considered in meetings such as the [http://eutro2006.dhi.dk/ International Symposium on Research and Management of Eutrophication in Coastal Ecosystems] from June 20 to 23, 2006 in Nyborg, Denmark. This meeting included a keynote speaker, a working seminar, produced some outcomes,and led to the creation of an European group to address the issue of [[climate change]] and [[eutrophication]].<br />
<br />
====Causes in Baltic Sea====<br />
Human-mediated nutrient enrichment<ref name="HELCOM"/> in the Baltic Sea can be caused by input of nutrients in form of: <br />
#Direct inputs from point sources (sewage treatment plants, industries)<br />
#Atmospheric deposition<br />
#Riverine inputs (from activities in the catchment: eg point sources, agricultural losses, atmospheric deposition, natural background losses (natural erosion and leakage of nutrients from areas without much human activities) and stream, river and lake retention)<br />
<br />
'''Waterborne:''' Agriculture forestry, scattered dwellings, municipanlities, industries, natural background losses.<br />
<br />
'''Airborne:''' Nitrogen compounds emitted to atmosphere: <br />
*Nitrogen oxides: road transportation, energy combustion, shipping<br />
*Ammonia emissions: mostly from agriculture.<br />
*Distant sources<br />
<br />
'''The role of agriculture in nitrogen inputs:'''<br />
The main source of nitrogen inputs in Baltic Sea is agricultural discharge via rivers, deriving from:<br />
#Soil cultivation<br />
#Fertiliser use<br />
#Use of manure<br />
#Intensive and uncontrolled agriculture<br />
<br />
====Aspects of Eutrophication problem in the Baltic sea<ref name="HELCOM"/>====<br />
*Excessive [[phytoplankton]] blooms are a major problem – especially of blue-green algae. There are commonly summertime [[algal bloom]]s in most parts of Gulf of Finland, Gulf of Riga, the Baltic Proper and south-western parts of Baltic Sea<br />
Problems caused:<br />
*bathing people can hardly see their feet<br />
*blue-green [[ALGADEC - Detection of toxic algae with a semi-automated nucleic acid biosensor|algae potentially toxic]] to humans and animals<br />
*large mats of drifting algae deposited along shores and decay<br />
<br />
====Baltic Sea Solutions====<br />
The following steps have been suggested<ref name="HELCOM"/><br />
#Establish overall goals and target values<br />
#Implement relevant measures directly linked to fulfillment of these overall goals and targets<br />
#Carry out monitoring<br />
#Conduct assessments<br />
#Evaluate whether the goals and targets have been fulfilled or not<br />
<br />
'''Main drivers:''' <br />
*European Directives (see links below)<br />
*Decisions and recommendations adopted by [http://www.helcom.fi HELCOM]<br />
*National action plans<br />
<br />
==EU Directives:==<br />
:[http://ec.europa.eu/environment/water/water-urbanwaste/directiv.html EC Urban Waster Water Treatment Directive]<br />
:[http://ec.europa.eu/environment/water/water-nitrates/directiv.html EC Nitrates Directive]<br />
:[http://ec.europa.eu/environment/water/water-framework/index_en.html EU Water Framework Directive]<br />
:[http://ec.europa.eu/environment/water/marine.htm Marine Strategy Directive]<br />
<br />
==See also==<br />
:[[Theme 4]] - Pollution<br />
:[[Water quality/pollution]]<br />
<br />
==External links==<br />
:[http://www.BSPC.net Baltic Sea Parlimentary Conference ]<br />
:[http://www.bernet.org/wm125051 BERNET:] Baltic Eutrophication Regional Network <br />
:[http://www.BONUSportal.org BONUS] for the future of the Baltic Sea<br />
:[http://www.EEA.europa.eu European Environment Agency ]<br />
:[http://www.HELCOM.fi HELCOM ]<br />
:HELCOM Indicator fact sheets: <br />
::[http://www.helcom.fi/environment2/ifs/ifs2005/en_GB/inflow water exchange]<br />
::[http://www.helcom.fi/environment2/ifs/ifs2005/en_GB/winternutriets winter nutrient concentrations] <br />
::[http://www.helcom.fi/environment2/ifs/ifs2005/en_GB/transparency water clarity] <br />
::[http://www.helcom.fi/environment2/ifs/ifs2005/en_GB/blooms algal blooms]<br />
::[http://www.helcom.fi/environment2/ifs/ifs2005/Chlorophyll-a/en_GB/chlorophyll chlorophyll-a concentrations]<br />
::[http://www.helcom.fi/environment2/ifs/ifs2005/en_GB/oxygen_deepbasins hydrography and oxygen in the deep basins]<br />
:[http://www.MARE.su.se MARE] Research program on Baltic Sea environmental issues <br />
:[http://www.dmu.dk/International/Water/ National Environment Research Institute (DK) Aquatic page]<br />
:[http://www2.dmu.dk/1_Viden/2_Miljoe-tilstand/3_vand/4_eutrophication/definition.htm Nutrients and Eutrophication in Danish Marine Waters]<br />
:[http://www.OSPAR.org OSPAR] For the protection of the marine environment of the north-east Atlantic<br />
:[http://www.waterforecast.com/defaultUK.asp The Water Forecast]<br />
:Wikipedia: [http://en.wikipedia.org/wiki/Eutrophication Eutrophication article]<br />
:[http://www.panda.org/about_wwf/where_we_work/europe/what_we_do/baltics/our_work/index.cfm WWF Baltic Ecoregion Programme]<br />
<br />
==References==<br />
:[http://sea.helcom.fi/dps/docs/documents/Monitoring%20and%20Assessment%20Group%20(MONAS)/EUTRO-PRO/EUTRO-PRO%203,%202006/BSPC%20Nutrients%20and%20Eutrophication%20in%20the%20BS.pdf Nutrients and Eutrophication in the Baltic Sea - Effects, Causes, Solutions] (HELCOM) - main reference for this article<br />
<br />
<references/><br />
<br />
==Further Reading==<br />
The Biology and Ecology of Seagrasses (ed. Brant W. Touchette), 2007. Journal of Experimental Marine Biology and Ecology, Volume 350, Issues 1-2, Pages 1-260 (9 November 2007), . http://www.sciencedirect.com/science/journal/00220981<br />
<br />
<br />
{{author<br />
|AuthorID=13036<br />
|AuthorFullName=Caitlin Pilkington<br />
|AuthorName=CaitlinPilkington}}<br />
<br />
<br />
<br />
[[category:Theme 6]]<br />
[[category:Baltic]]<br />
[[category:Black sea]]<br />
[[category:Mediterranean]]<br />
[[category:Atmospheric processes, air and climate]]<br />
[[category:Biological processes and organisms]]<br />
[[category:Ecological processes and ecosystems]]<br />
[[category:Land and ocean interactions]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Effects_of_global_climate_change_on_European_marine_biodiversity&diff=30650
Effects of global climate change on European marine biodiversity
2009-07-09T13:38:58Z
<p>Wouter Kreiken: {{featured}}</p>
<hr />
<div>{{featured}}<br />
<br />
This article discusses global warming and the range of effects on marine systems. <br />
The effects may be related to changing water temperatures, changing water circulation or changing habitat; as a consequence of these changes, altered pathways within biogeochemical cycles and food webs are detected as well. In the first case, the biological responses and impacts result from the physical effects.<ref name="Phillipart"> Phillipart C.J.M. (ed.) (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach.'' European Science Foundation, Marine Board: Strasbourg, France.'' 82pp.</ref><br />
<br />
Even without human-induced climate change, [[Natural variability in Coastal Ecosystems|the biodiversity and biogeography of species is continuously changing]] (seasonal and yearly changes). Consequently, long term monitoring is necessary in order to evaluate these processes. The marine systems however may become more dynamic and variable due to climate change.<ref name="Phillipart"> Phillipart C.J.M. (ed.) (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach.'' European Science Foundation, Marine Board: Strasbourg, France.'' 82pp.</ref><br />
<br />
Europe may be less threatened by sea-level rise than many developing country regions. However, coastal ecosystems do appear to be threatened, especially enclosed seas such as the Baltic, the Mediterranean and the Black Sea. These seas have only small and primarily east-west orientated movement corridors, which may restrict northward displacement of organisms in these areas.<ref name="Nicholls"> Nicholls, R.J.; Klein,R.J.T. (2005). Climate change and coastal management on Europe's coast, '''in''': Vermaat, J.E. ''et al.'' (Ed.) (2005). Managing European coasts: past, present and future. pp. 199-226.</ref><br />
<br />
Discussion of the impact on [[estuaries]] in transitional waters and the introduction of the concept of '[[coastal squeeze]]' covered in the original version of the article have been moved to two new articles.<br />
<br />
<br />
==Effects on primary production==<br />
<br />
Higher temperatures and enhanced [[stratification]] could affect the productivity of [[phytoplankton]]. A number of models predict an increase in global [[Primary production|primary production]] of between 1% and 8% by 2050, when compared to pre-industrial times.<ref name="Sarmiento"> Sarmiento, J.L.; Slater, R.; Barber, R.; Bopp, L.; Doney, S.C.; Hirst, A.C., Kleypas, J.; Matear, R.; Mikolajewicz, U.; Monfray, P.; Soldatov, V.; Spall, S.A.; Stouffer, R. (2004). Response of ocean ecosystems to climate warming. ''Glob Biogeoch Cycles'' 18,3. '''cit. in''': Philippart, C.J.M. (Ed.). (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach. ''ESF Marine Board Position Paper''. European Science Foundation, Marine Board: Strasbourg, France. 82 pp.</ref> <br />
<br />
Because phytoplankton is an important basis of the marine food web, any change in the timing, abundance or species composition of the phytoplankton will have an effect on the whole food web.<ref name="Phillipart"> Phillipart C.J.M. (ed.) (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach.'' European Science Foundation, Marine Board: Strasbourg, France.'' 82pp.</ref><br />
<br />
==Effects on the recruitment process==<br />
<br />
The population dynamics of a lot of marine vertebrates and fish are driven by recruitment processes. The [[recruitment]] of cold temperate species is often synchronized with seasonal production cycles of phytoplankton. Increasing sea water temperatures may advance the timing of reproduction of these fish species; this may result in a mismatch with their food source (phytoplankton) (match/mismatch hypothesis). A change in recruitment success will lead to shifts in species composition.<ref name="Phillipart"> Phillipart C.J.M. (ed.) (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach.'' European Science Foundation, Marine Board: Strasbourg, France.'' 82pp.</ref><br />
<br />
===Example: cod recruitment in the North Sea===<br />
<br />
<br />
The Atlantic cod (''Gadus morhua'') recruitment in the North Sea, in the past 40 years, was influenced by changes at the base of the food web (bottom-up-control), induced by the rise of temperature. Cod recruitment decreased from the mid-1980s, coincident with unfavorable changes in the plankton ecosystem.<ref name="Beaugrand"> Beaugrand, G.; Brander, K.M.; Lindley, J.A.; Souissi, S.; Reid, P.C. (2003). Plankton effect on cod recruitment in the North Sea.''Nature (Lond.) 426(6967)'': 661-664.</ref><br />
[[Image:Atlantic cod.jpg|right|300px|Atlantic cod ''Gadus morhua'' SOURCE: www.fishbase.org |frame]]<br />
[[Image:cod recruitment.jpg|centre|300px|Long-term changes (1958-1999) in the plankton index (in black), and long-term changes (1959-2000) in cod recruitment (in red, decimal logarithm).(Biological parameters for the diet and growth of cod larvae and juveniles: total calanoid copepods (qualitative indicator of food for larval cod), the mean size of calanoid copepods (qualitative indicator of food) and the abundance of two dominant congeneric species (Calanus finmarchicus and C. helgolandicus). Reprinted by permission from Macmillan Publishers Ltd: [NATURE] (Beaugrand, G.; Brander, K.M.; Lindley, J.A.; Souissi, S.; Reid, P.C. (2003). Plankton effect on cod recruitment in the North Sea. ''Nature (Lond.) 426(6967''): 661-664.), copyright (2003)|frame]]<br />
<br />
<br />
==Effects on the [[biogeography]]== <br />
<br />
The species movement in a warming area is towards the poles in general. Since global warming accelerated in the late 1980s, pole ward advances of southern species and retreats of northern species have been recorded in [[zooplankton]], fish and benthic species.<ref name="Brander"> Brander, K.; Blom, G.; Borges, M.F.; Erzini, K.; Henderson, G.; MacKenszie, B.R.; Mendes, H.; Ribeiro, J.; Santos, A.M.P.; Toresen, T. (2003). Changes in fish distribution in the eastern North Atlantic: Are we seeing a coherent response to changing temperature? ''ICES Mar Sci Symp'' 219: 261-270. '''cit. in''': Philippart, C.J.M. (Ed.). (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach. ''ESF Marine Board Position Paper''. European Science Foundation, Marine Board: Strasbourg, France. 82 pp.</ref> .<ref name="Southward2005"> Southward, A.J.; Langmead, O.; Hardman-Mountford, N.J.; Aiken, J.; Boalch, G.T.; Dando, P.R.; Genner, M.J.; Joint, I.; Kendall, M; Halliday, N.C.; Harris, R.P.; Leaper, R.; Mieszkowska, N.; Pingree, R.D.; Richardson, A.J.; Sims, D.W.; Smith, T.; Walne, A.W.; Hawkins, S.J. (2005). Long term oceanographic and ecological research in the western English Channel. ''Adv Mar Biol'' 47: 1-105 '''cit. in''': Philippart, C.J.M. (Ed.). (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach. ''ESF Marine Board Position Paper''. European Science Foundation, Marine Board: Strasbourg, France. 82 pp.</ref> <br />
<br />
The species distribution is not always northwards. For example when the stock of the main prey of the harp seals in the Barents Sea collapsed, these seals migrated southwards along the coast of Norway and into the North Sea in search of food.<ref name="Phillipart"> Phillipart C.J.M. (ed.) (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach.'' European Science Foundation, Marine Board: Strasbourg, France.'' 82pp.</ref><br />
<br />
===Example: Study of barnacles in the Celtic-Biscay shelf===<br />
[[Image:barnacles.jpg|right|300px|Long-term changes in ''Semibalanus balanoides'' and ''Chthamalus'' spp. for several shores at different submersion levels (HWN: High Water Neap; MTL: Mean Tidal Low; LWN: Low Water Neap) on the south coast of Devon and Cornwall. SOURCE: © Southward 1995<ref name="Southward1995"> Southward, A.J.; Hawkins, S.J.; Burrowa, M.T. (1995). Seventy years` observations of changes in distribution and abundance of zooplankton and intertidal organisms in the western English Channel in relation to rising sea temperature. J'' Therm Biol'' 20: 127-155. '''cit. in''': Philippart, C.J.M. (Ed.). (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach. ''ESF Marine Board Position Paper''. European Science Foundation, Marine Board: Strasbourg, France. 82 pp.</ref>|frame]]<br />
The Celtic-Biscay shelf was liable to warming in the 1930; in the 1960 there was a switch back to colder. Changes in species assemblages were described on rocky shores, using barnacles as a sensitive indicator of wider changes in marine life.<ref name="Southward1995"> .Southward, A.J.; Hawkins, S.J.; Burrowa, M.T. (1995). Seventy years` observations of changes in distribution and abundance of zooplankton and intertidal organisms in the western English Channel in relation to rising sea temperature. J'' Therm Biol'' 20: 127-155. '''cit. in''': Philippart, C.J.M. (Ed.). (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach. ''ESF Marine Board Position Paper''. European Science Foundation, Marine Board: Strasbourg, France. 82 pp.</ref> <ref name="Southward2005"> Southward, A.J.; Langmead, O.; Hardman-Mountford, N.J.; Aiken, J.; Boalch, G.T.; Dando, P.R.; Genner, M.J.; Joint, I.; Kendall, M; Halliday, N.C.; Harris, R.P.; Leaper, R.; Mieszkowska, N.; Pingree, R.D.; Richardson, A.J.; Sims, D.W.; Smith, T.; Walne, A.W.; Hawkins, S.J. (2005). Long term oceanographic and ecological research in the western English Channel. ''Adv Mar Biol'' 47: 1-105 '''in''': Philippart, C.J.M. (Ed.). (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach. ''ESF Marine Board Position Paper''. European Science Foundation, Marine Board: Strasbourg, France. 82 pp.</ref> These showed switches between warm water barnacles in the 1950s (''Chthamalus'' spp.) to greater dominance by the cold water barnacle ''Semibalanus balanoides'' in the 1960s and 1970s. On rocky shores warm water barnacles now exceed the levels found in the 1950s.<ref name="Phillipart"> Phillipart C.J.M. (ed.) (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach.'' European Science Foundation, Marine Board: Strasbourg, France.'' 82pp.</ref> <br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
==Effects on the phenological relationships and community structure==<br />
<br />
The response to climate changes differs between the species, inducing a decoupling of [[Phenology|phenological]] relationships (relative timing of life cycle events). The decoupling may affect the community structure and food webs by altering the interactions between a species and its competitors, mutualists, predators, prey or pathogens. <br />
For example, in the case of seabirds, chick diet composition during development is likely to be an important mechanistic link between climate variability and the observed decline in seabird populations.<ref name="Kitaysky"> Kitaysky, A.S.; Kitaiskaia, E.V.; Piatt, J.F.; Wingfield, J.C. (2005). A mechanistic link between chick diet and decline in seabirds? ''Proc Biol Sci Proc R Soc B'' 273:445-450. '''cit. in''': Phillipart C.J.M. (ed.) (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach.''ESF Marine Board Position Paper''. European Science Foundation, Marine Board: Strasbourg, France. 82 pp.</ref><br />
<br />
A study in Kongsfjorden (79 °N) concluded that changing temperatures have a direct and very immediate influence on the species composition of plankton as well as on the biodiversity. The response of benthic organisms to rising temperature is slower and less drastic compared with planktonic organisms. Planktonic organisms may be a better indicator of global warming-driven changes than the benthic organisms. However benthic fauna is a good indicator of slow changes, especially when observed over a long period of time.<ref name="Kedra"> Kedra, M.; Walkusz, W. (2006). Global warming-driven biodiversity change: pelagic versus benthic domain [Arctic 79°N case study]'' MarBEF Newsletter'' 5: 23-24.</ref><br />
<br />
==Effects on the establishment of invasive species==<br />
[[Image:Crassostrea gigas.jpg|right|300px| Pacific oyster ''Crassostrea gigas'' SOURCE: www.spirula.nl|frame]]<br />
<br />
The establishment of non-indigenous species can be accelerated by rapid warming. For example, the recent warming has accelerated the adaptation of the Pacific oyster (''Crassostrea gigas'') on the local circumstances in the Netherlands and the UK.<ref name="Essink"> Essink, K.; Dettmann, C.; Farke, H.; Laursen, K.; LuerBen, G.; Marencic, H.; Wiersinga, W. (Eds). Wadden Sea Quality Status Report 2004. ''Wadden Sea Ecosystems'' 19-2005, 155-161pp. '''cit. in''': Phillipart C.J.M. (ed.) (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach.''ESF Marine Board Position Paper''. European Science Foundation, Marine Board: Strasbourg, France. 82 pp.</ref><br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
==Effects on biogeochemical cycles==<br />
<br />
In the past 200 years the oceans have absorbed approximately half of the CO<sub>2</sub> produced by fossil fuel burning and cement production. Calculations indicate that this uptake of CO<sub>2</sub> has led to a reduction of the pH of surface seawater ([[Acidification|acidification]]) of 0.1 units; this is an equivalent to a 30% increase in the concentration of hydrogen ions. If the CO<sub>2</sub> emissions from human activities rise on current trends then the average pH of the oceans could fall by 0.5 units by the year 2100.<br />
<br />
This fall in pH may have a huge impact on marine organisms, in particular to calcifying organisms such as most mollusks, corals, echinoderms, foraminifera and calcareous algae. Seawater has to be supersaturated with [[calcium]] and [[carbonate ions]] to ensure that once the biogenic calcareous structures are formed, it does not dissolve. Lower pH reduces the carbonate saturation of the seawater, making calcification harder.<br />
<br />
There is also a difference in vulnerability between the groups of organisms: corals and a group of mollusks ([[Pteropods|pteropods]]) precipitate aragonite; [[Coccolithophorids|coccolithophores]] and [[Foraminifera|foraminifers]] produce the less soluble calcite. Furthermore differs the function (e.g. metabolic or structural function) from the carbonate between the different groups and this is coupled to the sensitivity for acidification. It is likely as CO<sub>2</sub> levels increases, changes of species composition will occur because of the different responses of the species. An altered species composition may have a huge effect on the global carbon cycle.<ref name="Orr"> Orr, J.C.; Fabry, V.J.; Aumont, O.; Bopp, L.; Doney, S.C.; Feely, R.A.; Gnanadesikan, A.; Gruber, N.; Ishida, A.; Joos, F.; Key, R.M.; Lindsay, K.; Maier-Reimer, E.; Matear, R.J.; Monfray, P.; Mouchet, A.; Najjar, R.; Plattner, G.-K.; Rodgers, K.B.; Sabine, C.L.; Sarmiento, J.L.; Schlitzer, R.; Slater, R.D.; Totterdell, I.J.; Weirig, M.-F.; Yamanaka, Y.; Yool, A. (2005). Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms.'' Nature (Lond.) 437(7059) '': 681-686.</ref><br />
<br />
<br />
==Effects at the level of physiological responses to temperature rise==<br />
<br />
Temperature rise for the oceans as a whole is likely to be about 1 to 2 °C, in the next decades. Exceptions are semi enclosed marine lagoons and shallow bays that may mirror the atmospheric temperature rise as well. Additional, most aquatic sandy-shore animals are adapted to rapid changes in temperature and they seldom experience temperatures close to their upper tolerance limits. Further, sandy-beach animals are capable of burrowing and of escaping below the sand if conditions at the surface become hostile. <ref name="McLachlan"> McLachlan, A.; Brown, A.C. (2006). The ecology of sandy shores. 2nd. Edition. Academic Press: Amsterdam, The Netherlands. 373 pp.</ref><br />
This is in contrast to sessile organisms such as corals and mangroves that are unable to keep up with the higher temperature level.<br />
<br />
== See also ==<br />
The mediterranean sea: its biodiversity and the impact of global warming [http://www.marbef.org/outreach/newsletter.php]<p><br />
Climate exacerbates eutrophication in the North Sea [http://www.marbef.org/outreach/newsletter.php]<p><br />
<br />
==References==<br />
<br />
<references/><br />
<br />
[[Category:Marine habitats and ecosystems]]<br />
[[Category:climate change and global warming]]<br />
[[Category:Theme 7]]<br />
<br />
{{author<br />
|AuthorID=15336<br />
|AuthorFullName=Therry, Lieven<br />
|AuthorName=Ltherry}}</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Coastal_Hydrodynamics_And_Transport_Processes&diff=30649
Coastal Hydrodynamics And Transport Processes
2009-07-09T13:18:14Z
<p>Wouter Kreiken: {{featured}}</p>
<hr />
<div>{{featured}}<br />
<br />
The hydrodynamic conditions or processes, that come about from [[Tidal wave|waves]] transforming over a coastal profile and generating wave set up and [[Longshore current|longshore currents]], will result in movement and transport of the sediments (e.g. sand) present in the profile. This is referred to as ''littoral transport processes'' and is the main subject of this article. However, transport of fine sediments will also be discussed, but only very briefly.<br />
<br />
==Sediment transport in general==<br />
The sediment on the seabed is transported when it is exposed to large enough forces, or ''shear stresses'', by the water movements. These movements can be caused by the current or by the wave orbital velocities or a combination of both, the latter being the most important situation. The relevant parameters for the description of the sediment transport along a shoreline or in a coastal area are therefore the following:<br />
<br />
*The wave conditions at the site and the possible variations over the site plus the adjoining areas<br />
*The current conditions as well as the variations of these over the area <br />
*The water-level conditions, i.e. tide, storm surge and wave set-up<br />
*The [[bathymetry]] (the depth variations) in the area <br />
*The [[sediment]] characteristics over the area <br />
*The sources and sinks of sediment, such as rivers, eroding coasts or tidal inlets<br />
<br />
<br />
<ref name="Aagard">Written by Aagard, Troels. 2007.</ref>The link between hydrodynamic forcing and the morphological response of the beach is realized through the transport of sediment. This transport may occur as either [[bedload]] or as suspended load. Even though modelling efforts suggest that suspended load is the more important within the surf zone, particularly under high energy conditions, there is still no consensus on the subject, partly because [[bedload]] is very difficult to measure under field conditions. <br />
<br />
<ref name="Aagard"/>While suspended sediment transport may be easier to measure then [[bedload]] it is not a simple matter to predict, one of the main reasons being that the velocity field in the [[nearshore]] zone is oscillatory and that sediment resuspension (and transport) responds non-linearly to the forcing; further the existence of [[bedforms]] may induce phase changes between velocity and sediment concentration. <br />
<br />
<ref name="Aagard"/>Sediment concentrations within the surf zone have been found to depend upon elevation above the bed, bed configuration and local bed shear stress as well as wave breaker type. Sediment is mainly resuspended by the large shear stresses generated by wave motions while mean currents play a subordinate role. The reason is that in the [[nearshore]] region, oscillatory velocities are generally significantly larger than mean current velocities and the wave boundary layer thickness is small (resulting in steep velocity gradients) compared to the thickness of the current boundary layer. <br />
<br />
<ref name="Aagard"/>Physically, sediment can be resuspended from the seabed in a number of ways. Close to the bed, small turbulent eddies created by bed friction mobilize the sediment which can be mixed to higher elevations by turbulence generated by breaking waves. Hence, sediment concentration profile gradients are different under breaking and non-breaking waves. In the latter case, suspended sediment is confined to a relatively thin layer near the bed. <br />
<br />
<ref name="Aagard"/>The distribution of sediment in the water column may occur either as a diffusive process which generally occurs when the bed is flat and devoid of [[bedforms]], or as a convective process whereby sediment is suspended and lifted upward in coherent packages e.g. due to vortex shedding from ripples at the bed. In both cases, the vertical distribution of sediment in the water column can be approximated by:<br />
<br />
<br />
<br />
:<math>w_{s}c+\varepsilon_{s}(\delta_{c}/\delta_{z})= 0</math> <br />
<br />
<br />
where <math>w_{s}</math> is the fall velocity of the sediment, c is the sediment concentration, z is elevation above the bed and <math>\varepsilon_{s}</math> is an eddy diffusion coefficient representing the scale of turbulent mixing. This equation predicts that in a steady state situation, the downward flux of sediment (<math>w_{s}c</math>) must be balanced by an upward flux given by the product of the concentration gradient and the sediment diffusion.<br />
<br />
==Littoral Transport==<br />
[[Image:Littoral_b.jpg|thumb|400px|Fig. 1. Variation in littoral transport with wave exposure and wave incidence angle]]''Littoral transport'' is the term used for the transport of non-cohesive sediments, i.e. mainly sand, in the littoral zone along a shoreline mainly due to the action of breaking waves. The littoral transport is also called the longshore transport or the ''littoral drift''. <br />
===Description===<br />
Littoral transport is often described under the assumption that the shoreline is nearly straight with nearly parallel depth contours. This assumption is very often valid, especially if the sections of the shore are not too long and if a gradual transition between such sections is assumed. Under these circumstances, the littoral transport can briefly be described as follows.<br />
<br />
When waves approach the shoreline obliquely, refraction tends to turn the wave fronts so that they are almost parallel to the shoreline. At the same time, when approaching the [[breaker zone]], they undergo shoaling, which means that they become steeper and higher. Finally, the waves break. During the breaking process, the associated turbulence causes some of the seabed sediments to be brought into suspension. These suspended sediments, plus some of the sediments on the seabed, are then carried along the shoreline by the longshore current, which has its maximum near the breaker line. The two transport modes are referred to as suspended transport and bed load, respectively. The sum of these is the littoral drift.<br />
<br />
===Distribution of the Littoral Transport===<br />
[[Image:littoral distribution2.jpg|thumb|right|Fig. 2a ]]<br />
[[Image:littoral distribution5.jpg||thumb|right||Fig. 2b. Distribution of the littoral transport over a coastal profile for grain sizes <math>D_{50}</math> = 0.2 mm and 0.5 mm and for the wave heights HS = 1.0 m, 3.0 m and 5.0 m. Equilibrium profiles corresponding to the grain sizes have been used, refer to Fig. 6. Emperical width of littoral zone. ''Angle of incidence: \alpha; = 30^{0}. Calculated by LITPACK.'']]<br />
The magnitude of the littoral transport or drift, Q, depends on parameters, the most important of which are:<br />
<br />
*''Wave height.'' The littoral drift is proportional to the wave height to the power of approximately 3.<br />
*''Grain size.'' The littoral drift is inversely proportional to the grain size to the power of approximately 3.<br />
*''Wave incidence angle.'' The littoral drift is approximately proportional to <math>sin^{2.5}(2\alpha)</math>, where &alpha; is the wave incidence angle.<br />
<br />
It can be seen that the littoral drift varies strongly with several parameters. It is therefore crucial to have exact data when making littoral drift calculations. It is an important point that the littoral drift over the coastal profile depends not only on the hydrodynamics but also very much on the variation of the sediment characteristics over the profile. Hence, the sediment distribution along the coastal profile should be taken into account whenever possible.<br />
<br />
===Littoral Drift Budgets===<br />
A ''littoral drift budget'' for a coastal profile is the sum of littoral transport contributions caused by all the possible combinations of wave heights and directions, as well as tide and storm surge.<br />
<br />
Consider, for example, a coastline oriented north-south with the sea to the west. All wave components from south to west will yield northward littoral drift contributions, and all wave components from west to north will yield southward littoral drift contributions. The sum of the northward drift components is called the ''northward littoral drift'', and similarly is the sum of the southward drift components referred to as the ''southward littoral drift''. The difference between the northward and the southward littoral drifts is called the ''net littoral drift'', which is associated with a ''net littoral drift direction''. The sum of the northward and the southward drift rates is called the ''gross littoral drift'', which has no direction.<br />
<br />
====Littoral drift parameters====<br />
Littoral drift budgets can be made for any period relevant for the site under study as long as there are sufficient data. An overview of the magnitude of littoral drift is provided in the following table as a function of the following parameters:<br />
*The significant wave heights <math>H_{s}</math><br />
*The angle of incidence at '[[deep water]]' <math>\alpha_{0}</math> (20m has been used as '[[deep water]]')<br />
*A duration of 24 hours <br />
*Beach sand with <math>d_{50}= 0.25mm </math> <br />
*Calculations performed by LITPACK on the equilibrium profile corresponding to <math>d_{50}= 0.25mm </math> <br />
<br />
<br />
{|border="1" cellpadding="2" align="center"<br />
|+Table: Littoral transport rates Q as a function of <math>5_{s}= 0.25mm </math> and angle of incidence <math>\alpha_{0}</math> at deep water (20 m). Calculated by LITPACK. ''Note: <math>D_{50}</math>, H and MWD at 20m water depth''<br />
<br />
!rowspan="2" colspan="2"| Q[m<sup>3</sup>/24hrs]<br />
!colspan="6" align="center"|&alpha;<sub>0</sub><br />
|-<br />
! width="50"|5!! width="50"|15!! width="50"|30!! width="50"|45!! width="50"|60!! width="50"|75<br />
|-<br />
!rowspan="5"|H<sub>s</sub><br />
!1.0<br />
|50|| 100|| 300|| 350|| 300|| 150<br />
|-<br />
!2.0<br />
|400|| 1000|| 2,000|| 3,000|| 2,500|| 1,000<br />
|-<br />
!3.0<br />
|1,500||4,000|| 10,000||15,000||10000|| 5,000<br />
|-<br />
!4.0<br />
|4,000|| 10,000||30,000||40,000||35,000||15,000<br />
|-<br />
!5.0<br />
|8,000|| 25,000||65,000||100,000||85,000||35,000<br />
|}<br />
<br />
<br />
[[Image:drift budget_c.jpg|350px|thumb|right|Fig. 3.]]<br />
An important parameter in relation to the littoral drift conditions is the variation of the net transport with varying orientation of the coastline. If e.g. a groyne is constructed, this will initially block the transport resulting in net zero transport at this location. This means that the sand will [[accretion|accrete]] upstream of the groyne forming a coastline with the orientation, which gives zero transport. The efficiency of the groyne depends very much on the angle between the present orientation of the coastline and the orientation of net zero transport. If this angle is small, the groyne will be efficient, as it will be able to hold a long sand filet. If the angle is large, which is the case with a very oblique wave exposure, the groyne will only be able to hold a very short sand filet, which means that a groyne will not be an applicable type of coast protection in this case.<br />
<br />
====Net littoral drift====<br />
When discussing the littoral transport along a coastline in general, it is always the net littoral drift that is referred to unless otherwise specified. Gradients in the net littoral drift along a section of coast lead to '''coastline erosion or [[accretion]]'''. The gross littoral drift is important for backfilling of channels/trenches across the littoral drift zone, as all littoral drift situations lead to backfilling of the channel/trench.<br />
<br />
====What does littoral drift depend on?====<br />
The littoral drift also depends on the sea current, although to a much smaller extent than it depends on the longshore current. This means that the most important hydraulic parameter for the littoral transport is the wave conditions.<br />
<br />
The water-level mainly determines where in the coastal profile the transport will take place, but the water-level only influences the magnitude of the littoral drift to a lesser extent. However, the tide may have significant influence on the transport conditions for macro-tidal environments. Positive or negative correlation between the waves and the water-level variations may be of importance for sedimentation patterns near large structures. <br />
<br />
====Sediments and littoral drift====<br />
At many locations there is a considerable variation in the grain size depending on the distance from the coastline. Typically the sediments become finer with increasing distance from the coastline. This will, to some extent, blur the picture of the littoral drift given above.<br />
<br />
The fine cohesive sediments, which may be present in the outer part of the profile, will be in suspension over the entire water column and will also tend to spread over the entire coastal profile during strong wave exposure. The transport which this gives rise to is normally not considered a part of the littoral drift, as this only takes the non-cohesive sediments into consideration. The transport of the cohesive sediments thus only plays an indirect role in the stability of the coastal profile. The existence of this transport of fine suspended sediments will, however, be of importance in relation to sedimentation in ports and in trenches.<br />
<br />
[[Image:tombolo2.jpg|thumb|right|Fig. 4. Tombolo formation behind coastal breakwater]]<br />
The longshore transport is, as already mentioned, characterised by a combination of sediment moved along the seabed, the so-called ''bed load transport'', and of sediment in suspension, the so-called ‘’suspended load’’. Even when the sand is in suspension it is still relatively close to the seabed because of the relatively high ''fall velocity'' of sand grains. This means that any change in the hydrodynamics or [[bathymetry|bathymetric]] conditions will "immediately" result in a corresponding change in the transport capacity and therefore also in the morphology. This results for instance in the typical accumulation of sand behind even a relatively short, detached, coastal breakwater, as the accumulation of sand reflects the “immediate” response on the attenuated transport capacity behind the breakwater. It is not possible to guide the sand between the coastal breakwater and the shoreline if the breakwater has a length of more than around 0.5 times the distance from the shoreline. If the length of the breakwater is more than approximately 0.8 times the distance from the shoreline so much sand will be trapped that the breakwater will be connected to land by a [[tombolo]] formation. This immediate morphological response to even small changes in the littoral transport is also the reason why many attempts to construct island-ports with zero impact on the shoreline have failed. Most of them have been connected to land by [[tombolo]] formations.<br />
<br />
==Onshore and Offshore Transport and Equilibrium Coastal Profile==<br />
Varying wave conditions result in varying onshore and offshore transports over the coastal profile. These transports are, to some extent, reversible and therefore non critical in terms of long term coastal stability. However, extreme storm surge and wave exposure result in coastal erosion.<br />
<br />
===Erosion and rebuilding sequence===<br />
When the coastal profile is exposed to non extreme waves and storm surge, the sediments near the shoreline will be transported offshore and typically be deposited in a bar resulting in an overall flattening of the slope of the shoreface. However, the inner part of the shoreface as well as the foreshore will become steeper in this process, and the shoreline will recede. During the following periods of smaller waves, swell and normal water-level conditions, the bar will travel very slowly towards the coastline again, practically rebuilding the original coastal profile.<br />
<br />
During such a sequence of profile erosion and rebuilding, certain parts of the coastal profile may experience temporary erosion. This may not be recorded in profile surveys, because some rebuilding will already have taken place before it is possible to carry out surveys after the storm. It is important to take such temporary profile fluctuations into account when designing structures in the coastal zone. It is particularly important to have a sufficiently wide beach so that the temporary beach erosion will not cause erosion of the coast.<br />
<br />
===Coastal profile===<br />
This onshore and offshore transport is closely related to the form of the coastal profile. Several investigations have revealed that a coastal profile possesses an average, characteristic form, which is referred to as the theoretical equilibrium profile. The equilibrium profile has been defined as "a statistical average profile, which maintains its form apart from small fluctuations, including seasonal fluctuations". The depth d [meters] in the equilibrium profile increases exponentially with the distance x from the shoreline according to the equation<ref name=Dean/><br />
<br />
:<math>d=Ax^{m}</math> [x and d in meters]<br />
<br />
where A is the dimensionless steepness parameter and m is a dimensionless exponent. Based on fitting to natural upper shoreface profiles, Dean, 1987<ref name="Dean">Dean, R.G., 1987. "Coastal Sediment Processes: Toward engineering solutions." Proceedings Coastal Sediments '87, Am. So. Civ. Eng., 1-24.</ref> has suggested an average value of m = 0.67. However the value of m is subject to large variability dependent of the beach type expressed by the dimensionless fall velocity <math>\Omega=H_{0}/\omega_{s}T</math> where <math>H_{0}</math> is the deep water wave height, T is the wave period and <math>\omega s</math> is the sediment fall velocity. The value of m varies typically between m ~ 0.4 for reflective beaches (<math>\Omega<1.5</math>) and m ~ 0.8 for dissipative beaches (<math>\Omega>5.5</math>).<ref>Cowell, P.J., Hanslow, D.J. and Meleo, J.F., 1999. The Shoreface: In: A.D. Short (editor), Handbook of Beach and Shoreface Morphodynamics, Wiley and Sons, Chichester, 29-71.</ref><ref>Masselink, G. and Huges, M. G., 2003. Introduction to Coastal Processes adn Geomorphology. Published by Hodder Arnold. ISBN 0340764104.</ref>.<br />
<br />
<br />
The steepness parameter A has empirically been related<ref name="Dean"/> to the sediment fall velocity <br />
<math>\omega_{s}</math> as follows:<br />
<br />
:<math>A=0.067\omega_{s}^{0.44}</math> [<math>\omega_{s}</math> in cm <math>s^{-1}</math>]<br />
<br />
Values for A as a function of the mean grain size <math>d_{50}</math> is shown in the table below.<br />
<br />
{|border="1" align="center"<br />
|+Table: Correlation between mean grain size d<sub>50</sub> in mm and the constant A in Dean’s equilibrium profile equation<br />
!width="100"|d50<br />
!width="75"|0.10<br />
!width="75"|0.15<br />
!width="75"|0.20<br />
!width="75"|0.25<br />
!width="75"|0.30<br />
!width="75"|0.50<br />
!width="75"|1.00<br />
!width="75"|2.00<br />
!width="75"|5.00<br />
!width="75"|10.00<br />
|-align="center"<br />
!width="100"|A<br />
|0.043||0.062||0.080||0.092||0.103||0.132||0.178||0.234||0.318||0.390<br />
|}<br />
<br />
<br />
It is seen that the equilibrium profile does not depend on the wave height. The reason for this is that the water depth limits the wave height inside the [[surf zone]]. However, the wave height decides the width of the littoral zone, within which the equilibrium shoreface concept is valid. Thus, the equilibrium profile is only valid for the littoral zone, i.e. out to the [[Closure depth]] d<sub>l</sub>:<br />
<br />
:<math>d_{1} = 2.28H_{S,12h/y} - 68.5^{H^{2}_{S,12h/y}}gT^{2}_{s}</math><br />
<br />
<br />
[[Image:equilibrium profiles.jpg|thumb|Fig. 5. Equilibrium profiles for grain sizes 0.15, 0.2, 0.3, 0.5, 1.0, 10 and 30 mm.]]<br />
[[Image:emperical width.jpg|thumb|Fig. 6. Empirical width of littoral zone as a function of the mean grain size for various wave climates represented by <math>H_{S,12h/y}</math>]]<br />
<br />
The width of the littoral zone and the slope of the shoreface thus depend on the mean grain size as well as on the wave conditions.<br />
<br />
The equilibrium profile becomes increasingly steeper with increasing grain size. Typical equilibrium profiles for different grain size characteristics are presented in Fig. 5. <br />
<br />
The width of the littoral zone as a function of the mean grain size and for different wave climates, represented by <math>H_{S,12h/y}</math>, is presented in Fig. 6.<br />
<br />
These figures can be used in preliminary design considerations for artificial beaches and reclamation areas fronted by natural slopes.<br />
<br />
It is evident from these correlations between grain size, equilibrium profile and wave conditions that it is very important in beach nourishment to use materials as coarse as or coarser than the native material. Otherwise the nourished sand will immediately be transported offshore in nature’s attempt to form the new and flatter equilibrium profile, which fits the finer sand.<br />
<br />
In the real world there is often a sorting of the sediments in the active coastal profile; the mean grain size decreases with increasing distance from the shoreline. If this variation is introduced into the considerations concerning the equilibrium profile, a more accurate representation of the equilibrium profile at a specific site is obtained.<br />
<br />
The concept of equilibrium profiles is a rather crude representation of the coastal profile conditions since it neither includes nor explains the occurrence of bar formations, etc. However, the concept of the equilibrium profile is a rather practical “tool” for the analysis of coastal conditions and, as already mentioned, for preliminary design considerations. <br />
<br />
If the geological coastal profile at a location is flatter than the calculated equilibrium profile, the wave action in the profile will tend to form the equilibrium profile, which means that material will be moved towards the shore. However, at a certain location towards the shore, there is not sufficient wave energy to move the sand any further and a barrier with a corresponding lagoon is formed.<br />
<br />
The equilibrium concept can also explain why shore and coast erosion take place at locations where the equilibrium profile is already established, when such profiles are exposed to the combined action of storm waves and storm surge (tidal wave). The increased water level will correspond to a profile, which is too steep compared to the equilibrium profile. At a certain distance from the shoreline the water will consequently be too deep relative to the equilibrium depth. Nature will compensate by transporting sand from the beach towards the sea in an attempt to re-establish the equilibrium profile, which fits the temporary high water level. This will result in setback of the shoreline; however, if the beach is not sufficiently wide for this adjustment, the sediment will be taken from the cliff or dunes. The amount of erosion during a storm thus depends primarily upon the magnitude of the storm surge and its duration. It is evident from this description that a wide beach is a precondition for a stable coastline. Coast protection can thus be established by providing a wide beach through beach or foreshore nourishment. After the storm, the material, which was brought offshore during the storm surge conditions, will to a great extent be transported slowly back to the beach, however extreme storm surge/wave events will result in a permanent offshore loss of material.<br />
<br />
===Cross-shore sediment transport===<br />
<ref name="Aagard"/>Once the sediment is brought up into the water column it becomes available for transport by the various hydrodynamic processes. In the longshore dimension, the transport is accomplished almost exclusively by mean currents because the longshore component of wave orbital motions is small. Longshore sediment transport gradients are small on long straight coasts and hence the morphological impact is small except in the vicinity of shoreline discontinuities. <br />
<br />
<ref name="Aagard"/>In the cross-shore dimension, however, the transport is considerably more complex. The net sediment transport at a given point in the profile is often a balance between an onshore transport caused by skewed incident short wave motions, an offshore transport caused by mean currents and a transport caused by long waves which can be either onshore or offshore directed<ref name="Aagard, Masselink">Aagaard, T. and Masselink, G., 1999. The Surf Zone. In: A.D.Short (ed) Handbook of Beach and Shoreface Morphodynamics, Wiley Interscience, pp.72-118. </ref>. Consequently shore-normal sediment transport gradients can become large and morphological changes created by such transport gradients are often considerable, spatially as well as temporally. <br />
<br />
<ref name="Aagard"/>[[Accretion]] occurs in zones of sediment transport convergence whereas erosion occurs in zones of divergence. As an example, longshore bars are often formed near, or in the zone of wave breaking because the sediment transport outside the breakpoint is often dominated by the short waves and onshore directed because of the wave skewness while inside the breakpoint, sediment transport is dominated by the offshore directed undertow. The position of the bars in the profile can then fluctuate in phase with the wave energy conditions: When waves are small, the breakpoint is located close to the shoreline and the bars tend to move onshore while large waves break far from the shoreline and the bars move offshore.<br />
<br />
==Transport of non-cohensive sediments==<br />
Most of the transport of non-cohesive sediments (sand) takes place in wave-dominated environments. There are, however, locations where the transport of sand is mainly dominated by the current. In relation to coastal morphology the ''tidal inlet'' is the most important. <br />
<br />
===Description of tidal inlets===<br />
A tidal inlet is the connection between the sea and a lagoon, which is exposed to shifting tidal currents.<br />
<br />
Flood tide causes the tidal current to run from the sea into the lagoon and ebb tide goes in the opposite direction. The exchanged water mass during a tidal cycle is called the ''tidal volume.'' This can roughly be calculated as the surface area of the lagoon times the tidal range.<br />
<br />
The tidal current in a tidal inlet on a coastline is responsible for the exchange of sand between the littoral zone and the lagoon. This sand transport typically results in varying depths and shifting locations of the inlets and in the formation of lagoon shoals ''(flood shoals)'' and offshore shoals ''(ebb shoals)''. At the same time the longshore transport interferes in these processes resulting in curved bar formations crossing the inlet as well as the formation of sand spits and possible shifting of the tidal inlet along the shore. All in all, it is a very mobile environment, which is not recommended for development of any kind.<br />
<br />
Tidal inlets are very often regulated and fixed by inlet jetties and they are frequently dredged to allow navigation. An important aspect in relation to regulated tidal inlets on littoral transport coastlines is that the jetties constitute a blockage of the littoral transport. This results in sand accumulation on the updrift side and lee side erosion along the [[downdrift]] coastline, unless special precautions are taken. When the sand accumulation on the updrift side reaches the tip of the jetty, the sand will start to bypass and this will cause sedimentation in the inlet. Normally the sand does not pass the dredged channel and therefore it does not nourish the lee side beach.<br />
<br />
===Added complexities===<br />
The above description of tidal inlets is greatly simplified and presents only the mechanisms in a very broad outline. The hydrodynamic and sediment transport conditions in tidal inlets are very complicated, as a tidal inlet always constitutes a delicate balance between the “forces” which keep it open, namely the tidal exchange, and the “forces” which tend to close it, namely the littoral transport processes. It adds to the complexity of tidal inlets that many different time scales are involved, the most important of which are outlined below:<br />
<br />
*[[Semi-diurnal]] and [[diurnal]] tidal components<br />
*Neap and spring with fortnightly periods<br />
*Seasonal variations in water-level, storm surge and wave conditions<br />
*Very wide time scales for the wave conditions: from seconds for single waves to days for storm duration to seasons for variations in general wave climate to years for the recurrence of extreme wave events<br />
<br />
===Studies on tidal inlets===<br />
Tidal inlet studies can be performed at many levels, from<br />
*a parametric empirical stability analysis involving only the main parameters such as the tidal parameters, the cross section area of the inlet and the wave energy; to <br />
*a complete study involving numerical modelling of hydrodynamics, waves, sediment transport and morphological evolution<br />
<br />
==References==<br />
<references/><br />
<br />
==Further reading==<br />
:Mangor, Karsten. 2004. “Shoreline Management Guidelines”. DHI Water and Environment, 294pg.<br />
<br />
{{author<br />
|AuthorID=13331<br />
|AuthorFullName=Mangor, Karsten<br />
|AuthorName=Karsten}}<br />
[[category:Theme 5]]<br />
[[Category:Coastal processes, interactions and resources]]<br />
[[Category:Hydrodynamics]]<br />
[[category:Coastal erosion]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=The_Blue_Book&diff=30648
The Blue Book
2009-07-09T13:17:00Z
<p>Wouter Kreiken: {{featured}}</p>
<hr />
<div>{{featured}}<br />
<br />
== An Integrated Maritime Policy for the European Union -The '''Blue Book'''<ref>COM(2007)575 final, Brussels, 10.10.2007 -An Integrated Maritime Policy for the European Union -Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions<br />
</ref> ==<br />
<br />
The European Commission launched a comprehensive consultation and analysis of how Europe relates to the sea. <br />
''(See also the [[Green Paper for a EU Maritime Policy|Green Paper for an EU Maritime Policy]])''<br />
<br />
Building in this valuable input the Commission presented, on 10 October 2007, its vision for '''an Integrated Maritime Policy for the European Union''', also called the '''Blue Book'''. This vision is based on the clear recognition that all matters relating to Europe's oceans and seas are interlinked, and that sea-related policies must develop in a joined-up way if are to reap the desired results<br />
<br />
[[Image:Diver_right.jpg|100px|right|thumb|Logo of the Blue Book]]<br />
<br />
The Blue Book is accompanied by the other 3 documents:<br />
<br />
*a [http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=COM:2007:0574:FIN:EN:PDF Report on the stakeholder consultation results]<br />
*a detailed [http://ec.europa.eu/maritimeaffairs/pdf/ActionPaper/action_plan_en.pdf Action Plan]-aiming at exploring the full potential of sea-based economic activity in an environmental sustainable manner<br />
*an [http://ec.europa.eu/maritimeaffairs/pdf/summary/sec_2007_1280_en.pdf Impact Assessment]<br />
<br />
The '''Blue Book''' lays the foundation for the '''governance framework''' and '''cross-sectoral tools''' necessary for an EU Integrated Maritime Policy.<br />
<br />
It also sets out the '''main actions''' that the Commission will pursue, during the course of this mandate, in the following five '''action areas''':<br />
<br />
*Maximising the Sustainable Use of the Oceans and Seas<br />
*Building a knowledge and innovation base for the maritime policy<br />
*Delivering the Highest Quality of Life in Coastal Regions<br />
*Promoting Europe's Leadership in International Maritime Affairs<br />
*Raising the Visibility of Maritime Europe<br />
<br />
== A Governance Framework ==<br />
An Integrated Maritime Policy requires a '''governance framework''' that applies the integrated approach at every level<br />
<br />
Related actions by the Commission:<br />
*invite Member States to draw up national integrated maritime policies, working closely with stakeholders, in particular the coastal regions;<br />
*propose in 2008 a set of guidelines for these national integrated maritime policies and report annually on EU and Member States' actions in this regard from 2009;<br />
*organise a stakeholder consultation structure, feeding into further development of the maritime policy and allowing exchange of best practices<br />
<br />
== Cross-sectoral tools ==<br />
An integrated governance framework for maritime affairs requires horizontal planning tools that cut across sea-related sectoral policies and support joined up policy making. The most relevant tools are the following:<br />
<br />
'''A European network for maritime surveillance''' -for the safe and secure use of marine space<br />
<br />
Related actions by the Commission:<br />
*promote improved cooperation between Member States' Coastguards and appropriate agencies<br />
*take steps towards a more interoperable surveillance system to bring together existing monitoring and tracking systems used for maritime safety and security, protection of the marine environment, fisheries control, control of external borders and other law enforcement activities<br />
<br />
'''Maritime Spatial Planning and ICZM''' -for sustainable decision-making<br />
<br />
Related actions by the Commission:<br />
*develop a roadmap in 2008 to facilitate the development of maritime spatial planning by Member States<br />
<br />
'''A comprehensive and accessble source of Data and Information''' -for informed decision-making<br />
<br />
Related actions by the Commission:<br />
*take steps in 2008 towards a European Marine Observation and Data Network (building inter alia on the GMES initiative)<br />
*promote the multi-dimensional mapping of Member States' waters, in order to improve access to high quality data<br />
<br />
== The Blue Book and Integrated Coastal Zone Management (ICZM) ==<br />
The Blue Book recognizes that existing planning frameworks have a largely terrestrial focus and often do not address how coastal development may affect the sea and vice-versa.<br />
<br />
In this regard, the Blue Book acknowledges that, following the EU Recommendation 2002/413/EC, Member States have begun to use ICZM to regulate the spatial deployment of economic activities and to set up spatial planning systems for Europe's coastal waters. Thus, the Blue Book proposes [[ICZM]] as a cross-sectoral tool -along with [[Theme 3|Maritime Spatial Planning]]-, supporting joined up policy making in the integrated governance framework for maritime affairs. <br />
<br />
As decision-making competence in this area lies with the Member States, the Blue Book states that what is needed, at the European level is ''a commitment to common principles and guidelines to facilitate the process in a flexible manner and to ensure that regional marine ecosystems that transcend national maritime boundaries are respected''.<br />
<br />
The Blue Book states that ''a system for exchange of best practice among authorities engaged in marine spatial planning and ICZM will be set up''. However, it is important to note that it is not clearly acknowledged if this is one of the actions that the Commission will undertake.<br />
<br />
== Further reading ==<br />
<br />
* See also ''[[The European Context|EU coastal related policies]]''<br />
<br />
* See also ''[[Capacity Building in the frame of EU ICZM related policies]]''<br />
<br />
== External links ==<br />
<br />
[http://ec.europa.eu/maritimeaffairs/dev_imp_en.html Development of an Integrated Maritime Policy for the EU]<br />
<br />
[http://ec.europa.eu/maritimeaffairs/contrib_rc_en.html EU Maritime Affairs Documentation Centre]<br />
<br />
== References ==<br />
<references/><br />
<br />
<br />
{{author<br />
| AuthorID=12516<br />
| AuthorFullName=Garriga, Maica<br />
|AuthorName=Maicagarriga}}<br />
<br />
<br />
[[category: Integrated coastal zone management]]<br />
[[category:International coastal organisation]]<br />
[[category:Policy and decision making in coastal management]]<br />
[[category:theme 10]]<br />
[[category:Education, awareness and capacity building in integrated coastal zone management]]<br />
[[category:Techniques and methods in coastal management]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Marine_Plankton&diff=30647
Marine Plankton
2009-07-09T13:15:50Z
<p>Wouter Kreiken: {{featured}}</p>
<hr />
<div>{{featured}}<br />
<br />
== '''Plankton in the open ocean''' ==<br />
<br />
=== Introduction ===<br />
Take a second to consider the scale of our oceans. Approximately two thirds of our planet is covered in seawater. The oceans teem with life, yet humans are ill-equipped to explore this environment without specialist equipment. The fascinating world of [[plankton]] lies hidden beneath the surface of our seas. <br />
<br />
[[Image:Sieburth-et-al-1978-L&O-fig.jpg|thumb|left|450px|''The ‘Sieburth-scale’. Copyright 2009 by the American Society of Limnology and Oceanography.'' <ref name = "Sieburth"> Sieburth, J. Mn., Smetacek, V. & Lenz, J. 1978. Pelagic ecosystem structure: Heterotrophic compartments of the plankton and their relationship to plankton size fractions. ''Limnology and Oceanography'' 23(6): 1256-1263.</ref>]]<br />
<br />
[[Plankton]] consists of a diverse range of living organisms that spend at least a part of their life cycle suspended in water. The term [[plankton]] is actually a Greek word, meaning ''that which is made to wander or drift''. This term is further divided into the [[phytoplankton]] and [[zooplankton]], meaning plant- (Gk. ''phyto'') and animal- (Gk. ''zoön'') drifters respectively. <br />
<br />
Planktonic organisms may have a limited ability to control their fine-scale distribution in the water column, but are otherwise at the mercy of oceanic currents and water movements. Holoplantkon refers to those organisms that spend their entire life in the plankton, as opposed to the meroplantkon, which are only planktonic for a part of their lives. Organisms that are capable of resisting the powers of currents, such as fish and squid, are referred to as neckton. <br />
<br />
Planktonic organisms are typically classified into broad size categories according to the ''' ‘Sieburth-scale’ ''', originally proposed in 1978. Viruses and jelly fish sit at opposite ends of this scale, which runs from fractions of a millimetre to metres. <br />
<br />
<br />
[[Image:AYool_SEAWIFS_annual.jpg|thumb|right|450px|''Average sea surface chlorophyll for the period January 1998 to December 2006 from the SeaWIFS satellite. The average is composed from 8 day composites with a spatial resolution of 0.5° in latitude and longitude. Chlorophyll is in mg chl m-3 (note that the colour scale is logarithmic). It is plotted here using a Mollweide projection (using MATLAB and the M_Map package). Image provided courtesy of Dr A. Yool.'']]<br />
<br />
==='''Plants of the ocean'''===<br />
<br />
[[Photosynthesis]] is the process by which inorganic building blocks such as carbon dioxide (CO2) and water (H2O) are combined using energy from the Sun to produce organic compounds. Organisms that are capable of this process can be referred to as photoautotrophs (Gk. ''Photon'', ''auto'', ''trophe''; light-self-nutrition) and primary producers. Chlorophyll and other similar pigments are found in light-harvesting organelles called chloroplasts. These are present in all species of [[phytoplankton]]. Organic matter formed by these organisms forms the basis of almost all food chains. Approximately 50% of global primary production occurs in the oceans.<br />
<br />
On land, plants are typically large, conspicuous organisms; trees, herbs, bushes and grasses etc. They have root structures to take up water and nutrients from the soils beneath them, and also to provide anchorage. Marine plants, the [[phytoplankton]], are fundamentally different. They are microscopic, single-celled organisms. Smaller objects have a greater surface area relative to their volume, and hence mass. Being small in the oceans confers several advantages: [[Phytoplankton]] cells are so small that their weight is, to a large extent, offset by the frictional drag exerted on them by the water. Thus, they sink very slowly, enabling them to stay within the surface, sunlit waters. Many species of [[phytoplankton]] have ornate spines and appendages which appear to both increase drag, and serve as defence mechanisms. [[Phytoplankton]] cells do not have roots, and must take up nutrients from their surrounding environment. Having a large surface area relative to their volume ensures that they maximise their chances of attaining enough resources for growth. <br />
<br />
<br />
[[Image:coscinodiscuswailesii_pnw.jpg|thumb|left|450px|''The diatom'' Coscinodiscus wailesii. ''The two ‘valves’ of the cell can be seen in the top left image. Image taken by M. Hoppenrath, provided courtesy of Plankton*Net (image # 12641) <ref name = "Plankton Net"> Plankton Net; Data Provider at the Alfred Wegener Insitute for Polar and Marine Research: http://planktonnet.awi.de/</ref>.'']]<br />
<br />
==== Diatoms ====<br />
Perhaps the most conspicuous group of phytoplankton are the diatoms. Their name is derived from the Greek words ''dia'' and ''temnein'', literally ''cut in half''. This seemingly bizarre name arose because of the nature of their cell wall, or frustule, which is made up of two halves or valves like that of a laboratory petri dish. The silicon-rich frustule is perforated by numerous pore-like structures which can give the cell a beautiful appearance when viewed under high magnification. These connect the cell to the outside seawater. They also help strengthen the cell wall whilst reducing its mass.<br />
<br />
In temperate latitudes, diatoms are well known for their capacity to form immense blooms in spring as the sun’s energy infiltrates nutrient rich surface waters. Their rapid growth rates are thought to confer them a competitive advantage during these times, only to be thwarted as silicate concentrations become depleted. Diatoms produce large quantities of mucus when nutrient stressed, causing them to coagulate and sink into the deep ocean. The ecological significance of this is still not fully understood as it appears to represent a genetic dead-end i.e. once in the deep sea, they do not possess a mechanism to enable them to return to the surface. Diatoms are one of the major producers of omega-3 fatty acids, which are now widely reputed as being beneficial for human health. <br />
<br />
[[Image:wiktor_cr2_20090206105727_small.jpg|thumb|left|375px|''The flagellate'' Leucocryptos marina. ''Image taken by Wiktor, provided courtesy of Plankton*Net (image # 58765) <ref name = "Plankton Net"> Plankton Net; Data Provider at the Alfred Wegener Insitute for Polar and Marine Research: http://planktonnet.awi.de/</ref>.'']]<br />
<br />
==== Flagellates ====<br />
Much of the remainder of marine plants belong to a diverse assemblage of unicellular organisms called flagellates. These cells possess a whip-like flagellum. It is at this end of the plankton size spectrum that the distinction between plant and animal becomes blurred. The flagella are used to propel the cell, enabling them to ‘swim’ upwards towards the sunlit waters. Some flagellates, although mobile, contain photosynthetic pigments and are thus autotrophic. Others are devoid of pigments and hence are heterotrophic: they either absorb organic matter directly from their surroundings, or actively capture and ingest bacterial prey. Others still are capable of both autotrophic and heterotrophic nutrition: they are mixotrophic.<br />
<br />
===== Dinoflagellates =====<br />
Dinoflagellates are comparatively large flagellates. They are so-called because of the way that they ‘whirl’ or corkscrew through the water (Gk. ''Dinos''; whirling). Approximately half of all the dinoflagellates are autotrophic and those belonging to the other half are either heterotrophs or mixotrophs (see below). Many armour their cell wall with cellulose plates, forming the theca. In some species of thecate dinoflagellates the plates form long spines which serve to increase the cell’s frictional drag and also act as a grazing deterrent. The ‘naked’ dinoflagellates lack any such extracellular armour. <br />
<br />
[[Image:fatima_santos_ceratium_pentagonum_madeira_170706_1_20081229181256_small.jpg|thumb|left|200px|''The thecate dinoflagellate'' Ceratium pentagonum. ''Image taken by Fatima Santos, provided courtesy of Plankton*Net (image # 58716) <ref name = "Plankton Net"> Plankton Net; Data Provider at the Alfred Wegener Insitute for Polar and Marine Research: http://planktonnet.awi.de/</ref>.'']]<br />
<br />
Several species of dinoflagellates bioluminesce: They produce a flicker of light when disturbed. This is frequently observed by SCUBA- (Self Contained Breathing Apparatus) divers at night when they turn off their torches and disturb the water with their hands. Some species of dinoflagellates can produce virulent neurotoxins such as saxitoxin and brevetoxin. These can cause serious harm if they enter the human food chain. For this reason, monitoring programmes exist to ensure that the fish and shellfish that we consume are safe.<br />
<br />
[[Image:fjouenne_sbrsom0602w_20080516171714_small.jpg|thumb|right|350px|''The flagellate'' Phaeocystis globosa. ''Image taken by Fjouenne, provided courtesy of Plankton*Net (image # 57870). <ref name = "Plankton Net"> Plankton Net; Data Provider at the Alfred Wegener Insitute for Polar and Marine Research: http://planktonnet.awi.de/</ref>'']]<br />
<br />
===== Phaeocystis =====<br />
Phaeocystis is a particularly interesting genus of flagellate. It can exist as small, individual cells or large gelatinous colonies. The latter are long since known for fouling fishermen’s nets. Large blooms of these organisms can occur throughout the world, particularly in the temperate and polar seas. These are problematic for fish as the gelatinous colonies can clog their gills. Indeed, blooms of Phaeocystis can trigger dramatic changes in the structure of marine ecosystems owing to its seemingly unpleasant nature. It produces a strong smelling compound called dimethylsulfupropionate (DMSP) which is thought to serve as a grazing deterrent. It is also suggested to play a role in climate regulation by stimulating the formation of clouds. There is growing concern that the frequency and magnitude of Phaeocystis blooms in coastal waters are increasing as a result of eutrophication.<br />
<br />
[[Image:vaulot_118-14_20070425152053_w.jpg|thumb|left|300px|''The coccolithophorid'' Emiliania huxleyi var. corona. ''Image taken by Claudia Sprengel & Jeremy Young, provided courtesy of Plankton*Net (image # 56470). <ref name = "Plankton Net"> Plankton Net; Data Provider at the Alfred Wegener Insitute for Polar and Marine Research: http://planktonnet.awi.de/</ref>'']]<br />
<br />
===== Coccolithophorids =====<br />
Coccolithophorids are another important group of flagellates. Each cell is covered by an array of intricate plates or coccoliths. These are made from calcium carbonate, the material that teachers use to write on black boards. The exact function of the coccoliths is unknown. The coccoliths have been suggested to serve as a grazing deterrent, to help maintain buoyancy and to act as an ultra-violet radiation filter. Certain species produce enormous blooms that are clearly visible from space, causing the water to have a milky-white appearance that fishermen refer to as ‘white water’. <br />
<br />
[[Image:fjouenne_sbrbill0204w_20080306182435_small.jpg|thumb|right|150px|''The cyanobacterium'' Synechococcus sp. ''Image taken by Chantal Billard, provided courtesy of Plankton*Net (image # 57783). <ref name = "Plankton Net"> Plankton Net; Data Provider at the Alfred Wegener Insitute for Polar and Marine Research: http://planktonnet.awi.de/</ref>'']]<br />
<br />
==== Cyanobacteria ====<br />
<br />
Cyanobacteria, or the '''blue-green algae''', play a unique role in the nutrient-depleted waters of the open oceans. They are capable of converting inert atmospheric nitrogen (N2) into organic forms such as nitrate (NO3-) and ammonia (NH3). This process is known as nitrogen fixation. It provides a valuable source of nitrogen in areas of the oceans where it is otherwise absent.<br />
<br />
==='''Animals of the ocean'''===<br />
The extremely diverse collection of organisms referred to as [[zooplankton]] is all but hidden from the public eye. It is presumably for this reason that some of the most numerous animals on our planet remain without common names. Every major phylum of the animal kingdom is represented in the zooplankton, at least by a larval stage. Insects are a conspicuous absentee, and various hypotheses have been proposed to explain this <ref name = "Marine insect homepage"> Marine insect home page: http://cgi.unk.edu/hoback/marineinsects/home.html</ref>. <br />
<br />
==== Protozoa ====<br />
Protozoa (Gk. ''Proton'', ''zoön''; first-animal) is a loosely-defined collection of uni-cellular, heterotrophic organisms. Together with small multi-cellular organisms they form the '''microzooplankton'''. As noted above, the distinction between plant and animal becomes blurred as we travel down towards the smaller end of the plankton size spectrum. <br />
<br />
[[Image:alexandra_kraberg_strobilidium_g47_40_20070811000007_small.jpg|thumb|left|250px|''The naked ciliate'' Strobilidium sp. ''Image taken by Alexandra Kraberg, provided courtesy of Plankton*Net (image # 16733). <ref name = "Plankton Net"> Plankton Net; Data Provider at the Alfred Wegener Insitute for Polar and Marine Research: http://planktonnet.awi.de/</ref>'']]<br />
<br />
Ciliates are a particularly important group of protozoa. As their name suggests, they possess numerous hair-like features that fulfil several functional roles including movement, feeding and sensing the external environment. Heterotrophic ciliates focus on prey much smaller than themselves, ingesting bacteria and/or nanoflagellates. They play key roles in the '''microbial loop'''. <br />
<br />
[[Image:Dinophysis feeding.jpg|thumb|right|250px|''Dinoflagellate feeding on a ciliate via the peduncle. Reproduced with permission from Wiley-Blackwell <ref name = "Hansen & Calado, 1999 "> Hansen, P.J. & Calado A. J. 1999 Phagotrophic mechanisms and prey selection in free-living dinoflagellates. J. Eukaryot. Microbiol. 46(4) 382-389.</ref>'']]<br />
<br />
Heterotrophic dinoflagellates frequently attack prey of equal or larger size than themselves. Some feed by engulfing their prey whole, while others suck out the contents of their prey via a feeding appendage called the peduncle.<br />
<br />
==== [[Crustacea]] ====<br />
Planktonic crustaceans are in many ways analogous to the insects on land. They typically dominate [[zooplankton]] communities, representing a crucial link in oceanic food chains. The term crustacean is derived from the Latin word “crustaceus”, meaning ‘having a shell or crust’. This refers to the jointed armour that envelops their bodies, made from a tough material called chitin (Gk. ''chiton'', a tunic). This rigid external skeleton restricts the growth process, and must first be shed before an individual can increase in size. Growth and development of all crustaceans is therefore achieved through a series of moults. It is common for the body form of an adult to be considerably different to that of the young.<br />
<br />
[[Image:Calanus finmarchicus.jpg|thumb|left|250px|''The copepod'' Calanus finmarchicus. ''Image taken by Daniel Mayor.'']]<br />
<br />
In the words of Sir Alister Hardy, the world-renowned zooplankton biologist, ''“the crustaceans of the marine plankton par excellence are the Copepoda” ''<ref name = "Hardy"> Sir Alistair Hardy, 1959. The open sea – its natural history: Part I The world of plankton, 2nd Edition. Readers Union, Collins, London</ref>. The abundance and biomass of copepods in our oceans defies belief. Some people maintain that copepods are the most numerous animal on our planet. They are found in all the seas on Earth, and have developed numerous strategies to survive in even the harshest conditions. Copepods may be herbivorous, omnivorous, carnivorous or even detritivorous. They typically have an array of specialised feeding appendages that enable them to effectively sieve-out or grasp their food from the surrounding water. It is these oar-like feet that give copepods their name (Gk. ''Kope'', ''Podo''; oar-foot). The sheer numbers of these organisms necessitates that they play major roles in the ecology of our seas. Copepods represent a crucial interface between phytoplankton and fish. They are often the first prey of fish larvae, so a healthy population of these tiny creatures is essential for healthy fish stocks.<br />
<br />
[[Image:Meganyctiphanes_norvegica2.jpg|thumb|right|450px|''The northern krill'' Meganyctiphanes norvegica. ''Image taken by Øystein Paulsen, provided courtesy of MAR-ECO <ref name = "MAR-ECO"> MAR-ECO: http://www.mar-eco.no/</ref>.'']]<br />
<br />
'''Euphausids''' are relatively large (10-50 mm) shrimp-like animals that are more commonly known as krill. They are thought be omnivores, filtering out phytoplankton and similar-sized microzooplankton from seawater. Krill are often found in large swarms. This is thought to confuse predators that are searching for an individual. Euphausids (Gk. ''Phausis''; Shining light) are so-called because they have light-producing organs. Exactly why they produce light remains unknown. It may be involved in mate-location, social interaction or camouflage. Krill are super-abundant, particularly in the polar seas. They represent a staple food source for a diverse array of animals, ranging from fish and penguins to seals and whales.<br />
<br />
[[Image:Hyperia.jpg|thumb|right|400px|''The planktonic amphipod'' Hyperia macrocephala. ''Image taken by Uwe Kils.'']]<br />
<br />
[[Image:Ctenophore1.jpg|thumb|right|400px|''A pelagic ctenophore. Image taken by Marsh Youngbluth, provided courtesy of MAR-ECO <ref name = "MAR-ECO"> MAR-ECO: http://www.mar-eco.no/</ref>.'']]<br />
<br />
'''Amphipods''' are another important type of planktonic crustacean. They have large (sometimes enormous), well-developed eyes at the front of their head. These, together with pincer-type feeding appendages, are used to actively seek-out and capture their prey. The striking appearance of planktonic amphipods is reputed to have inspired the form of the creature in Ridley Scott’s 1979 film ‘Alien’. Some amphipods have a tendency to swarm like krill, whereas others live in association with gelatinous organisms such as jellyfish and salps. Upper ocean amphipods are eaten by an array of larger animals, including fish, birds and marine mammals. Deep water amphipods are important scavengers, and are always amongst the first animals to arrive when a new food source becomes available.<br />
<br />
Many crustacean zooplankton undertake a daily migration, moving into the upper, food-rich waters at night, and descending into the inky depths during the day. This behaviour continues throughout the winter, despite the surface layers being devoid of food. It is thought that '''‘diel vertical migration’''' is a tactic to avoid predators that feed visually.<br />
<br />
==== '' 'Jellies' '' ====<br />
The oceans harbour an enormous array of gelatinous organisms, or '' ‘jellies’ '', that range in size from millimetres to meters. They have soft, translucent and often fragile bodies. The latter makes them notoriously difficult to sample in a quantitative manner. This has led to the significance of gelatinous organisms in marine ecosystems being underestimated historically. A common feature of all jellies is that they are carnivorous, although some contain endosymbiotic algae that provide sugars and other carbohydrates via photosynthesis.<br />
<br />
Jellyfish are in fact not fish at all. They belong to a collection of organisms known as cnidarians. They are distinguished by the presence of nematocysts or cnidocytes which are stinging cells. These serve as efficient weapons, firing tiny dart-like structures that deliver neurotoxins into their prey. Jellyfish are known to form large blooms. This largely reflects their seasonal reproductive efforts. It has been suggested that the frequency and magnitude of jellyfish blooms has increased as a result of overfishing. However, there are currently too few data to substantiate or refute this claim. Jellyfish are consumed by other jellyfish, as well as fish and turtles.<br />
<br />
Ctenophores are distinct from jellyfish because they do not possess nematocysts. They are more typically known as the comb jellies (Gk. ''kteis'', ''ktenos''; comb), owing to the 8 rows cilia which have a comb-like appearance. The rhythmic beating of these tiny hairs provides propulsion for these animals. The cilia refract light like a prism, giving rise to wave upon wave of rainbow colours that sweep over their body. In the 1980’s an invasive American species of ctenophore was accidentally introduced into the Black Sea via a ship’s ballast water. The introduced ctenophore became the dominant consumer of zooplankton, removing the prey items for fish larvae. Commercial fisheries went into decline as a result of this invasive species, causing massive socio-economic disruption in the region.<br />
<br />
'''Salps''', '''doliolids''', '''pyrosomes''' and '''larvaceans''' are pelagic '''tunicates'''. They range in size from a few millimetres to metre-long colonies. Typically they have a barrel-shaped body that has two openings – one for taking water in, and the other for allowing water to be pumped out. Muscular contractions and rhythmic beating cilia draw water over a sticky mucus basket that sieves out plankton as it is pumped through the animals body. The larvaceans surround their bodies with a thin gelatinous ‘house’ which is periodically shed as the animal grows. <br />
<br />
[[Image:Pyrosoma.jpg|thumb|left|400px|''The giant colonial tunicate'' Pyrosoma sp. ''Image taken by D. Shale, provided courtesy of MAR-ECO <ref name = "MAR-ECO"> MAR-ECO: http://www.mar-eco.no/</ref>.'']]<br />
<br />
'''Chaetognaths'''<br />
<br />
The chaetognaths (L. ''chaeta'', a bristle; Gk. ''gnathos'', jaw) are a particularly interesting group of zooplankton. They are commonly known as the ‘arrow-worms’ because of their slender arrow-like nature. Every ocean of the world contains a chaetognath representative, and they are typically amongst the commonest animals encountered in the plankton. Arrow worms are voracious predators, with curved bristles that act as powerful jaws. They hunt by remaining motionless in the water until an unsuspecting copepod moves within striking distance; then they dart forward and grasp their prey. It is easy to overlook arrow worms in live plankton samples because they are almost completely transparent, often only becoming visible when they move.<br />
<br />
=== '''Oceanic recycling''' ===<br />
Some of the organic molecules produced by phytoplankton are exuded as dissolved organic matter (DOM). Similarly, DOM is released due to ‘sloppy feeding’ as zooplankton graze on phytoplankton cells. Each millilitre of seawater contains approximately 1 million bacterial cells, many of which utilise DOM as a source of energy and nutrition. The abundance of these bacteria is, to a large extent, regulated by the grazing effects of heterotrophic nano-flagellates (2 – 20 μm in diameter). In turn, the heterotrophic nanoflagellates are grazed by larger heterotrophic organisms such as dinoflagellates and ciliates. Thus, DOM released by primary producers is channelled back into the food chain by what is known as the ‘microbial loop’.<br />
<br />
<br />
===''' Sampling the plankton'''===<br />
<br />
All planktonic organisms were traditionally sampled with a fine-mesh net, the exact size and nature of which depending on the target organisms. Silk, such as the ‘bolting cloths’ originally used by millers to sieve flour, was used for net manufacture prior to the advent of nylon meshes. Plankton nets are typically conical in shape. They are towed or hauled through the water, funnelling organisms towards the ‘cod end’ where they remain trapped.<br />
<br />
==== Phytoplankton ====<br />
Contemporary studies interested in the vertical distribution of [[phytoplankton]] species typically collect seawater samples with Niskin bottles. The constituent [[phytoplankton]] cells are subsequently preserved with Lugol’s iodine for later examination with a microscope. The chlorophyll content of seawater is frequently used as an indicator of [[phytoplankton]] abundance and biomass. Broad-scale (km) surveys of chlorophyll can be achieved by towing a fluorimeter through the water. The colour of the surface of our oceans can now be accurately measured from space <ref name = "Ocean Colour"> Ocean Colour: http://disc.gsfc.nasa.gov/oceancolor/index.shtml</ref>. These ‘ocean colour’ measurements enable global-scale monitoring phytoplankton growth patterns.<br />
<br />
[[Image:cprroutes.jpg|thumb|left|400px|''The map above shows the full network of routes that have been towed over the last 75 years, each with two letter route ID. Image reproduced with permission from SAHFOS7.'']]<br />
<br />
==== Zooplankton ====<br />
Modern biological oceanographers have a suite of nets and sampling arrays to help them collect and count [[zooplankton]] from discrete depths of the ocean. Broad-scale surveys can be undertaken by towing an optical plankton counter (OPC) behind a research vessel. [[Zooplankton]] are funnelled into a narrow corridor and through a beam of light. A computer counts the number of times that the beam of light is broken, and thus the number of zooplankton. The larger types of [[zooplankton]] reflect sound and can thus be surveyed by using acoustic techniques. This type of survey uses techniques identical to those used by fishermen to locate fish. <br />
<br />
The development of the [[Continuous Plankton Recorder (CPR)]], by Sir Alistair Hardy and colleagues in the 1920’s and 30’s, represents one of the major milestones in plankton biogeography <ref name = "SAHFOS"> SAHFOS: http://www.sahfos.ac.uk/</ref>. Each CPR is a self-contained sampling device that collects animals on to an array of ‘silks’. They are designed to be deployed by merchant ships crossing the oceans. This enables a far greater number of observations than would be achievable using dedicated research vessels alone. The CPR survey, which now spans 75 years, has revolutionised our understanding of the distribution and seasonality of plankton.<br />
<br />
==References==<br />
<references/><br />
<br />
<br />
{{author<br />
|AuthorID=19134<br />
|AuthorFullName=Mayor, Daniel<br />
|AuthorName=Daniel}}</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Lessons_learned_from_ICZM_in_Belgium,_The_Netherlands_and_the_United_Kingdom&diff=30646
Lessons learned from ICZM in Belgium, The Netherlands and the United Kingdom
2009-07-09T13:06:27Z
<p>Wouter Kreiken: /* External Links */</p>
<hr />
<div>==Background==<br />
The European Parliament and Council released in 2002 the recommendation ‘2002/413/EC’<ref>European Parliament and Council, 2002. Recommendation of the European Parliament and of the Council of 30 May 2002 concerning the implementation of Integrated Coastal Zone Management (ICZM). 2002/413/EC, Brussels.</ref> to develop and implement Integrated Coastal Zone Management (ICZM) in Europe. All EU member states were requested to develop national ICZM strategies until 2006. The response of the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (‘Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit’; BMU) has been to publish an ICZM strategy in March 2006<ref name="b">BMU, 2006. Integriertes Küstenzonenmanagement in Deutschland. Nationale Strategie für ein integriertes Küstenzonenmanagement (Bestandsaufnahme, Stand 2006), BMU, Bonn, pp. 99.</ref>. But the ICZM process in Germany still contains significant [[Guidelines for Integrated Coastal Zone Management (ICZM) in Germany#Result 1: Gaps of the German ICZM process|gaps]]. In particular, it is not clarified adequately how to implement formally ICZM in the German legal system. <br />
<br />
==Objective==<br />
The objective of this study was to analyse three other European ICZM processes (Belgium, the Netherlands and the United Kingdom) to derive lessons learned for ICZM in Germany in order to reduce or eliminate the [[Guidelines for Integrated Coastal Zone Management (ICZM) in Germany#Result 1: Gaps of the German ICZM process|gaps identified in the German ICZM process]].<br />
<br />
==Research questions==<br />
What are the lessons to be learned concerning formal implementation from the ICZM strategies of three other EU member states, namely Belgium, the Netherlands, and the United Kingdom?<br />
:*a) Where and how is ICZM formally implemented in the particular country? Are the principles of ICZM integrated in existing structures, initiatives, and networks?<br />
:*b) Which institution/person is responsible for ICZM? What are their tasks?<br />
<br />
[[image:lessons1.jpg|thumb|450px|left|Figure 1: Localisation of European countries taken into account to derive lessons learned for the ICZM process in Germany.]]<br />
<br />
==Research methods==<br />
First, lessons learned are defined on the basis of Secchi (1999<ref>Secchi, P., 1999. Proceedings of Alerts and Lessons Learned: An Effective way to prevent failures and problems. Technical Report WPP-167, Noordwijk, pp. 57-61.</ref>), whereupon a “lesson learned is knowledge or understanding gained by experience. (…) A lesson must be significant in that it has a real or assumed impact on operations; valid in that is factually and technically correct; and applicable in that it identifies a specific design, process, or decision that reduces or eliminates the potential for failures and mishaps, or reinforces a positive result”. <br />
<br />
Second, these lessons learned were drawn according to the classification of Rose (1991<ref>Rose, R., 1991. What is lesson-drawing? Journal of Public Policy, 11(1): 3-30.</ref>). He has identified five ways of lesson drawing: “copying” (more or less intact adoption of a programme), “emulation” (adoption with adjustment for different circumstances), “hybridization” (combining elements of programmes from two different places), “synthesis” (combining familiar elements from programmes in effect in three or more places), or “inspiration” (programmes elsewhere used as an intellectual stimulus for developing a novel programme without an analogue elsewhere).<br />
<br />
==Lessons learned from the European context==<br />
<br />
Below, the current ICZM situation of Belgium, The Netherlands and the United is presented. Thereupon, the lessons learned for the German ICZM process are displayed according to the research questions mentioned above.<br />
<br />
<br />
:* [[Analysis of the ICZM process in Belgium]]<br />
:* [[Analysis of the ICZM process in The Netherlands]]<br />
:* [[Analysis of the ICZM process in the United Kingdom]]<br />
<br />
==Conclusion==<br />
Concerning formal implementation, the priority approach of the Netherlands is worth to mention for the German ICZM process. It stands for the priority of flood safety measures at the Dutch coast, at which other coastal interests have to follow by integrating them in flood safety measures. Therewith, ICZM becomes a practicable management tool that can be integrated in flood safety measures.<br />
Referring to responsibilities and tasks, the Coordination Point of Belgium, and the Dutch philosophy of decentralisation are good examples how responsibilities of ICZM are divided. Overall, the trend is giving as much responsibility as possible to the regions. The Belgium Coastal Barometer constitutes a simple set of indicators for sustainable development of the coast. Therewith, it can make a contribution to the German ICZM process where “simple” indicators are needed (BMU, 2006<ref name="b"/>). The lessons learned from the United Kingdom refer to the issue of participation. Coastal Forums have a great potency for networking, keeping up-to-date, exchanging information and raising issues for discussion, but often suffering from the phenomenon of ‘consultation fatigue’. The principle of early participation holds potential for Germany since it seems to be an adequate tools to ensure that stakeholders are formally and early involved in ICZM processes.<br />
<br />
==References==<br />
<references/><br />
<br />
==See also==<br />
<br />
===Internal Links===<br />
* [[Analysis of the ICZM process in Belgium]]<br />
* [[Analysis of the ICZM process in The Netherlands]]<br />
* [[Analysis of the ICZM process in the United Kingdom]]<br />
* [[Lessons learned from three ICZM best-practice projects]]<br />
* [[ICZM-Best practice case study in the Oder estuary]]<br />
* [[ICZM-Best practice case study in the Bay of Lübeck]]<br />
* [[ICZM-Best practice case study in Western Zeelandic-Flanders]]<br />
* [[Guidelines for Integrated Coastal Zone Management (ICZM) in Germany]]<br />
<br />
<br />
<br />
===External Links===<br />
* The present study was performed within the frame of a Diploma thesis at the Technical University Berlin which was published as ICZM-Odra report no. 44, ISSN 1614-5968 [http://www.ikzm-oder.de/en/dokumente.php?dokid=332 download]<br />
<br />
<br />
{{author<br />
|AuthorID=15709<br />
|AuthorFullName=Tim Nandelstaedt<br />
|AuthorName=Tim Nandelstaedt}}<br />
<br />
[[category:Coastal management]]<br />
[[Category:Evaluation and assessment in coastal management]]<br />
[[Category:Policy and decision making in coastal management]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Thermohaline_circulation_of_the_oceans&diff=30515
Thermohaline circulation of the oceans
2009-07-08T15:17:59Z
<p>Wouter Kreiken: </p>
<hr />
<div>{{featured}}<br />
<br />
==Introduction==<br />
<br />
The Thermohaline Circulation (THC) also referred to as the “Great Ocean Conveyor” or the Meridional Overturning Circulation (MOC), can be defined as the density-impelled circulation of the oceans. Thermohaline is derived from the Greek: thermo- for heat and -haline for salt, which constitute the density of water. The water masses transport both energy (heat) and matter (solids, dissolved substances and gasses) around the globe. Changes in the Thermohaline Circulation alter the global ocean heat transport and affect the global climate.(Broecker, W., 1991<ref>Broecker, W., 1991. The great ocean conveyor. Oceanography 1, 79–89.</ref>)<br />
<br />
==Functioning of the Thermahaline Circulation (THC)==<br />
<br />
The conveyor belt (Fig.1) has its start near Greenland and Iceland in the North Atlantic, where seawater at the surface of the ocean is intensively cooled by means of a wind-driven process called evaporative cooling. Only the pure water molecules are removed during evaporation, resulting in an increase in the salinity of the seawater and therefore an increase in the density of the water mass. Evaporative cooling is predominant in the vicinity of the Norwegian Sea, and the sinking water mass known as the North Atlantic Deep Water (NADW), fills the basin and moves southwards through the crevasses in the submarine sills that connect Greenland, Iceland and Great Britain. From there, it flows very slowly into the deep [[abyssal plain| abyssal plains]] of the Atlantic toward Antarctica where the water mass joins the Antarctic Circumpolar Current. Flow from the Arctic Ocean Basin into the Pacific is blocked by the narrow shallows of the Bering Strait.<br />
<br />
<br />
[[Image:Thermohaline.jpg|thumb|center|400px|Fig.1. The Thermohaline Circulation. Source: IPPC 2001.]]<br />
<br />
<br />
<br />
In the Weddell Sea (Antarctica), the combined effect of evaporative cooling and brine exclusion cause the density of the Antarctic Bottom Water (AABW) to be so high, that it in fact underflows the NADW in the Atlantic Basin. Flow of the AABW into the Pacific is blocked by the Drake Passage between the Antarctic Peninsula and the southernmost tip of South America. Within the Antarctic Circumpolar Current, the AABW and NADW are mixed to create the so-called “Common Water” which flows northward, around Southern Africa where it is split into two routes: one into the Indian Ocean and the other past Australia into the Pacific. In the Indian Ocean, some of the cold and salty water from the Atlantic are refreshed, by means of vertical exchange, with the warmer upper ocean water from the tropical Pacific. Within the Pacific Ocean, the remaining cold water undergoes Haline forcing (net high latitude freshwater gain and low latitude evaporation) and slowly becomes warmer and fresher. The outflow of bottom water makes the sea level of the Atlantic slightly lower than the Pacific. Combined with the difference in salinity, this generates a large flow of warmer upper ocean water from the tropical Pacific to the Indian Ocean through the Indonesian Archipelago to replace the AABW. From there, the water flows up through the South Atlantic towards the tropics. The heated tropical waters of the Atlantic proceed until Greenland, where it once more undergoes evaporative cooling, thereby creating a continuous global thermohaline circulation.<br />
<br />
==Bi-polar characteristic of the Thermahaline Circulation==<br />
<br />
Traditionally, research has been almost exclusively devoted to understanding the sensitivity of the high-latitudinal oceans (especially in the Northern Hemisphere) to freshwater fluxes. These studies have advanced considerably the comprehension of the dynamics and functioning of the North Atlantic Bottom Water (NABW) circulation. In comparison therewith, little is known about the southern sources of deepwater (AABW). It is important to bear in mind that the thermohaline circulation is operated by both deepwater sources, and therefore, the deficit of scientific knowledge limits the complete understanding of decadal to millennial time-scale climate change (Seidov, D., 2000<ref name="seidov">Seidov, D., Barron, E., Haupt, B. J., 2000. Meltwater and the global ocean conveyor: northern versus southern connections. Global and Planetary Change 30, 257-270.</ref>). An example of such a deficit is whether the NADW is the ultimate driver of the conveyor, and if additional variability is generated by freshwater impacts in the Southern Ocean (Seidov, D., 2000<ref name="seidov"/>). A significant influence of the Southern Ocean is supported by several scientific lines of evidence. First, many examples of climate intermittency during the glacial cycles of the Pleistocene remain poorly understood, even though they seem to correlate with major deglaciations(Seidov, D., 2000<ref name="seidov"/>). Second, recent studies (Blunier, T. et al. 1998<ref>, 1998. Asynchrony of Antarctic and Greenland climate change during the last glacial period. Nature 394, 739–743.</ref>, Broecker, W.S., 1994<ref>Broecker, W.S., 1994. Massive iceberg discharges as triggers for global climate change. Nature 372, 421–424.</ref>, Stocker, T.F., 1998 <ref>Stocker, T.F., 1998. The seesaw effect. Science 282, 61–62.</ref>) reveal a bi-polar nature of the glacial cycles of the Pleistocene, e.g. the southern Atlantic leads in the occurrence of several Heinrich Events (Vidal, L. et al., 1999<ref>Vidal, L. et al., 1999. Link between the North and South Atlantic during the [[Heinrich events]] of the last glacial period. Clim. Dyn. 15, 909–919.</ref>). Another study (Birchfield, G.E., Broekcer, W.S., 1990<ref name="birchfield">Birchfield, G.E., Broecker, W.S., 1990. A salt oscillator in the glacial Atlantic? 2. A scale analysis model. Paleoceanography 5, 835–843.</ref>) argues that the Little Ice Age (circa 500 years ago) was caused by far stronger deep ocean ventilation in the Southern Ocean. One reason put forward for enhanced southern ocean ventilation is an increase in Atlantic Ocean salinity. Conversely, a slowdown in ventilation could be caused by reduced surface salinity, associated warming, and sea ice or ice sheet melting in the Southern Ocean after the Little Ice Age(Seidov, D., 2000<ref name="seidov"/>, Broecker, W.S., 2000<ref>Broecker, W.S., 2000. Was a change in thermohaline circulation responsible for the Little Ice Age? Proc. Natl. Acad. Sci. 97 (4), 1339–1342.</ref>). The potential importance of feedbacks between the northern and southern sources of deepwater is still largely unknown.<br />
<br />
==Freshwater sources in the Southern Ocean==<br />
<br />
The source and the character of the freshwater sources in the Southern Hemisphere are different from the Northern Hemisphere. Sea surface salinity (SSS) controls both the Antarctic Bottom Water and Antarctic Intermediate Water northward incursions. The SSS can either be increased due to brine exclusion (during the formation of sea ice) or decreased due to sea ice melting. Sea ice formation and brine exclusion rates therefore play a vital role in the southern circulation regime. Additionally, the Antarctic ice sheet has an important function in governing freshwater fluxes into the Southern Ocean. Concern however has been raised about the stability of the West Antarctic Ice Sheet (WAIS). The Antarctic ice sheet mass balance and its possible contribution to global [[sea level rise]] is a major issue of debate, since the potential for changes in freshwater fluxes or salinity variations to influence the Southern Ocean is clearly evident. It has been indicated (Birchfield, G.E., Broekcer, W.S., 1990<ref name="birchfield"/>) that even a relatively small freshwater influx converted to a low-[[salinity]] signal will hamper the effectiveness of the conveyor operation. These factors have initiated a growing modelling effort designed to investigate the climatic role of the Southern Hemisphere (Seidov, D., 2000<ref name="seidov"/>) .<br />
<br />
==The role of global climate change==<br />
<br />
The ocean, including its abyss, is warming at a rate of 0.5˚C or more per century (Levitus, S., 2000<ref>Levitus, S., Antonov, J.I., Boyer, T.P., Stephens, C., 2000. Warming of the world ocean. Science 287, 2225–2229.</ref>). Although historical observations and paleoclimatic data reveal significant climate variability on decadal to millennial time scales, this ocean warming during the last several decades is linked to global climate change. Changes in the atmospheric abundance of greenhouse gases and aerosols, in solar radiation and land surface properties have altered the energy balance of the climate system. <br />
<br />
The global atmospheric concentration of carbon dioxide has increased from a pre-industrial level of 280 parts per million (ppm) to 379 ppm in 2005(Geo Year Book, 2004/2005<ref name="year">Geo Year Book 2004/2005: An overview of our changing environment. United Nations Environment Program. 80-84.</ref>). This atmospheric concentration of carbon dioxide exceeds by far the natural range over the last 650,000 years (180 to 300 ppm)(Geo Year Book, 2004/2005<ref name="year"/>) as determined from ice cores. Consequently, the change of the global energy balance has seen a decrease in sea ice (Fig. 2) as well as rapid ice sheet and permafrost melting. This excess of high latitudinal freshwater influx can substantially modify the deep ocean circulation. <br />
<br />
[[Image:Melting ice sea.jpg|thumb|center|400px|Fig. 2. Melting sea ice]]<br />
<br />
The sinking that drives the thermohaline circulation depends critically on the water being sufficiently cold and salty. Therefore, any factor that changes the state of the conditions for circulation, can result in a slow-down of the thermohaline circulation, and thereby dramatically influence the climatic state and driving further [[climate change]]. Observations over recent decades suggest that changes in the factors governing circulation are already occurring (Geo Year Book, 2004/2005<ref name="year"/>). This raises concerns about potential abrupt climate changes in the future. Is a complete shutdown of the thermohaline possible?<br />
<br />
===High Latitudinal Freshwater Influx===<br />
In light of the deficit of the scientific understanding of the thermohaline circulation and the feedback potentials between the two deepwater sources, it is difficult to predict the influence of global climate change on the dynamics of the thermohaline. Even within the scientific realm there is disagreement on the possibility of a complete shutdown of the thermohaline circulation. Given this discrepancy, a simulation experiment was conducted (Seidov, D., 2000<ref name="seidov"/>) to analyse the sensitivity of thermohaline circulation to low-salinity perturbations. In this simulation, the authors set out to demonstrate the degree to which the thermohaline circulation is driven by both the NADW and the AABW, by means of a designed series of simplified freshwater influx events, in which all ocean model parameters are held constant except salinity. The results of the experiments were described for: a North Atlantic freshwater influx, a Southern Ocean freshwater influx, and a combined influx for the North Atlantic and Southern Ocean. <br />
<br />
* The North Atlantic Freshwater Influx<br />
The results of the experiment simulating a low-salinity impact (-2 psu than present) on the North-Atlantic conform to what is already known from previous work, namely that the conveyor is weaker and shallower. Temperature differences between the current conditions and this low-salinity scenario indicate cooling in high latitudes of the Atlantic Ocean. This occurs because the reduced NADW production led to a shallow conveyor and cooler and fresher water than today in these latitudes characterises the deep ocean water. In addition to this, the surface ocean has more time to lose heat to the atmosphere because the overturning slowed. The reduced NADW outflow has an evident imprint in the oceanic heat transport. Northward cross-equatorial heat transport is dramatically reduced in the scenario with a strong freshwater impact, which indicates the possibility of a cold episode following a freshwater influx event. If the present-day global warming was potent enough to induce a low-salinity episode in the North Atlantic, caused by iceberg and Arctic sea ice melting, the result could be a tendency towards colder temperature conditions in the Northern Hemisphere. It is important though to note that even with an excessive northern low-salinity signal of -2 psu during the simulation, no complete termination of the conveyor occurred.<br />
<br />
* The Southern Ocean Freshwater Influx<br />
In contrast to the predictable results of the northern low-salinity impact, the results of the Southern Ocean surface freshening are less intuitive. Two aspects are noteworthy: first the circulation changes driven by the low-salinity signal were much stronger, and second, they led to a very strong warming of the deep ocean. Warming takes place over the entire deep ocean and its maximum shifts to the southern edges. This deep-sea warming is caused not only by a substantial increase (by 40-60%) in NADW production, but also because the meridional overturning takes over the entire deep ocean, pushing away the lessened AABW. In the North Atlantic scenario, the freshwater influx impact on the conveyor caused thermal effects only in the deep Atlantic Ocean, whereas in the Southern Ocean, the freshwater scenarios impact is global. The increased NADW outflow in the deep layers leads to increased compensating northward surface water flow. This flow carries more warm and salty subtropical water to convection sites, which might further increase NADW production until the atmosphere warms up to reduce the cooling of the sea surface and subsequently reduce the deep convection. The positive feedback of NADW production and northward heat transport can be viewed as a first link toward high-latitudinal warming in the Northern Hemisphere caused by freshwater influx events in the Southern Ocean.<br />
<br />
* Combined Influx for the North Atlantic and Southern Ocean<br />
The results of a combined low-salinity event of the North Atlantic and the Southern Ocean, display a deepwater regime that is qualitatively similar to a Southern-Ocean-only experiment. Less Deep Ocean warming is observed, however the impact still remains global and substantial. Results of the runs with perturbations to two sources, demonstrates a more powerful response to a freshwater influx event in the Southern Ocean than for those in the North Atlantic. However, much of this power stems from increased NADW production.<br />
<br />
===Sea-Level Change===<br />
[[Sea level rise]] can be caused by either melting of major ice sheets (Fig. 3), or as an indirect effect by freshwater influx events caused by thermal restructuring of the world ocean. As the deep ocean warms up, the sea elevation will change as a result of the thermal expansion of sea water. Historic [http://en.wikipedia.org/wiki/Hydrography hydrographic] data suggest that thermal expansion of the ocean can contribute tens of centimeters to the observed [[sea level rise]] over the last century (Godfrey, J.S., Love, G., 1992<ref>Godfrey, J.S., Love, G., 1992. Assessment of sealevel rise, specific to the South Asian and Australian situations. Seal Level Changes: Determination and Effects. Geophys. Monogr., vol. 69. AGU, Washington, DC, pp. 87–94. </ref>). Some simulations (Church, J.A., Godfrey, J.S., Jacket, D.R., McDougall, T.R., 1991<ref>Church, J.A., Godfrey, J.S., Jacket, D.R., McDougall, T.R., 1991. A model of sealevel rise caused by ocean thermal expansion. J. Clim. 4, 438–456.</ref> indicate that the thermal expansion of the ocean associated with a global warming of 3˚C temperature rise by the year 2050 results in up to 30 cm sea-level rise. In the simulation experiment conducted, (Seidov, D., 2000<ref name="seidov"/>) a significant sea-level rise of approximately 2-3 meter may occur during a Southern Ocean event (Fig. 4). In many sensitive coastal areas the sea-level rise could be over 1 meter. It is important to note that this sea-level rise could occur without significant melting of the ice sheets, including WAIS, which is considered the most vulnerable to climate change(Seidov, D., 2000<ref name="seidov"/>).<br />
<br />
[[Image:Figure_3.jpg|thumb|center|400px|Fig.3. IPCC summary of the observed variations in the cryosphere for the years 1993-2003 <ref>Lemke, P., J. Ren, R.B. Alley, I. Allison, J. Carrasco, G. Flato, Y. Fujii, G. Kaser, P. Mote, R.H. Thomas and T. Zhang, 2007: Observations: Changes in Snow, Ice and Frozen Ground. In: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, US, Pp. 375 </ref>]]<br />
<br />
[[Image:Differences.jpg|thumb|center|400px|Fig. 4: Differences of the sea-level elevations in cm relative to the current situation and a freshwater influx event in the North Atlantic and the Southern Ocean(Seidov, D., 2000<ref name="seidov"/>)]]<br />
<br />
===Indirect Impacts Resulting from Changes in the Thermohaline Circulation===<br />
The changing climatic conditions and the increased freshwater influx in the Polar Regions have seen sea ice retreats from the coastline of Arctic countries by between 150 km and 200 km. According to the [http://www.ipcc.ch/ International Panel on Climate Change] (IPCC), by 2050 the sea ice might retreat up to 800 km as a result of global warming. The loss of ice in the Polar Regions could lead to a sudden acceleration of global warming, as ice reflects radiation or heat from the sun back into space. The absence of sea ice combined with deep ocean warming will see more evaporation and rainfall occurring in these sensitive regions, which in turn will speed up sea ice loss.<br />
<br />
The retreat and loss of sea ice in the Polar Regions will also have a harmful impact on the many species living in the regions. Polar bears, for example, need ice so that they can hunt for seals. A loss of sea ice could make it harder for these animals to acquire enough food. Pregnant females and those with cubs may be particularly at risk. The species of seal that need ice for resting or pup rearing will also be at risk.<br />
<br />
As mentioned above, the change of the thermohaline circulation is expected to alter the speed and patterns of [[ocean currents]], which in turn will impact [[fish stocks]]. According to the [http://www.ipcc.ch/ipccreports/assessments-reports.htm Third Assessment Report] of the [http://www.ipcc.ch/ IPCC]: “Arctic fisheries are among the most productive in the world. Changes in the velocity and direction of ocean currents affect the availability of [[nutrients]] and the disposition of larval and juvenile organisms, thereby influencing recruitment, growth and mortality.” Changes in the fish stocks are already taking place, with the result that some stocks are boosting while others are damaged. For example, Groundfish stocks have shown a positive response to recent climate change, while the thermally sensitive Greenland turbot and King crab stocks in the eastern Bering Sea and Kodiak are declining. The IPCC anticipate that harvests might halve or double depending on the stocks concerned; meanwhile some fisheries might die out altogether while new ones develop. This could increase or decrease local economies by hundreds of millions of dollars annually (IPCC). These projected changes in the [[abundance]] and [[distribution]] of fish stocks and wildlife are just one of the issues facing fishermen, Arctic communities and the indigenous people. <br />
<br />
The Polar Regions annually accumulates pollution, including [[Theme_4_State_of_the_art#Persistent_organic_pollutants|Persistent Organic Pollutants]] (POPs), which have been discharged from industry and agriculture around the globe. Melting of the sea ice could trigger the release of these pollutants which could cause them to re-enter the food chain. This would pose a health threat to top predators, e.g. polar bears and humans in these regions.<br />
<br />
On the other hand, the melting of sea ice could have one economic benefit, namely in the area of shipping. The northwards retreat of sea ice opens up the Northern Sea Route, which would allow vessels to sail from Europe to the Far East by going north of Russia rather than using the existing route, i.e. the Suez Canal. Although this should reduce sailing times, cutting the costs of goods and air pollution, the risk of accidents leading to oil spills still remains.<br />
<br />
==Overview of impacts for coastal regions==<br />
<br />
The major impact for coastal regions caused by a change in the thermohaline circulation will be rising sea levels. There are many coastal sensitive regions around the globe which will be affected by even a small change in the sea level. As indicated above, the changing circulation can rise sea levels by either: melting of sea ice and ice sheets in the Polar Regions or via thermal expansion of the sea water. In 2007 approximately 634 million people lived in coastal areas within 9.1m of the sea level. Two thirds of the world’s cities with more than five million people are located in these low-lying coastal areas. <br />
<br />
The IPCC Working Group II report indicates that current and future climate change would be expected to have a number of impacts, especially on coastal systems. Potential impacts may include: increased [[coastal erosion]], higher [[storm surge]] flooding, inhibition of [[primary production]] processes, more extensive coastal inundation, changes in surface water quality and groundwater characteristics, increased loss of property and coastal habitats, increased [[flood risk]] and potential loss of life, loss of non-monetary cultural resources and values, impacts on agriculture and aquaculture via a decline in soil and water quality, and loss of tourism, recreation and transportation functions. Furthermore the IPCC report concludes that due to the great diversity of coastal environments; regional and local differences in projected relative sea level and climate changes; and differences in the [[resilience]] and [[adaptive capacity]] of [[ecosystems]], sectors and countries, the impacts will be highly variable in time and space and will not necessarily be negative in all situations.<br />
<br />
==See also==<br />
<br />
===Internal Links===<br />
*[[Ocean circulation]]<br />
<br />
===External Links===<br />
* Wikipedia: http://en.wikipedia.org/wiki/Thermohaline_circulation<br />
* Ocean Motion and Surface Currents: http://oceanmotion.org/index.htm<br />
* IPPC: http://www.ipcc.ch/<br />
* UNEP: http://unep.org<br />
* GEO Year Book: http://www.unep.org/geo/yearbook<br />
<br />
==References==<br />
<references/><br />
<br />
<br />
{{author<br />
|AuthorID=16609<br />
|AuthorFullName=Tange, Hannli<br />
|AuthorName=Tange, Hannli}}<br />
[[Category: Theme 5]]<br />
[[Category: Coastal processes, interactions and resources]]<br />
[[Category: Hydrodynamics]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Main_Page&diff=30514
Main Page
2009-07-08T15:16:42Z
<p>Wouter Kreiken: </p>
<hr />
<div><!----------------------------Introduction-----------------><br />
{| style="width:100%; border:2px solid #23297A; margin:0em 0em 1em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
|align="top"|<br />
<div style="font-size:100%; padding-bottom:0.15em;">Welcome to the [[Coastal Wiki|Coastal and Marine Wiki]], an Internet encyclopaedia of [[Special:Statistics|{{NUMBEROFARTICLES}}]] information pages for and by coastal professionals providing up-to-date high quality Coastal and Marine information. [[Coastal Wiki:Why, What and for Whom?|More about the Coastal and Marine Wiki]]</div><br />
|}<br />
<!----------------------End of introduction-----------------><br />
<br />
<!-----------------------Today's featured article, Did you know--------------------><br />
{|style="border-spacing:8px; margin:0px -8px;"<br />
|class="MainPageBG" style="width:70%; border:1px solid #23297A; background:#f5faff; vertical-align:top; color:#000;"|<br />
{|width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">This months featured article</h2><br />
|-<br />
|style="color:#000;"| <br />
<br />
{{Template:This_weeks_featured_article}} [[Thermohaline circulation of the oceans|'''More..''']]<br />
<br />
|-<br />
! <br />
|-<br />
|}<!----------------------------------Categories---------------------><br />
|class="MainPageBG" style="width:30%; border:1px solid #23297A; background:#f5faff; vertical-align:top"|<br />
{| width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
!<br />
<br />
<h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">Categories</h2><br />
|-<br />
|-<br />
|style="width:15em; vertical-align:right; font-weight:bold;"|<br />
[[Image:natural_bis.gif|natural.gif]] [[:Category:Coastal and marine natural environment|Natural environment]]<br><br><br />
[[Image:human_bis.gif|human4.gif]] [[:Category:Coastal and marine human activities|Human activities]]<br><br><br />
[[Image:impacts_bis.gif|impacts.gif]] [[:Category:Coastal and marine issues and impacts|Issues and impacts]]<br><br><br />
[[Image:earth_bis.gif|earth2.gif]] [[:Category:Coastal and marine areas and locations|Areas and locations]]<br><br><br />
[[Image:management-bis.gif|Management.gif]] [[:Category:Coastal management|Coastal management]]<br><br><br />
[[Image:people_bis.gif|people.gif]] [[:Category:People and organisations in coastal management|People and organisations ]] <br />
|}<br />
|}<br />
{{#categorytree:Coastal and marine system|mode=pages|onlyroot=on|style=border:1px solid gray; padding:0.7ex; vertical-align:right; background-color:#f5faff;}}<br />
<br><br />
'''Welcome to the Coastal Wiki, your guide to coastal knowledge and experience'''<br><br />
You may find information on any coastal topic by entering a corresponding term in the search window. “Go” will direct you to an article with this title (if such an article exists); “Search” will provide an overview of articles in which your search term appears. You will find an explanation of coastal terms and concepts in the [[Glossary]].<br />
<br />
We also invite coastal and marine practitioners, policymakers and scientists to make a contribution to this new concept in sharing European knowledge and experience in integrated coastal zone management. You may contribute in several ways: you may improve or update an existing article, you may add a discussion page to an existing article or you may add a new topic.<br />
<br><br><br />
<br />
'''How to contribute to the Coastal Wiki'''<br><br />
You have unrestricted access to the Coastal Wiki. But for adding or editing articles an authorisation is required. This is a major difference with the general wikipedia. For obtaining an editing authorisation you may contact your [http://www.encora.eu/networks.php national coordination office] or you may simply send an email to info@encora.eu. You will receive a request to provide contact information for the Wiki Contact Database. Anonymous contributions to the Coastal Wiki are precluded. Authors, co-authors and editors of articles are explicitly acknowledged. Your contribution will be reviewed by the coordinator of the theme where your article best fits. The theme coordinators also check that your contribution is [[links|adequately linked]] to existing articles on similar or related topics. <br />
<br />
You should remember that the Coastal Wiki is primarily meant for disseminating knowledge to a broader audience than the circles of specialists working at the frontiers of science. It is not meant for publishing original research; it is a vehicle for disseminating knowledge complementary to the traditional peer-reviewed scientific journals. Please read the [[Basic setup, rules and guidelines]] and [[How to edit an article]] before you start writing an article.<br />
<br><br><br />
<!------------------------------10 themes-----------------><br />
{|border=1 style="border:2px #23297A solid; background:#f5faff;" width="688px" cellspacing="0" cellpadding="0" <br />
|cellspacing="0" style="border-bottom:1px solid #23297A; background:#cee0f2; font-size:150%" colspan=2 align=center height=30px|Encora Themes<br />
|-<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign="top" style="border-right:1px solid #23297A"|[[Image:Theme01_40.png|Theme 1 : Social and economic aspects of ICZM Multifunctionality and Valuation.]]||<br />
'''[[Theme 1]] - Social and economic aspects of ICZM Multifunctionality and Valuation.'''<br><br />
Valuation of competing functions to optimise the societal use of coastal and marine resources.<br />
|}<br />
<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme02_40.png|Theme 2 : ICZM Participation and Implementation.]]||<br />
'''[[Theme 2]] - ICZM Participation and Implementation.''' <br><br />
Testing and improving methods to evaluate progress in the implementation of ICZM, including eGovernance. <br><br />
|}<br />
|-<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme03_40.png|Theme 3 : Coastal and marine spatial planning.]]||<br />
'''[[Theme 3]] - Coastal and marine spatial planning.''' <br><br />
Multiple-scale structuring of spatial coastal and marine planning and related decision-support systems for sustainable development. <br><br />
|}<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="102px" valign=center style="border-right:1px solid #23297A"|[[Image:Theme04_40.png|Theme 4 : Pollution, prevention and mitigation.]]||<br />
'''[[Theme 4]] - Pollution, prevention and mitigation.''' <br><br />
Development and application of emerging methodologies for preventing, detecting and mitigating pollution and for identification of areas at risk. <br><br />
|}<br />
|-<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme05_40.png|Theme 5 : Long-term geomorphological change and climate impacts.]]||<br />
'''[[Theme 5]] - Long-term geomorphological change and climate impacts.'''<br><br />
Promoting development, demonstration & dissemination of new and emerging models & methodologies for prediction of changes to coastal systems.<br><br />
|}<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme06_40.png| Theme 6 : Effect of development and use on eco-morphology and coastal habitats.]]||<br />
'''[[Theme 6]] - Effect of development and use on eco-morphology and coastal habitats.'''<br><br />
Impact-assessment tools and environmental techniques for recovery of coastal habitats.<br><br />
|}<br />
|-<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme07_40.png|Theme 7|Theme 7 Biodiversity of coastal and marine habitats and ecosystems]]||<br />
'''[[Theme 7 Biodiversity of coastal and marine habitats and ecosystems|Theme 7]] - Assessment of biodiversity change.''' <br><br />
Testing and improving an ecological valuation protocol for the coastal and marine environment, including transitional waters. <br><br />
|}<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme08_40.png|Theme 8 : New sustainable coastal engineering techniques.]]||<br />
'''[[Theme 8]] - New sustainable coastal engineering techniques.''' <br><br />
Cataloguing innovative coastal engineering techniques to solve practical coastal protection issues. <br><br />
|}<br />
|-<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme09_40.png|Theme 9 : Assessment of field observation techniques.]]||<br />
'''[[Theme 9]] - Assessment of field observation techniques.''' <br><br />
New and emerging tools and practices for coastal and marine observation, with focus on remote sensing and remotely controlled measuring devices. <br><br />
|}<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme10_40.png| Theme 10 : Capacity Building, Training and Education.]]||<br />
'''[[Theme 10]] - Capacity Building, Training and Education. ''' <br><br />
Comparative assessment of ICZM training and education programmes. <br><br />
|}<br />
|}<br />
<!------------------------------end of 10 themes-----------------><br />
<br><br />
<!------------------------------Bottom table---------------------><br />
{| style=" width:100%; border:1px solid #23297A; margin:0em 0em 1em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
<br />
|style="width:25%"| [[Help:Contents|'''Help pages''']] <br />
|style="width:25%"|[[glossary|'''Glossary''']] <br />
|style="width:25%"| [[Special:Popularpages|'''Popular pages''']] <br />
|style="width:25%" align="right"| [[Articles that need expanding|'''Articles that need expanding''']]<br />
<br />
|}<br />
<!------------------------------end of Bottom table---------------------></div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Template:This_weeks_featured_article&diff=30513
Template:This weeks featured article
2009-07-08T15:15:38Z
<p>Wouter Kreiken: /* Thermohaline circulation of the oceans */</p>
<hr />
<div>==Thermohaline circulation of the oceans==<br />
<br />
[[Image:Thermohaline.jpg|thumb|right|350px|Fig.1. The Thermohaline Circulation. Source: IPPC 2001.]]<br />
<br />
The Thermohaline Circulation (THC) also referred to as the “Great Ocean Conveyor” or the Meridional Overturning Circulation (MOC), can be defined as the density-impelled circulation of the oceans. Thermohaline is derived from the Greek: thermo- for heat and -haline for salt, which constitute the density of water. The water masses transport both energy (heat) and matter (solids, dissolved substances and gasses) around the globe. Changes in the Thermohaline Circulation alter the global ocean heat transport and affect the global climate.(Broecker, W., 1991<ref>Broecker, W., 1991. The great ocean conveyor. Oceanography 1, 79–89.</ref>)</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Template:This_weeks_featured_article&diff=30512
Template:This weeks featured article
2009-07-08T15:15:05Z
<p>Wouter Kreiken: Thermohaline circulation of the oceans</p>
<hr />
<div>==Thermohaline circulation of the oceans==<br />
<br />
[[Image:Thermohaline.jpg|thumb|center|400px|Fig.1. The Thermohaline Circulation. Source: IPPC 2001.]]<br />
<br />
The Thermohaline Circulation (THC) also referred to as the “Great Ocean Conveyor” or the Meridional Overturning Circulation (MOC), can be defined as the density-impelled circulation of the oceans. Thermohaline is derived from the Greek: thermo- for heat and -haline for salt, which constitute the density of water. The water masses transport both energy (heat) and matter (solids, dissolved substances and gasses) around the globe. Changes in the Thermohaline Circulation alter the global ocean heat transport and affect the global climate.(Broecker, W., 1991<ref>Broecker, W., 1991. The great ocean conveyor. Oceanography 1, 79–89.</ref>)</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Template:This_weeks_featured_article&diff=28752
Template:This weeks featured article
2009-04-01T09:47:48Z
<p>Wouter Kreiken: /* Tampa Bay Estuary Program */</p>
<hr />
<div>==Tampa Bay Estuary Program==<br />
<br />
[[Image:The Social Network for Tampa Bay.jpg|thumb|300px|right|Figure 1: The Social Network for Tampa Bay <ref>http://www.buzzardsbay.org/download/nep-networks-paper.pdf</ref>]]<br />
<br />
In 1990, Tampa Bay was designated an "estuary of national significance" by the US Congress, and joined the ranks of the [http://www.epa.gov/nep/| National Estuary Program] (which currently contains 28 estuaries) in 1991. As an urban watershed confronted with pollution, habitat loss and increasing development, the [http://www.tbep.org/| Tampa Bay Estuary Program (TBEP)] faced significant challenges. Over fifteen years later, TBEP stands as a model for collaborative partnerships, innovative agreements and approaches for habitat restoration and addressing [[nitrogen| atmospheric nitrogen]] deposition as a contributor to [[eutrophication]]. <br />
<br />
Tampa Bay is Florida’s largest open-water estuary, spanning 400 square miles, with a drainage area nearly six times that size. While the Bay contains rich [[biodiversity]], it is impacted by a rapidly growing human population and the second largest metropolitan area in the state. As of 2008, more than 2.3 million people lived in the watershed, and that number is expected to grow by nearly 20 percent by the year 2015.</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Main_Page&diff=28751
Main Page
2009-04-01T09:47:33Z
<p>Wouter Kreiken: Tampa Bay Estuary Program</p>
<hr />
<div><!----------------------------Introduction-----------------><br />
{| style="width:100%; border:2px solid #23297A; margin:0em 0em 1em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
|align="top"|<br />
<div style="font-size:100%; padding-bottom:0.15em;">Welcome to the [[Coastal Wiki|Coastal and Marine Wiki]], an Internet encyclopaedia of [[Special:Statistics|{{NUMBEROFARTICLES}}]] information pages for and by coastal professionals providing up-to-date high quality Coastal and Marine information. [[Coastal Wiki:Why, What and for Whom?|More about the Coastal and Marine Wiki]]</div><br />
|}<br />
<!----------------------End of introduction-----------------><br />
<br />
<!-----------------------Today's featured article, Did you know--------------------><br />
{|style="border-spacing:8px; margin:0px -8px;"<br />
|class="MainPageBG" style="width:70%; border:1px solid #23297A; background:#f5faff; vertical-align:top; color:#000;"|<br />
{|width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">This months featured article</h2><br />
|-<br />
|style="color:#000;"| <br />
<br />
{{Template:This_weeks_featured_article}} [[Tampa Bay Estuary Program|'''More..''']]<br />
<br />
|-<br />
! <br />
|-<br />
|}<!----------------------------------Categories---------------------><br />
|class="MainPageBG" style="width:30%; border:1px solid #23297A; background:#f5faff; vertical-align:top"|<br />
{| width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
!<br />
<br />
<h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">Categories</h2><br />
|-<br />
|-<br />
|style="width:15em; vertical-align:right; font-weight:bold;"|<br />
[[Image:natural_bis.gif|natural.gif]] [[:Category:Coastal and marine natural environment|Natural environment]]<br><br><br />
[[Image:human_bis.gif|human4.gif]] [[:Category:Coastal and marine human activities|Human activities]]<br><br><br />
[[Image:impacts_bis.gif|impacts.gif]] [[:Category:Coastal and marine issues and impacts|Issues and impacts]]<br><br><br />
[[Image:earth_bis.gif|earth2.gif]] [[:Category:Coastal and marine areas and locations|Areas and locations]]<br><br><br />
[[Image:management-bis.gif|Management.gif]] [[:Category:Coastal management|Coastal management]]<br><br><br />
[[Image:people_bis.gif|people.gif]] [[:Category:People and organisations in coastal management|People and organisations ]] <br />
|}<br />
|}<br />
{{#categorytree:Coastal and marine system|mode=pages|onlyroot=on|style=border:1px solid gray; padding:0.7ex; vertical-align:right; background-color:#f5faff;}}<br />
<br><br />
'''Welcome to the Coastal Wiki, your guide to coastal knowledge and experience'''<br><br />
You may find information on any coastal topic by entering a corresponding term in the search window. “Go” will direct you to an article with this title (if such an article exists); “Search” will provide an overview of articles in which your search term appears. You will find an explanation of coastal terms and concepts in the [[Glossary]].<br />
<br />
We also invite coastal and marine practitioners, policymakers and scientists to make a contribution to this new concept in sharing European knowledge and experience in integrated coastal zone management. You may contribute in several ways: you may improve or update an existing article, you may add a discussion page to an existing article or you may add a new topic.<br />
<br><br><br />
<br />
'''How to contribute to the Coastal Wiki'''<br><br />
You have unrestricted access to the Coastal Wiki. But for adding or editing articles an authorisation is required. This is a major difference with the general wikipedia. For obtaining an editing authorisation you may contact your [http://www.encora.eu/networks.php national coordination office] or you may simply send an email to info@encora.eu. You will receive a request to provide contact information for the Wiki Contact Database. Anonymous contributions to the Coastal Wiki are precluded. Authors, co-authors and editors of articles are explicitly acknowledged. Your contribution will be reviewed by the coordinator of the theme where your article best fits. The theme coordinators also check that your contribution is [[links|adequately linked]] to existing articles on similar or related topics. <br />
<br />
You should remember that the Coastal Wiki is primarily meant for disseminating knowledge to a broader audience than the circles of specialists working at the frontiers of science. It is not meant for publishing original research; it is a vehicle for disseminating knowledge complementary to the traditional peer-reviewed scientific journals. Please read the [[Basic setup, rules and guidelines]] and [[How to edit an article]] before you start writing an article.<br />
<br><br><br />
<!------------------------------10 themes-----------------><br />
{|border=1 style="border:2px #23297A solid; background:#f5faff;" width="688px" cellspacing="0" cellpadding="0" <br />
|cellspacing="0" style="border-bottom:1px solid #23297A; background:#cee0f2; font-size:150%" colspan=2 align=center height=30px|Encora Themes<br />
|-<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign="top" style="border-right:1px solid #23297A"|[[Image:Theme01_40.png|Theme 1 : Social and economic aspects of ICZM Multifunctionality and Valuation.]]||<br />
'''[[Theme 1]] - Social and economic aspects of ICZM Multifunctionality and Valuation.'''<br><br />
Valuation of competing functions to optimise the societal use of coastal and marine resources.<br />
|}<br />
<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme02_40.png|Theme 2 : ICZM Participation and Implementation.]]||<br />
'''[[Theme 2]] - ICZM Participation and Implementation.''' <br><br />
Testing and improving methods to evaluate progress in the implementation of ICZM, including eGovernance. <br><br />
|}<br />
|-<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme03_40.png|Theme 3 : Coastal and marine spatial planning.]]||<br />
'''[[Theme 3]] - Coastal and marine spatial planning.''' <br><br />
Multiple-scale structuring of spatial coastal and marine planning and related decision-support systems for sustainable development. <br><br />
|}<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="102px" valign=center style="border-right:1px solid #23297A"|[[Image:Theme04_40.png|Theme 4 : Pollution, prevention and mitigation.]]||<br />
'''[[Theme 4]] - Pollution, prevention and mitigation.''' <br><br />
Development and application of emerging methodologies for preventing, detecting and mitigating pollution and for identification of areas at risk. <br><br />
|}<br />
|-<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme05_40.png|Theme 5 : Long-term geomorphological change and climate impacts.]]||<br />
'''[[Theme 5]] - Long-term geomorphological change and climate impacts.'''<br><br />
Promoting development, demonstration & dissemination of new and emerging models & methodologies for prediction of changes to coastal systems.<br><br />
|}<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme06_40.png| Theme 6 : Effect of development and use on eco-morphology and coastal habitats.]]||<br />
'''[[Theme 6]] - Effect of development and use on eco-morphology and coastal habitats.'''<br><br />
Impact-assessment tools and environmental techniques for recovery of coastal habitats.<br><br />
|}<br />
|-<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme07_40.png|Theme 7|Theme 7 Biodiversity of coastal and marine habitats and ecosystems]]||<br />
'''[[Theme 7 Biodiversity of coastal and marine habitats and ecosystems|Theme 7]] - Assessment of biodiversity change.''' <br><br />
Testing and improving an ecological valuation protocol for the coastal and marine environment, including transitional waters. <br><br />
|}<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme08_40.png|Theme 8 : New sustainable coastal engineering techniques.]]||<br />
'''[[Theme 8]] - New sustainable coastal engineering techniques.''' <br><br />
Cataloguing innovative coastal engineering techniques to solve practical coastal protection issues. <br><br />
|}<br />
|-<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme09_40.png|Theme 9 : Assessment of field observation techniques.]]||<br />
'''[[Theme 9]] - Assessment of field observation techniques.''' <br><br />
New and emerging tools and practices for coastal and marine observation, with focus on remote sensing and remotely controlled measuring devices. <br><br />
|}<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme10_40.png| Theme 10 : Capacity Building, Training and Education.]]||<br />
'''[[Theme 10]] - Capacity Building, Training and Education. ''' <br><br />
Comparative assessment of ICZM training and education programmes. <br><br />
|}<br />
|}<br />
<!------------------------------end of 10 themes-----------------><br />
<br><br />
<!------------------------------Bottom table---------------------><br />
{| style=" width:100%; border:1px solid #23297A; margin:0em 0em 1em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
<br />
|style="width:25%"| [[Help:Contents|'''Help pages''']] <br />
|style="width:25%"|[[glossary|'''Glossary''']] <br />
|style="width:25%"| [[Special:Popularpages|'''Popular pages''']] <br />
|style="width:25%" align="right"| [[Articles that need expanding|'''Articles that need expanding''']]<br />
<br />
|}<br />
<!------------------------------end of Bottom table---------------------></div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Template:This_weeks_featured_article&diff=28750
Template:This weeks featured article
2009-04-01T09:46:58Z
<p>Wouter Kreiken: /* Tampa Bay Estuary Program */</p>
<hr />
<div>==Tampa Bay Estuary Program==<br />
<br />
[[Image:The Social Network for Tampa Bay.jpg|thumb|300px|left|Figure 1: The Social Network for Tampa Bay <ref>http://www.buzzardsbay.org/download/nep-networks-paper.pdf</ref>]]<br />
<br />
In 1990, Tampa Bay was designated an "estuary of national significance" by the US Congress, and joined the ranks of the [http://www.epa.gov/nep/| National Estuary Program] (which currently contains 28 estuaries) in 1991. As an urban watershed confronted with pollution, habitat loss and increasing development, the [http://www.tbep.org/| Tampa Bay Estuary Program (TBEP)] faced significant challenges. Over fifteen years later, TBEP stands as a model for collaborative partnerships, innovative agreements and approaches for habitat restoration and addressing [[nitrogen| atmospheric nitrogen]] deposition as a contributor to [[eutrophication]]. <br />
<br />
Tampa Bay is Florida’s largest open-water estuary, spanning 400 square miles, with a drainage area nearly six times that size. While the Bay contains rich [[biodiversity]], it is impacted by a rapidly growing human population and the second largest metropolitan area in the state. As of 2008, more than 2.3 million people lived in the watershed, and that number is expected to grow by nearly 20 percent by the year 2015.</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Template:This_weeks_featured_article&diff=28749
Template:This weeks featured article
2009-04-01T09:46:42Z
<p>Wouter Kreiken: /* Tampa Bay Estuary Program */</p>
<hr />
<div>==Tampa Bay Estuary Program==<br />
<br />
[[Image:The Social Network for Tampa Bay.jpg|thumb|300px|left|Figure 1: The Social Network for Tampa Bay <ref>http://www.buzzardsbay.org/download/nep-networks-paper.pdf</ref>]]<br />
<br />
In 1990, Tampa Bay was designated an "estuary of national significance" by the US Congress, and joined the ranks of the [http://www.epa.gov/nep/| National Estuary Program] (which currently contains 28 estuaries) in 1991. As an urban watershed confronted with pollution, habitat loss and increasing development, the [http://www.tbep.org/| Tampa Bay Estuary Program (TBEP)] faced significant challenges. Over fifteen years later, TBEP stands as a model for collaborative partnerships, innovative agreements and approaches for habitat restoration and addressing [[nitrogen| atmospheric nitrogen]] deposition as a contributor to [[eutrophication]]. <br />
<br />
Tampa Bay is Florida’s largest open-water estuary, spanning 400 square miles, with a drainage area nearly six times that size. While the Bay contains rich [[biodiversity]], it is impacted by a rapidly growing human population and the second largest metropolitan area in the state. As of 2008, more than 2.3 million people lived in the watershed, and that number is expected to grow by nearly 20 percent by the year 2015. <br />
<br />
In the 1950s, rapid population growth in the Tampa Bay watershed and increased urban development caused a significant deterioration in the bay’s water quality and habitat, and natural resources. Urban development, dredging, canals, and causeways have altered approximately half of the bay’s original shoreline. Forty percent (40%) of the Bay’s seagrass beds have disappeared since 1950, as have 21% of its [[wetlands| emergent wetlands]] (Tampa Bay Estuary Program/TBEP).</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Tampa_Bay_Estuary_Program&diff=28748
Tampa Bay Estuary Program
2009-04-01T09:45:09Z
<p>Wouter Kreiken: </p>
<hr />
<div>{{featured}}<br />
<br />
In 1990, Tampa Bay was designated an "estuary of national significance" by the US Congress, and joined the ranks of the [http://www.epa.gov/nep/| National Estuary Program] (which currently contains 28 estuaries) in 1991. As an urban watershed confronted with pollution, habitat loss and increasing development, the [http://www.tbep.org/| Tampa Bay Estuary Program (TBEP)] faced significant challenges. Over fifteen years later, TBEP stands as a model for collaborative partnerships, innovative agreements and approaches for habitat restoration and addressing [[nitrogen| atmospheric nitrogen]] deposition as a contributor to [[eutrophication]]. <br />
<br />
==Introduction==<br />
Tampa Bay is Florida’s largest open-water estuary, spanning 400 square miles, with a drainage area nearly six times that size. While the Bay contains rich [[biodiversity]], it is impacted by a rapidly growing human population and the second largest metropolitan area in the state. As of 2008, more than 2.3 million people lived in the watershed, and that number is expected to grow by nearly 20 percent by the year 2015. <br />
<br />
In the 1950s, rapid population growth in the Tampa Bay watershed and increased urban development caused a significant deterioration in the bay’s water quality and habitat, and natural resources. Urban development, dredging, canals, and causeways have altered approximately half of the bay’s original shoreline. Forty percent (40%) of the Bay’s seagrass beds have disappeared since 1950, as have 21% of its [[wetlands| emergent wetlands]] (Tampa Bay Estuary Program/TBEP).<br />
<br />
[[Image:The Social Network for Tampa Bay.jpg|thumb|350px|left|Figure 1: The Social Network for Tampa Bay <ref>http://www.buzzardsbay.org/download/nep-networks-paper.pdf</ref>]]<br />
<br />
==History==<br />
There have been multiple efforts to improve water quality in Tampa Bay. The first major study of Tampa Bay’s water quality was conducted by the Federal Water Pollution Control Administration (FWPCA) in 1969. The study’s findings, combined with grass-roots efforts in the early 1970s, led to upgrades in sewage treatment plants and reduced nutrient loadings. Then in 1983, the state established the Tampa Bay Management Study Commission to develop a comprehensive management strategy for the Bay. The regional planning council and the Southwest Florida Water Management District (SWFWMD) were requested to identify the priority problems and develop recommendations and projects to be conducted as part of a Surface Water Improvement and Management (SWIM) plan for Tampa Bay. This was the first organized effort to address water quality issues in the Bay, and it laid the groundwork for entry to the [http://www.epa.gov/nep/| national estuary program (NEP)].<br />
<br />
==Establishment of the Tampa Bay Estuary Program (TBEP)==<br />
The [http://www.tbep.org/| Tampa Bay Estuary Program] (TBEP) was established in 1991. The governance arrangement for Tampa Bay is complex, and includes various programs implemented by multiple local, county, regional, state and federal organizations. The key partners include three counties, three cities, the [http://www.swfwmd.state.fl.us/| Southwest Florida Water Management District], the [http://www.dep.state.fl.us/| Florida Department of Environmental Protection], and the [http://www.epa.gov/| U.S. Environmental Protection Agency]. TBEP relies upon collaborative action through an integrating governance structure that develops management plans and implements them. TBEP spent its first six years conducting extensive public participation and scientific research to build consensus on program goals and the elements of a comprehensive management plan. <br />
<br />
TBEP’s first Comprehensive Conservation and Management Plan (CCMP), titled Charting the Course, was completed in 1996 and approved by the EPA that same year. The CCMP assigns the bay's most pressing problems to eight action plans—water and sediment quality, habitats, wildlife, dredging, oil spills, invasive species, public access and education. The action plans are designed to help contribute to 11 goals, several of which are quantifiable and measurable. The CCMP was updated in 2006 after an assessment and identification of emerging issues.<br />
<br />
==Program Administration==<br />
The TBEP has a small staff that serves as a coordinating body for the management committees and the activities of the partner institutions. The TBEP staff perform a variety of services including: convening groups to discuss bay issues; conducting research, advocating for the protection of the bay; organizing projects to address bay problems; providing mini-grants to community groups; providing technical assistance; coordinating outreach; and serving as a member of other collaborative organizations in the Bay <ref name="imp">Imperial, Mark T., The Tampa Bay Estuary Program: Developing and Implementing an Interlocal Agreement, A technical report prepared to support a final report to the National Academy of Public Administration as part of their Learning from Innovations in Environmental Protection Project (Washington, DC: National Academy of Public Administration, July 2000)</ref>. <br />
<br />
Two programs stand out as TBEP successes: 1) the Interlocal Agreement, and 2) Partnership to Reduce Nitrogen Loadings<br />
<br />
# '''Interlocal Agreement'''<br />
<br />
While the CCMP sets the goals and priorities, it is at its roots a voluntary plan without enforcement capabilities. Concerned that it would be seen as only yet another plan, leaders advocated for a more formal binding agreement between partners. After much negotiation, the partners signed an “Interlocal Agreement” in 1998, which committed local governments to attaining the CCMP’s goals. <br />
<br />
The Interlocal Agreement has served as a model for other programs striving to meet more stringent standards for water quality. Each partner submits action plans that document how they support the CCMP’s goals and objectives. The regulatory partners have agreed to streamline their regulatory programs. Fifteen partners, including the EPA, U.S. Army Corps of Engineers, a port authority and local governments have signed on to the Agreement. The Agreement has detailed rules governing its operations and decision-making procedures. It is important to note that there are no legal means to force partners to implement the Interlocal Agreement. Instead, it uses the power of peer accountability to keep partners engaged in the process <ref name="imp"/>. Long-term stakeholder relationships, based on previous projects and initiatives, have built a tradition of cooperation among scientists and managers. <br />
<br />
# '''Partnership to Reduce Nitrogen Loadings'''<br />
<br />
Advanced wastewater treatment for sewage plant discharges was mandated by law in 1972. With sewage treatment in place, it was clear that stormwater and nutrient loading were going to be the biggest issues in the Bay’s future. While the local governments agreed in the CCMP to reduce the portion of the loadings attributed to municipal storm water runoff and sewage treatment plants, the remaining reductions were to be addressed by a Nitrogen Management Consortium. Established in 1998, the Consortium is comprised of municipal governments and regulatory agencies, local companies, agricultural interests and electric utilities. The Consortium took on the task of creating the action plans necessary to meet the CCMP’s goals for reducing nitrogen from atmospheric deposition, industrial point sources, fertilizer shipping and handling practices, and intensive agriculture. The Consortium’s motto of “hold the line” on nutrient loadings from future growth was central to restoring seagrass habitat. <br />
<br />
Instead of allocating specific reductions to each source of nitrogen, the Consortium worked to identify individual or group projects that would achieve the reductions. This innovative approach helped identify the most cost-effective and environmentally beneficial projects.<br />
<br />
==Achievements==<br />
The progress made toward restoring the Tampa Bay habitats is impressive. TBEP has met or exceeded its goals for nitrogen reduction and habitat restoration. Collaborative mechanisms such as the Interlocal Agreement and the Nitrogen Management Consortium have been critical to establishing successful partnerships. <br />
<br />
From this foundation, TBEP has won stable funding, an effective land acquisition program, creation of effective science and citizen advisory committees, and the development of a collaborative monitoring program that has expanded to become the Florida West Coast Regional Ambient Monitoring Program (RAMP). In recognition of these efforts, EPA awarded the TBEP a bronze medal in 1998.<br />
<br />
In spite of these successes, a number of challenges remain. As development increases, there is a pressing need for improved linkages and collaboration with the land use planning regulators. <br />
<br />
<br />
<br />
==See also==<br />
<br />
===Internal Links===<br />
*[[Estuary]]<br />
*[[Estuaries and tidal rivers]]<br />
*[[Channel Islands National Marine Sanctuary – Case Study]]<br />
*[[US Coastal Zone Management Program]]<br />
*[[Coastal Barrier Resources System]]<br />
*[[Overview of Coastal Habitat Protection and Restoration in the United States]]<br />
*[[Essential Fish Habitat]]<br />
*[[Chesepeake Bay Program]] <br />
*[[Clean Water Act]]<br />
*[[US National Estuary Program]]<br />
*[[US National Estuarine Research Reserve System]]<br />
*[[US National Marine Sanctuaries]]<br />
*[[US National Wildlife Refuge System]]<br />
*[[Rhode Island Salt Pond Special Area Management Plan – Case Study]]<br />
*[[US Sea Grant College Program]]<br />
*[[US Army Corps of Engineers’ Coastal Programs]]<br />
<br />
===External Links===<br />
*Tampa Bay NEP http://www.tbep.org/ <br />
*Bay Soundings http://www.baysoundings.com/ <br />
*EPA National Estuary Program http://www.epa.gov/owow/estuaries/ <br />
*Association of NEPs http://www.nationalestuaries.org/ <br />
<br />
===Further Reading===<br />
*Building Consensual Institutions: Networks and the National Estuary Program Mark Schneider http://www.buzzardsbay.org/download/nep-networks-paper.pdf <br />
<br />
==References==<br />
<references/><br />
<br />
<br />
{{authors <br />
|AuthorID1=19106<br />
|AuthorName1= Olsen <br />
|AuthorFullName1= Stephen Bloye Olsen <br />
|AuthorID2=19107 <br />
|AuthorName2= Ricci <br />
|AuthorFullName2= Glenn Ricci}}<br />
<br />
[[Category:Articles by Glenn Ricci]]<br />
[[Category:Coastal management]]<br />
[[Category:Estuaries and tidal rivers]]<br />
[[Category:Location of coastal and marine areas]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Template:This_weeks_featured_article&diff=28627
Template:This weeks featured article
2009-03-27T11:00:58Z
<p>Wouter Kreiken: /* US Army Corps of Engineers’ Coastal Programs */</p>
<hr />
<div>==US Army Corps of Engineers’ Coastal Programs==<br />
<br />
[[Image:USACE.jpg|thumb|250px|right|Figure 1: The United States Army Corps of Engineers (USACE) serves the Armed Forces and the Nation by providing vital engineering services and capabilities.]]<br />
<br />
The US Army Corps of Engineers (USACE) <ref>USACE Website http://www.usace.army.mil/</ref> is a federal agency within the Department of Defense mandated to provide both military and civil works services. In coastal regions, its primary roles include protecting and [[Overview of Coastal Habitat Protection and Restoration in the United States|restoring habitat]], maintaining navigable waters, conducting [[beach nourishment]], undertaking [[Flood (overflow)| flood control]] projects and regulating coastal restoration projects. <br />
<br />
The USACE’s military service dates to 1775. Its first water works project began in 1812. After the passage of the Rivers & Harbors Act of 1899, the USACE regulated activities in navigable waterways. Passage of the [http://www.epa.gov/watertrain/cwa/| Clean Water Act] in 1972 vastly increased the USACE’s authority over dredging and filling in waters and wetlands. The Corps is the lead federal flood control agency and a major provider of hydroelectric energy. In the late 1960s, the Corps became a leading environmental preservation and restoration agency. It is a leading partner in one of the largest restoration projects ever attempted—restoration of the hydrologic regime in the Florida Everglades.</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Talk:TBT_and_Imposex&diff=28217
Talk:TBT and Imposex
2009-03-11T16:32:31Z
<p>Wouter Kreiken: New page: fixed your signature - Wouter</p>
<hr />
<div>fixed your signature - Wouter</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=TBT_and_Imposex&diff=28216
TBT and Imposex
2009-03-11T16:32:07Z
<p>Wouter Kreiken: /* References */</p>
<hr />
<div>{{Revision}}<br />
This article describes the use of Tributyltin (TBT) in aquatic antifouling paints, its behaviour in the marine environment and one of its powerful negative effects in non-target species - the phenomenon of imposex in marine [[Gastropod|gastropods]] - which have led to the partial ban of this coumpound.<br />
<br />
<br />
===Introduction===<br />
Tributyltin (TBT) is a biocide compound which integrates certain antifouling paints used on the hulls of vessels to prevent biological fouling - a phenomenon which has considerable economic costs and environmental risks. Although very efficient, TBT has been subject to restrictions due to its [[Ecotoxicity|toxic effects]] in non-target species, detected at the end of the 1970s. One of this harmful effects is imposex – the masculinisation of females of certain marine snails in response of the exposure to TBT concentration, in the magnitude of ng.l-1. So far this phenomenon has been described for over 150 species. The sensitiveness and high correlation between the intensity of this phenomenon and the environmental concentrations of TBT allow the use of certain [[Gastropod|gastropod]] species as indicators of the degree of contamination in coastal zones. Though the use of TBT has been forbidden in many countries for vessels smaller than 25 m, the contamination levels are still a concern, particularly close to areas of intense boating and associated activities, such as fishing and commercial ports, marinas and dry-docks.<br />
<br />
===Why the need of antifoulings?===<br />
<br />
====The Problem of Fouling in Vessels====<br />
Any submersed rigid structure can work as substrate and be colonized by several marine organisms. It is estimated that there are over 4000 marine fouling species. In the case of vessels, the degree of fouling of the hull depends on the time of submersion, the time the vessel is immobilized or its speed, but mainly on the features of the marine environment. Without an antifouling protection, the fouling can reach 150 kg per square meter, in less than 6 months. This phenomenon leads to an increase in the weight of the vessel and the drag resistance of the hull surface, which directly affect the speed, manoverability and the fuel consumption (increasing up to 40%), leading to more frequent maintenance operations, higher costs and higher emissions of polluting gases. Additionally, the hulls can work as vectors of translocation of organisms from one place to another, increasing the risks of introducing non-native, [[invasive species]].<br />
[[Image:Fouling_boat.jpg|thumb|250px|left|Fouling on the hull of a small boat]]<br />
<br />
====Antifouling methods and TBT====<br />
The problem of fouling in vessels was recognised since the beginning of navigation. The ancient Phoenicians and Carthaginians were thought to have used copper sheathing and the Greeks and Romans both used lead sheathing on their ships’ hulls. More recent methods included the usage of paints containing organic compounds of lead, arsenic, mercury and halogens (''e.g.'' DDT) and copper oxide. The later is still widely used. <br />
The first antifouling paints using organic compounds of tin started appearing in the second half of the 20th century and quickly dominated the markets during the following decades. Even today, TBT is globaly considered as the most effective solution developed so far to prevent fouling.<br />
<br />
====Sources and behaviour of TBT in aquatic systems====<br />
Antifouling systems represent the biggest and direct source of this pollutant. <br />
A TBT-based paint can be composed up to 3% of tin and a large commercial vessel can release more than 200g of TBT to the aquatic environment in only 3 days of permanence in a port.<br />
Aditionally, dry-docks and boatyards can also be relevant sources of antifouling paints (and other polutants), where old paint removal and repaint procedures take place. Most of the residues end up in the surrounding environment.<br />
<br />
When released into the water TBT can be degradated into less harmful forms by microrganisms and ultra-violet radiation. However, due to its high affinity to particles it will be easily transported to the sediments, where its concentration is typically higher than in the water. Here, organotin compounds are exceptionally stable and the concentration can remain high for a long time even after the sources have ceased.<br />
In the water, TBT can remain for a few days or months but in the sediments its half-life can extend for several months, years or even decades.<br />
<br />
[[Image:Boatyard antifouling.jpg|center|300px|Dry-docks and boatyards: Lack of proper containment during antifouling paint removal can result in deleterious substances being released into the aquatic environment.<br />
|frame]]<br />
<br />
===Effects in non-target species===<br />
<br />
====The case of the Bay of Arcachon (France)====<br />
During the period when TBT was being widely used as antifouling, the production of oisters in the Bay of Arcachon (France) almost collapsed. This coastal area is sumultaneasly a place of production of this shellfish and an area of intense recreative boating. Although the knowledge of TBT was very limited at the time, the French Authorities restricted the use of the compound in antifouling paints in the region, in a rare example of precautionary principle. Later on, it became clear that TBT was responsible for the failures in the reproduction and abnormal shell development of the oisters.<br />
<br />
[[Image:Dog_whelk_nucella_lapillus.jpg|thumb|250px|right|Dog whelk ''Nucella lapillus'']]<br />
<br />
====Imposex in marine snails====<br />
Also in the beginning of the 70’s certain reproductive abnormalities in other molluscs were discovered, which were later proved to result from exposure to TBT. In certain species of [[Gastropod|gastropods]] with separate genders, the females presented a penis and/or vas deferens. The term “imposex” was given as “a superimposition of male features in females” and was first described in dog whelk (''Nucella lapillus''). Soon it was clear that this was a generalised phenomenon – not only all the populations of dog whelk analysed in southwest England were affected but worldwide the same phenomenon was reported and for different species of snails, particularly in areas of intense maritime traffic. So far, imposex and intersex (a similiar phenomenon) have been described in over 150 species of marine snails. More developed stages of imposex can lead to the sterilization and premature death of the females, affecting the entire population. However, the most dramatic aspect of this [[Endocrine disrupting compounds in the coastal environment|endocrine disruptor]] is the fact that TBT can act at extremely low concentrations: a few nanograms per litre is enough to trigger imposex in marine snails - the equivalent of 1 g of salt dissolved in a square pool of 100 m side and 100m depth!<br />
<br />
====Effects in other species====<br />
The knowledge of TBT, its toxicity and risks to non-target organisms, including humans, is still limited. However, studies suggest several harmful effects on the imune and neurological systems and embrios in mammals and described toxicity to plankton, algaes, fish and marine birds. It is known that top predators from marine [[Ecosystem|ecosystems]] can [[Bio-accumulation|accumulate]] significant amounts of [[Pollutant|pollutents]]. TBT is not an exception and has been already detected in [[Cetacean|cetaceans]] and seals, sharks and tunas.<br />
<br />
[[Image:imposex satges.jpg|thumb|300px|left|Schematic representation of the stages of imposex development in netted dog whelk (''Nassarius reticulatus'') (Barroso, 2001)]]<br />
<br />
===Monitoring of TBT contamination===<br />
<br />
====Imposex as an indicator of TBT contamination====<br />
Some species of snails have been used as bio-indicators to evaluate and compare the degree of TBT contamination in aquatic environments. They are suitable species since:<br />
*the stage of imposex reflects the amount of TBT present in the tissues of the organism and in the surrounding environment <br />
*the imposex is triggered by extremelly low concentrations – close to the level of detection of measuring instruments<br />
*marine snails can be very commun in certain habitats and have restricted mobility<br />
<br />
<br />
===Restrictions to TBT===<br />
Since 1988 the International Maritime Organization ([http://www.imo.org/ IMO]), through the Marine Environment Protection Committee (MEPC), has recognised the harmful effects of the antifouling systems, particularly TBT. In 1990 the MEPC recommended the IMO Member States to restrict the usage of TBT in boats smaller than 25m (as the recreation boating was considered to be the main direct input) and to establish maximum release rates for the antifouling paints. As the evidences of the negative impacts and toxicity of TBT increased, IMO adopted the International Convention on the Control of Harmful Anti-fouling Systems on Ships with the intention to globally ban TBT, starting in 2008. The ratification of this proposal was slow and though the number of joining countries has increased, the goals haven't been met.<br />
France, in 1982, was the first country to forbid the use of TBT in boats smaller that 25m, followed by the UK in 1987. The rest of the EU gradually joined the action. Japan has banned the organic compounds of tin from antifouling paints in 1990 and has called for a global ban. Other countries such as Switzerland, Austria and New Zealand voluntarily followed the IMO recomendation. Most developed countries have adopted legislation restricting the use of TBT and alternative methods are being used and developed.<br />
<br />
==See also==<br />
<br />
===Internal Links===<br />
*[[Coastal pollution and impacts]]<br />
*[[Endocrine disrupting compounds in the coastal environment]]<br />
*[[Pollution laws and regulations]]<br />
*[[Pollution indicators]]<br />
*[[Differentiation of major algal groups by optical absorption signatures]]<br />
<br />
===External Links===<br />
*[http://www.imo.org| International Maritime Organization] <br />
<br />
==References==<br />
<references/><br />
<br />
<br />
{{author <br />
|AuthorID=19207<br />
|AuthorFullName= Veiga, Joana M<br />
|AuthorName=Veiga, Joana M}}<br />
<br />
<br />
[[Category:Coastal and marine pollution]]<br />
[[Category:Maritime transportation]]<br />
[[Category:Theme 9]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=TBT_and_Imposex&diff=28215
TBT and Imposex
2009-03-11T16:30:56Z
<p>Wouter Kreiken: /* References */</p>
<hr />
<div>{{Revision}}<br />
This article describes the use of Tributyltin (TBT) in aquatic antifouling paints, its behaviour in the marine environment and one of its powerful negative effects in non-target species - the phenomenon of imposex in marine [[Gastropod|gastropods]] - which have led to the partial ban of this coumpound.<br />
<br />
<br />
===Introduction===<br />
Tributyltin (TBT) is a biocide compound which integrates certain antifouling paints used on the hulls of vessels to prevent biological fouling - a phenomenon which has considerable economic costs and environmental risks. Although very efficient, TBT has been subject to restrictions due to its [[Ecotoxicity|toxic effects]] in non-target species, detected at the end of the 1970s. One of this harmful effects is imposex – the masculinisation of females of certain marine snails in response of the exposure to TBT concentration, in the magnitude of ng.l-1. So far this phenomenon has been described for over 150 species. The sensitiveness and high correlation between the intensity of this phenomenon and the environmental concentrations of TBT allow the use of certain [[Gastropod|gastropod]] species as indicators of the degree of contamination in coastal zones. Though the use of TBT has been forbidden in many countries for vessels smaller than 25 m, the contamination levels are still a concern, particularly close to areas of intense boating and associated activities, such as fishing and commercial ports, marinas and dry-docks.<br />
<br />
===Why the need of antifoulings?===<br />
<br />
====The Problem of Fouling in Vessels====<br />
Any submersed rigid structure can work as substrate and be colonized by several marine organisms. It is estimated that there are over 4000 marine fouling species. In the case of vessels, the degree of fouling of the hull depends on the time of submersion, the time the vessel is immobilized or its speed, but mainly on the features of the marine environment. Without an antifouling protection, the fouling can reach 150 kg per square meter, in less than 6 months. This phenomenon leads to an increase in the weight of the vessel and the drag resistance of the hull surface, which directly affect the speed, manoverability and the fuel consumption (increasing up to 40%), leading to more frequent maintenance operations, higher costs and higher emissions of polluting gases. Additionally, the hulls can work as vectors of translocation of organisms from one place to another, increasing the risks of introducing non-native, [[invasive species]].<br />
[[Image:Fouling_boat.jpg|thumb|250px|left|Fouling on the hull of a small boat]]<br />
<br />
====Antifouling methods and TBT====<br />
The problem of fouling in vessels was recognised since the beginning of navigation. The ancient Phoenicians and Carthaginians were thought to have used copper sheathing and the Greeks and Romans both used lead sheathing on their ships’ hulls. More recent methods included the usage of paints containing organic compounds of lead, arsenic, mercury and halogens (''e.g.'' DDT) and copper oxide. The later is still widely used. <br />
The first antifouling paints using organic compounds of tin started appearing in the second half of the 20th century and quickly dominated the markets during the following decades. Even today, TBT is globaly considered as the most effective solution developed so far to prevent fouling.<br />
<br />
====Sources and behaviour of TBT in aquatic systems====<br />
Antifouling systems represent the biggest and direct source of this pollutant. <br />
A TBT-based paint can be composed up to 3% of tin and a large commercial vessel can release more than 200g of TBT to the aquatic environment in only 3 days of permanence in a port.<br />
Aditionally, dry-docks and boatyards can also be relevant sources of antifouling paints (and other polutants), where old paint removal and repaint procedures take place. Most of the residues end up in the surrounding environment.<br />
<br />
When released into the water TBT can be degradated into less harmful forms by microrganisms and ultra-violet radiation. However, due to its high affinity to particles it will be easily transported to the sediments, where its concentration is typically higher than in the water. Here, organotin compounds are exceptionally stable and the concentration can remain high for a long time even after the sources have ceased.<br />
In the water, TBT can remain for a few days or months but in the sediments its half-life can extend for several months, years or even decades.<br />
<br />
[[Image:Boatyard antifouling.jpg|center|300px|Dry-docks and boatyards: Lack of proper containment during antifouling paint removal can result in deleterious substances being released into the aquatic environment.<br />
|frame]]<br />
<br />
===Effects in non-target species===<br />
<br />
====The case of the Bay of Arcachon (France)====<br />
During the period when TBT was being widely used as antifouling, the production of oisters in the Bay of Arcachon (France) almost collapsed. This coastal area is sumultaneasly a place of production of this shellfish and an area of intense recreative boating. Although the knowledge of TBT was very limited at the time, the French Authorities restricted the use of the compound in antifouling paints in the region, in a rare example of precautionary principle. Later on, it became clear that TBT was responsible for the failures in the reproduction and abnormal shell development of the oisters.<br />
<br />
[[Image:Dog_whelk_nucella_lapillus.jpg|thumb|250px|right|Dog whelk ''Nucella lapillus'']]<br />
<br />
====Imposex in marine snails====<br />
Also in the beginning of the 70’s certain reproductive abnormalities in other molluscs were discovered, which were later proved to result from exposure to TBT. In certain species of [[Gastropod|gastropods]] with separate genders, the females presented a penis and/or vas deferens. The term “imposex” was given as “a superimposition of male features in females” and was first described in dog whelk (''Nucella lapillus''). Soon it was clear that this was a generalised phenomenon – not only all the populations of dog whelk analysed in southwest England were affected but worldwide the same phenomenon was reported and for different species of snails, particularly in areas of intense maritime traffic. So far, imposex and intersex (a similiar phenomenon) have been described in over 150 species of marine snails. More developed stages of imposex can lead to the sterilization and premature death of the females, affecting the entire population. However, the most dramatic aspect of this [[Endocrine disrupting compounds in the coastal environment|endocrine disruptor]] is the fact that TBT can act at extremely low concentrations: a few nanograms per litre is enough to trigger imposex in marine snails - the equivalent of 1 g of salt dissolved in a square pool of 100 m side and 100m depth!<br />
<br />
====Effects in other species====<br />
The knowledge of TBT, its toxicity and risks to non-target organisms, including humans, is still limited. However, studies suggest several harmful effects on the imune and neurological systems and embrios in mammals and described toxicity to plankton, algaes, fish and marine birds. It is known that top predators from marine [[Ecosystem|ecosystems]] can [[Bio-accumulation|accumulate]] significant amounts of [[Pollutant|pollutents]]. TBT is not an exception and has been already detected in [[Cetacean|cetaceans]] and seals, sharks and tunas.<br />
<br />
[[Image:imposex satges.jpg|thumb|300px|left|Schematic representation of the stages of imposex development in netted dog whelk (''Nassarius reticulatus'') (Barroso, 2001)]]<br />
<br />
===Monitoring of TBT contamination===<br />
<br />
====Imposex as an indicator of TBT contamination====<br />
Some species of snails have been used as bio-indicators to evaluate and compare the degree of TBT contamination in aquatic environments. They are suitable species since:<br />
*the stage of imposex reflects the amount of TBT present in the tissues of the organism and in the surrounding environment <br />
*the imposex is triggered by extremelly low concentrations – close to the level of detection of measuring instruments<br />
*marine snails can be very commun in certain habitats and have restricted mobility<br />
<br />
<br />
===Restrictions to TBT===<br />
Since 1988 the International Maritime Organization ([http://www.imo.org/ IMO]), through the Marine Environment Protection Committee (MEPC), has recognised the harmful effects of the antifouling systems, particularly TBT. In 1990 the MEPC recommended the IMO Member States to restrict the usage of TBT in boats smaller than 25m (as the recreation boating was considered to be the main direct input) and to establish maximum release rates for the antifouling paints. As the evidences of the negative impacts and toxicity of TBT increased, IMO adopted the International Convention on the Control of Harmful Anti-fouling Systems on Ships with the intention to globally ban TBT, starting in 2008. The ratification of this proposal was slow and though the number of joining countries has increased, the goals haven't been met.<br />
France, in 1982, was the first country to forbid the use of TBT in boats smaller that 25m, followed by the UK in 1987. The rest of the EU gradually joined the action. Japan has banned the organic compounds of tin from antifouling paints in 1990 and has called for a global ban. Other countries such as Switzerland, Austria and New Zealand voluntarily followed the IMO recomendation. Most developed countries have adopted legislation restricting the use of TBT and alternative methods are being used and developed.<br />
<br />
==See also==<br />
<br />
===Internal Links===<br />
*[[Coastal pollution and impacts]]<br />
*[[Endocrine disrupting compounds in the coastal environment]]<br />
*[[Pollution laws and regulations]]<br />
*[[Pollution indicators]]<br />
*[[Differentiation of major algal groups by optical absorption signatures]]<br />
<br />
===External Links===<br />
*[http://www.imo.org| International Maritime Organization] <br />
<br />
==References==<br />
<references/><br />
<br />
<br />
{{author <br />
|AuthorFullName= Veiga, Joana M<br />
|AuthorName=Veiga, Joana M}}<br />
<br />
<br />
[[Category:Coastal and marine pollution]]<br />
[[Category:Maritime transportation]]<br />
[[Category:Theme 9]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=TBT_and_Imposex&diff=28214
TBT and Imposex
2009-03-11T16:19:41Z
<p>Wouter Kreiken: /* Antifouling methods and TBT */</p>
<hr />
<div>{{Revision}}<br />
This article describes the use of Tributyltin (TBT) in aquatic antifouling paints, its behaviour in the marine environment and one of its powerful negative effects in non-target species - the phenomenon of imposex in marine [[Gastropod|gastropods]] - which have led to the partial ban of this coumpound.<br />
<br />
<br />
===Introduction===<br />
Tributyltin (TBT) is a biocide compound which integrates certain antifouling paints used on the hulls of vessels to prevent biological fouling - a phenomenon which has considerable economic costs and environmental risks. Although very efficient, TBT has been subject to restrictions due to its [[Ecotoxicity|toxic effects]] in non-target species, detected at the end of the 1970s. One of this harmful effects is imposex – the masculinisation of females of certain marine snails in response of the exposure to TBT concentration, in the magnitude of ng.l-1. So far this phenomenon has been described for over 150 species. The sensitiveness and high correlation between the intensity of this phenomenon and the environmental concentrations of TBT allow the use of certain [[Gastropod|gastropod]] species as indicators of the degree of contamination in coastal zones. Though the use of TBT has been forbidden in many countries for vessels smaller than 25 m, the contamination levels are still a concern, particularly close to areas of intense boating and associated activities, such as fishing and commercial ports, marinas and dry-docks.<br />
<br />
===Why the need of antifoulings?===<br />
<br />
====The Problem of Fouling in Vessels====<br />
Any submersed rigid structure can work as substrate and be colonized by several marine organisms. It is estimated that there are over 4000 marine fouling species. In the case of vessels, the degree of fouling of the hull depends on the time of submersion, the time the vessel is immobilized or its speed, but mainly on the features of the marine environment. Without an antifouling protection, the fouling can reach 150 kg per square meter, in less than 6 months. This phenomenon leads to an increase in the weight of the vessel and the drag resistance of the hull surface, which directly affect the speed, manoverability and the fuel consumption (increasing up to 40%), leading to more frequent maintenance operations, higher costs and higher emissions of polluting gases. Additionally, the hulls can work as vectors of translocation of organisms from one place to another, increasing the risks of introducing non-native, [[invasive species]].<br />
[[Image:Fouling_boat.jpg|thumb|250px|left|Fouling on the hull of a small boat]]<br />
<br />
====Antifouling methods and TBT====<br />
The problem of fouling in vessels was recognised since the beginning of navigation. The ancient Phoenicians and Carthaginians were thought to have used copper sheathing and the Greeks and Romans both used lead sheathing on their ships’ hulls. More recent methods included the usage of paints containing organic compounds of lead, arsenic, mercury and halogens (''e.g.'' DDT) and copper oxide. The later is still widely used. <br />
The first antifouling paints using organic compounds of tin started appearing in the second half of the 20th century and quickly dominated the markets during the following decades. Even today, TBT is globaly considered as the most effective solution developed so far to prevent fouling.<br />
<br />
====Sources and behaviour of TBT in aquatic systems====<br />
Antifouling systems represent the biggest and direct source of this pollutant. <br />
A TBT-based paint can be composed up to 3% of tin and a large commercial vessel can release more than 200g of TBT to the aquatic environment in only 3 days of permanence in a port.<br />
Aditionally, dry-docks and boatyards can also be relevant sources of antifouling paints (and other polutants), where old paint removal and repaint procedures take place. Most of the residues end up in the surrounding environment.<br />
<br />
When released into the water TBT can be degradated into less harmful forms by microrganisms and ultra-violet radiation. However, due to its high affinity to particles it will be easily transported to the sediments, where its concentration is typically higher than in the water. Here, organotin compounds are exceptionally stable and the concentration can remain high for a long time even after the sources have ceased.<br />
In the water, TBT can remain for a few days or months but in the sediments its half-life can extend for several months, years or even decades.<br />
<br />
[[Image:Boatyard antifouling.jpg|center|300px|Dry-docks and boatyards: Lack of proper containment during antifouling paint removal can result in deleterious substances being released into the aquatic environment.<br />
|frame]]<br />
<br />
===Effects in non-target species===<br />
<br />
====The case of the Bay of Arcachon (France)====<br />
During the period when TBT was being widely used as antifouling, the production of oisters in the Bay of Arcachon (France) almost collapsed. This coastal area is sumultaneasly a place of production of this shellfish and an area of intense recreative boating. Although the knowledge of TBT was very limited at the time, the French Authorities restricted the use of the compound in antifouling paints in the region, in a rare example of precautionary principle. Later on, it became clear that TBT was responsible for the failures in the reproduction and abnormal shell development of the oisters.<br />
<br />
[[Image:Dog_whelk_nucella_lapillus.jpg|thumb|250px|right|Dog whelk ''Nucella lapillus'']]<br />
<br />
====Imposex in marine snails====<br />
Also in the beginning of the 70’s certain reproductive abnormalities in other molluscs were discovered, which were later proved to result from exposure to TBT. In certain species of [[Gastropod|gastropods]] with separate genders, the females presented a penis and/or vas deferens. The term “imposex” was given as “a superimposition of male features in females” and was first described in dog whelk (''Nucella lapillus''). Soon it was clear that this was a generalised phenomenon – not only all the populations of dog whelk analysed in southwest England were affected but worldwide the same phenomenon was reported and for different species of snails, particularly in areas of intense maritime traffic. So far, imposex and intersex (a similiar phenomenon) have been described in over 150 species of marine snails. More developed stages of imposex can lead to the sterilization and premature death of the females, affecting the entire population. However, the most dramatic aspect of this [[Endocrine disrupting compounds in the coastal environment|endocrine disruptor]] is the fact that TBT can act at extremely low concentrations: a few nanograms per litre is enough to trigger imposex in marine snails - the equivalent of 1 g of salt dissolved in a square pool of 100 m side and 100m depth!<br />
<br />
====Effects in other species====<br />
The knowledge of TBT, its toxicity and risks to non-target organisms, including humans, is still limited. However, studies suggest several harmful effects on the imune and neurological systems and embrios in mammals and described toxicity to plankton, algaes, fish and marine birds. It is known that top predators from marine [[Ecosystem|ecosystems]] can [[Bio-accumulation|accumulate]] significant amounts of [[Pollutant|pollutents]]. TBT is not an exception and has been already detected in [[Cetacean|cetaceans]] and seals, sharks and tunas.<br />
<br />
[[Image:imposex satges.jpg|thumb|300px|left|Schematic representation of the stages of imposex development in netted dog whelk (''Nassarius reticulatus'') (Barroso, 2001)]]<br />
<br />
===Monitoring of TBT contamination===<br />
<br />
====Imposex as an indicator of TBT contamination====<br />
Some species of snails have been used as bio-indicators to evaluate and compare the degree of TBT contamination in aquatic environments. They are suitable species since:<br />
*the stage of imposex reflects the amount of TBT present in the tissues of the organism and in the surrounding environment <br />
*the imposex is triggered by extremelly low concentrations – close to the level of detection of measuring instruments<br />
*marine snails can be very commun in certain habitats and have restricted mobility<br />
<br />
<br />
===Restrictions to TBT===<br />
Since 1988 the International Maritime Organization ([http://www.imo.org/ IMO]), through the Marine Environment Protection Committee (MEPC), has recognised the harmful effects of the antifouling systems, particularly TBT. In 1990 the MEPC recommended the IMO Member States to restrict the usage of TBT in boats smaller than 25m (as the recreation boating was considered to be the main direct input) and to establish maximum release rates for the antifouling paints. As the evidences of the negative impacts and toxicity of TBT increased, IMO adopted the International Convention on the Control of Harmful Anti-fouling Systems on Ships with the intention to globally ban TBT, starting in 2008. The ratification of this proposal was slow and though the number of joining countries has increased, the goals haven't been met.<br />
France, in 1982, was the first country to forbid the use of TBT in boats smaller that 25m, followed by the UK in 1987. The rest of the EU gradually joined the action. Japan has banned the organic compounds of tin from antifouling paints in 1990 and has called for a global ban. Other countries such as Switzerland, Austria and New Zealand voluntarily followed the IMO recomendation. Most developed countries have adopted legislation restricting the use of TBT and alternative methods are being used and developed.<br />
<br />
==See also==<br />
<br />
===Internal Links===<br />
*[[Coastal pollution and impacts]]<br />
*[[Endocrine disrupting compounds in the coastal environment]]<br />
*[[Pollution laws and regulations]]<br />
*[[Pollution indicators]]<br />
*[[Differentiation of major algal groups by optical absorption signatures]]<br />
<br />
===External Links===<br />
*[http://www.imo.org| International Maritime Organization] <br />
<br />
==References==<br />
<references/><br />
<br />
<br />
{{author <br />
|AuthorFullName= Veiga, Joana M<br />
|AuthorName=Username}}<br />
<br />
<br />
[[Category:Coastal and marine pollution]]<br />
[[Category:Maritime transportation]]<br />
[[Category:Theme 9]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=TBT_and_Imposex&diff=28213
TBT and Imposex
2009-03-11T16:17:17Z
<p>Wouter Kreiken: /* Imposex in marine snails */</p>
<hr />
<div>{{Revision}}<br />
This article describes the use of Tributyltin (TBT) in aquatic antifouling paints, its behaviour in the marine environment and one of its powerful negative effects in non-target species - the phenomenon of imposex in marine [[Gastropod|gastropods]] - which have led to the partial ban of this coumpound.<br />
<br />
<br />
===Introduction===<br />
Tributyltin (TBT) is a biocide compound which integrates certain antifouling paints used on the hulls of vessels to prevent biological fouling - a phenomenon which has considerable economic costs and environmental risks. Although very efficient, TBT has been subject to restrictions due to its [[Ecotoxicity|toxic effects]] in non-target species, detected at the end of the 1970s. One of this harmful effects is imposex – the masculinisation of females of certain marine snails in response of the exposure to TBT concentration, in the magnitude of ng.l-1. So far this phenomenon has been described for over 150 species. The sensitiveness and high correlation between the intensity of this phenomenon and the environmental concentrations of TBT allow the use of certain [[Gastropod|gastropod]] species as indicators of the degree of contamination in coastal zones. Though the use of TBT has been forbidden in many countries for vessels smaller than 25 m, the contamination levels are still a concern, particularly close to areas of intense boating and associated activities, such as fishing and commercial ports, marinas and dry-docks.<br />
<br />
===Why the need of antifoulings?===<br />
<br />
====The Problem of Fouling in Vessels====<br />
Any submersed rigid structure can work as substrate and be colonized by several marine organisms. It is estimated that there are over 4000 marine fouling species. In the case of vessels, the degree of fouling of the hull depends on the time of submersion, the time the vessel is immobilized or its speed, but mainly on the features of the marine environment. Without an antifouling protection, the fouling can reach 150 kg per square meter, in less than 6 months. This phenomenon leads to an increase in the weight of the vessel and the drag resistance of the hull surface, which directly affect the speed, manoverability and the fuel consumption (increasing up to 40%), leading to more frequent maintenance operations, higher costs and higher emissions of polluting gases. Additionally, the hulls can work as vectors of translocation of organisms from one place to another, increasing the risks of introducing non-native, [[invasive species]].<br />
[[Image:Fouling_boat.jpg|thumb|250px|left|Fouling on the hull of a small boat]]<br />
<br />
====Antifouling methods and TBT====<br />
The problem of fouling in vessels was recognised since the beginning of navigation. The ancient Phoenicians and Carthaginians were thought to have used copper sheathing and the Greeks and Romans both used lead sheathing on their ships’ hulls. More recent methods included the usage of paints containing organic compounds of lead, arsenic, mercury and halogens (''e.g.'' DDT) and copper oxide. The later is still widely used. <br />
The first antifouling paints using organic compounds of tin started appearing in the second half of the XX century and quickly dominated the markets during the following decades. Even today, TBT is globaly considered as the most effective solution developed so far to prevent fouling.<br />
<br />
====Sources and behaviour of TBT in aquatic systems====<br />
Antifouling systems represent the biggest and direct source of this pollutant. <br />
A TBT-based paint can be composed up to 3% of tin and a large commercial vessel can release more than 200g of TBT to the aquatic environment in only 3 days of permanence in a port.<br />
Aditionally, dry-docks and boatyards can also be relevant sources of antifouling paints (and other polutants), where old paint removal and repaint procedures take place. Most of the residues end up in the surrounding environment.<br />
<br />
When released into the water TBT can be degradated into less harmful forms by microrganisms and ultra-violet radiation. However, due to its high affinity to particles it will be easily transported to the sediments, where its concentration is typically higher than in the water. Here, organotin compounds are exceptionally stable and the concentration can remain high for a long time even after the sources have ceased.<br />
In the water, TBT can remain for a few days or months but in the sediments its half-life can extend for several months, years or even decades.<br />
<br />
[[Image:Boatyard antifouling.jpg|center|300px|Dry-docks and boatyards: Lack of proper containment during antifouling paint removal can result in deleterious substances being released into the aquatic environment.<br />
|frame]]<br />
<br />
===Effects in non-target species===<br />
<br />
====The case of the Bay of Arcachon (France)====<br />
During the period when TBT was being widely used as antifouling, the production of oisters in the Bay of Arcachon (France) almost collapsed. This coastal area is sumultaneasly a place of production of this shellfish and an area of intense recreative boating. Although the knowledge of TBT was very limited at the time, the French Authorities restricted the use of the compound in antifouling paints in the region, in a rare example of precautionary principle. Later on, it became clear that TBT was responsible for the failures in the reproduction and abnormal shell development of the oisters.<br />
<br />
[[Image:Dog_whelk_nucella_lapillus.jpg|thumb|250px|right|Dog whelk ''Nucella lapillus'']]<br />
<br />
====Imposex in marine snails====<br />
Also in the beginning of the 70’s certain reproductive abnormalities in other molluscs were discovered, which were later proved to result from exposure to TBT. In certain species of [[Gastropod|gastropods]] with separate genders, the females presented a penis and/or vas deferens. The term “imposex” was given as “a superimposition of male features in females” and was first described in dog whelk (''Nucella lapillus''). Soon it was clear that this was a generalised phenomenon – not only all the populations of dog whelk analysed in southwest England were affected but worldwide the same phenomenon was reported and for different species of snails, particularly in areas of intense maritime traffic. So far, imposex and intersex (a similiar phenomenon) have been described in over 150 species of marine snails. More developed stages of imposex can lead to the sterilization and premature death of the females, affecting the entire population. However, the most dramatic aspect of this [[Endocrine disrupting compounds in the coastal environment|endocrine disruptor]] is the fact that TBT can act at extremely low concentrations: a few nanograms per litre is enough to trigger imposex in marine snails - the equivalent of 1 g of salt dissolved in a square pool of 100 m side and 100m depth!<br />
<br />
====Effects in other species====<br />
The knowledge of TBT, its toxicity and risks to non-target organisms, including humans, is still limited. However, studies suggest several harmful effects on the imune and neurological systems and embrios in mammals and described toxicity to plankton, algaes, fish and marine birds. It is known that top predators from marine [[Ecosystem|ecosystems]] can [[Bio-accumulation|accumulate]] significant amounts of [[Pollutant|pollutents]]. TBT is not an exception and has been already detected in [[Cetacean|cetaceans]] and seals, sharks and tunas.<br />
<br />
[[Image:imposex satges.jpg|thumb|300px|left|Schematic representation of the stages of imposex development in netted dog whelk (''Nassarius reticulatus'') (Barroso, 2001)]]<br />
<br />
===Monitoring of TBT contamination===<br />
<br />
====Imposex as an indicator of TBT contamination====<br />
Some species of snails have been used as bio-indicators to evaluate and compare the degree of TBT contamination in aquatic environments. They are suitable species since:<br />
*the stage of imposex reflects the amount of TBT present in the tissues of the organism and in the surrounding environment <br />
*the imposex is triggered by extremelly low concentrations – close to the level of detection of measuring instruments<br />
*marine snails can be very commun in certain habitats and have restricted mobility<br />
<br />
<br />
===Restrictions to TBT===<br />
Since 1988 the International Maritime Organization ([http://www.imo.org/ IMO]), through the Marine Environment Protection Committee (MEPC), has recognised the harmful effects of the antifouling systems, particularly TBT. In 1990 the MEPC recommended the IMO Member States to restrict the usage of TBT in boats smaller than 25m (as the recreation boating was considered to be the main direct input) and to establish maximum release rates for the antifouling paints. As the evidences of the negative impacts and toxicity of TBT increased, IMO adopted the International Convention on the Control of Harmful Anti-fouling Systems on Ships with the intention to globally ban TBT, starting in 2008. The ratification of this proposal was slow and though the number of joining countries has increased, the goals haven't been met.<br />
France, in 1982, was the first country to forbid the use of TBT in boats smaller that 25m, followed by the UK in 1987. The rest of the EU gradually joined the action. Japan has banned the organic compounds of tin from antifouling paints in 1990 and has called for a global ban. Other countries such as Switzerland, Austria and New Zealand voluntarily followed the IMO recomendation. Most developed countries have adopted legislation restricting the use of TBT and alternative methods are being used and developed.<br />
<br />
==See also==<br />
<br />
===Internal Links===<br />
*[[Coastal pollution and impacts]]<br />
*[[Endocrine disrupting compounds in the coastal environment]]<br />
*[[Pollution laws and regulations]]<br />
*[[Pollution indicators]]<br />
*[[Differentiation of major algal groups by optical absorption signatures]]<br />
<br />
===External Links===<br />
*[http://www.imo.org| International Maritime Organization] <br />
<br />
==References==<br />
<references/><br />
<br />
<br />
{{author <br />
|AuthorFullName= Veiga, Joana M<br />
|AuthorName=Username}}<br />
<br />
<br />
[[Category:Coastal and marine pollution]]<br />
[[Category:Maritime transportation]]<br />
[[Category:Theme 9]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=TBT_and_Imposex&diff=28212
TBT and Imposex
2009-03-11T16:11:53Z
<p>Wouter Kreiken: /* References */</p>
<hr />
<div>{{Revision}}<br />
This article describes the use of Tributyltin (TBT) in aquatic antifouling paints, its behaviour in the marine environment and one of its powerful negative effects in non-target species - the phenomenon of imposex in marine [[Gastropod|gastropods]] - which have led to the partial ban of this coumpound.<br />
<br />
<br />
===Introduction===<br />
Tributyltin (TBT) is a biocide compound which integrates certain antifouling paints used on the hulls of vessels to prevent biological fouling - a phenomenon which has considerable economic costs and environmental risks. Although very efficient, TBT has been subject to restrictions due to its [[Ecotoxicity|toxic effects]] in non-target species, detected at the end of the 1970s. One of this harmful effects is imposex – the masculinisation of females of certain marine snails in response of the exposure to TBT concentration, in the magnitude of ng.l-1. So far this phenomenon has been described for over 150 species. The sensitiveness and high correlation between the intensity of this phenomenon and the environmental concentrations of TBT allow the use of certain [[Gastropod|gastropod]] species as indicators of the degree of contamination in coastal zones. Though the use of TBT has been forbidden in many countries for vessels smaller than 25 m, the contamination levels are still a concern, particularly close to areas of intense boating and associated activities, such as fishing and commercial ports, marinas and dry-docks.<br />
<br />
===Why the need of antifoulings?===<br />
<br />
====The Problem of Fouling in Vessels====<br />
Any submersed rigid structure can work as substrate and be colonized by several marine organisms. It is estimated that there are over 4000 marine fouling species. In the case of vessels, the degree of fouling of the hull depends on the time of submersion, the time the vessel is immobilized or its speed, but mainly on the features of the marine environment. Without an antifouling protection, the fouling can reach 150 kg per square meter, in less than 6 months. This phenomenon leads to an increase in the weight of the vessel and the drag resistance of the hull surface, which directly affect the speed, manoverability and the fuel consumption (increasing up to 40%), leading to more frequent maintenance operations, higher costs and higher emissions of polluting gases. Additionally, the hulls can work as vectors of translocation of organisms from one place to another, increasing the risks of introducing non-native, [[invasive species]].<br />
[[Image:Fouling_boat.jpg|thumb|250px|left|Fouling on the hull of a small boat]]<br />
<br />
====Antifouling methods and TBT====<br />
The problem of fouling in vessels was recognised since the beginning of navigation. The ancient Phoenicians and Carthaginians were thought to have used copper sheathing and the Greeks and Romans both used lead sheathing on their ships’ hulls. More recent methods included the usage of paints containing organic compounds of lead, arsenic, mercury and halogens (''e.g.'' DDT) and copper oxide. The later is still widely used. <br />
The first antifouling paints using organic compounds of tin started appearing in the second half of the XX century and quickly dominated the markets during the following decades. Even today, TBT is globaly considered as the most effective solution developed so far to prevent fouling.<br />
<br />
====Sources and behaviour of TBT in aquatic systems====<br />
Antifouling systems represent the biggest and direct source of this pollutant. <br />
A TBT-based paint can be composed up to 3% of tin and a large commercial vessel can release more than 200g of TBT to the aquatic environment in only 3 days of permanence in a port.<br />
Aditionally, dry-docks and boatyards can also be relevant sources of antifouling paints (and other polutants), where old paint removal and repaint procedures take place. Most of the residues end up in the surrounding environment.<br />
<br />
When released into the water TBT can be degradated into less harmful forms by microrganisms and ultra-violet radiation. However, due to its high affinity to particles it will be easily transported to the sediments, where its concentration is typically higher than in the water. Here, organotin compounds are exceptionally stable and the concentration can remain high for a long time even after the sources have ceased.<br />
In the water, TBT can remain for a few days or months but in the sediments its half-life can extend for several months, years or even decades.<br />
<br />
[[Image:Boatyard antifouling.jpg|center|300px|Dry-docks and boatyards: Lack of proper containment during antifouling paint removal can result in deleterious substances being released into the aquatic environment.<br />
|frame]]<br />
<br />
===Effects in non-target species===<br />
<br />
====The case of the Bay of Arcachon (France)====<br />
During the period when TBT was being widely used as antifouling, the production of oisters in the Bay of Arcachon (France) almost collapsed. This coastal area is sumultaneasly a place of production of this shellfish and an area of intense recreative boating. Although the knowledge of TBT was very limited at the time, the French Authorities restricted the use of the compound in antifouling paints in the region, in a rare example of precautionary principle. Later on, it became clear that TBT was responsible for the failures in the reproduction and abnormal shell development of the oisters.<br />
<br />
[[Image:Dog_whelk_nucella_lapillus.jpg|thumb|250px|right|Dog whelk ''Nucella lapillus'']]<br />
<br />
====Imposex in marine snails====<br />
Also in the beginning of the 70’s certain reproductive abnormalities in other molluscs were discovered, which were later proved to result from exposure to TBT. In certain species of [[Gastropoda|gastropods]] with separate genders, the females presented a penis and/or vas deferens. The term “imposex” was given as “a superimposition of male features in females” and was first described in dog whelk (''Nucella lapillus''). Soon it was clear that this was a generalised phenomenon – not only all the populations of dog whelk analysed in southwest England were affected but worldwide the same phenomenon was reported and for different species of snails, particularly in areas of intense maritime traffic. So far, imposex and intersex (a similiar phenomenon) have been described in over 150 species of marine snails. More developed stages of imposex can lead to the sterilization and premature death of the females, affecting the entire population. However, the most dramatic aspect of this [[Endocrine disrupting compounds in the coastal environment|endocrine disruptor]] is the fact that TBT can act at extremely low concentrations: a few nanograms per litre is enough to trigger imposex in marine snails - the equivalent of 1 g of salt dissolved in a square pool of 100 m side and 100m depth!<br />
<br />
====Effects in other species====<br />
The knowledge of TBT, its toxicity and risks to non-target organisms, including humans, is still limited. However, studies suggest several harmful effects on the imune and neurological systems and embrios in mammals and described toxicity to plankton, algaes, fish and marine birds. It is known that top predators from marine [[Ecosystem|ecosystems]] can [[Bio-accumulation|accumulate]] significant amounts of [[Pollutant|pollutents]]. TBT is not an exception and has been already detected in [[Cetacean|cetaceans]] and seals, sharks and tunas.<br />
<br />
[[Image:imposex satges.jpg|thumb|300px|left|Schematic representation of the stages of imposex development in netted dog whelk (''Nassarius reticulatus'') (Barroso, 2001)]]<br />
<br />
===Monitoring of TBT contamination===<br />
<br />
====Imposex as an indicator of TBT contamination====<br />
Some species of snails have been used as bio-indicators to evaluate and compare the degree of TBT contamination in aquatic environments. They are suitable species since:<br />
*the stage of imposex reflects the amount of TBT present in the tissues of the organism and in the surrounding environment <br />
*the imposex is triggered by extremelly low concentrations – close to the level of detection of measuring instruments<br />
*marine snails can be very commun in certain habitats and have restricted mobility<br />
<br />
<br />
===Restrictions to TBT===<br />
Since 1988 the International Maritime Organization ([http://www.imo.org/ IMO]), through the Marine Environment Protection Committee (MEPC), has recognised the harmful effects of the antifouling systems, particularly TBT. In 1990 the MEPC recommended the IMO Member States to restrict the usage of TBT in boats smaller than 25m (as the recreation boating was considered to be the main direct input) and to establish maximum release rates for the antifouling paints. As the evidences of the negative impacts and toxicity of TBT increased, IMO adopted the International Convention on the Control of Harmful Anti-fouling Systems on Ships with the intention to globally ban TBT, starting in 2008. The ratification of this proposal was slow and though the number of joining countries has increased, the goals haven't been met.<br />
France, in 1982, was the first country to forbid the use of TBT in boats smaller that 25m, followed by the UK in 1987. The rest of the EU gradually joined the action. Japan has banned the organic compounds of tin from antifouling paints in 1990 and has called for a global ban. Other countries such as Switzerland, Austria and New Zealand voluntarily followed the IMO recomendation. Most developed countries have adopted legislation restricting the use of TBT and alternative methods are being used and developed.<br />
<br />
==See also==<br />
<br />
===Internal Links===<br />
*[[Coastal pollution and impacts]]<br />
*[[Endocrine disrupting compounds in the coastal environment]]<br />
*[[Pollution laws and regulations]]<br />
*[[Pollution indicators]]<br />
*[[Differentiation of major algal groups by optical absorption signatures]]<br />
<br />
===External Links===<br />
*[http://www.imo.org| International Maritime Organization] <br />
<br />
==References==<br />
<references/><br />
<br />
<br />
{{author <br />
|AuthorFullName= Veiga, Joana M<br />
|AuthorName=Username}}<br />
<br />
<br />
[[Category:Coastal and marine pollution]]<br />
[[Category:Maritime transportation]]<br />
[[Category:Theme 9]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=TBT_and_Imposex&diff=28210
TBT and Imposex
2009-03-11T16:09:56Z
<p>Wouter Kreiken: /* References */</p>
<hr />
<div>{{Revision}}<br />
This article describes the use of Tributyltin (TBT) in aquatic antifouling paints, its behaviour in the marine environment and one of its powerful negative effects in non-target species - the phenomenon of imposex in marine [[Gastropod|gastropods]] - which have led to the partial ban of this coumpound.<br />
<br />
<br />
===Introduction===<br />
Tributyltin (TBT) is a biocide compound which integrates certain antifouling paints used on the hulls of vessels to prevent biological fouling - a phenomenon which has considerable economic costs and environmental risks. Although very efficient, TBT has been subject to restrictions due to its [[Ecotoxicity|toxic effects]] in non-target species, detected at the end of the 1970s. One of this harmful effects is imposex – the masculinisation of females of certain marine snails in response of the exposure to TBT concentration, in the magnitude of ng.l-1. So far this phenomenon has been described for over 150 species. The sensitiveness and high correlation between the intensity of this phenomenon and the environmental concentrations of TBT allow the use of certain [[Gastropod|gastropod]] species as indicators of the degree of contamination in coastal zones. Though the use of TBT has been forbidden in many countries for vessels smaller than 25 m, the contamination levels are still a concern, particularly close to areas of intense boating and associated activities, such as fishing and commercial ports, marinas and dry-docks.<br />
<br />
===Why the need of antifoulings?===<br />
<br />
====The Problem of Fouling in Vessels====<br />
Any submersed rigid structure can work as substrate and be colonized by several marine organisms. It is estimated that there are over 4000 marine fouling species. In the case of vessels, the degree of fouling of the hull depends on the time of submersion, the time the vessel is immobilized or its speed, but mainly on the features of the marine environment. Without an antifouling protection, the fouling can reach 150 kg per square meter, in less than 6 months. This phenomenon leads to an increase in the weight of the vessel and the drag resistance of the hull surface, which directly affect the speed, manoverability and the fuel consumption (increasing up to 40%), leading to more frequent maintenance operations, higher costs and higher emissions of polluting gases. Additionally, the hulls can work as vectors of translocation of organisms from one place to another, increasing the risks of introducing non-native, [[invasive species]].<br />
[[Image:Fouling_boat.jpg|thumb|250px|left|Fouling on the hull of a small boat]]<br />
<br />
====Antifouling methods and TBT====<br />
The problem of fouling in vessels was recognised since the beginning of navigation. The ancient Phoenicians and Carthaginians were thought to have used copper sheathing and the Greeks and Romans both used lead sheathing on their ships’ hulls. More recent methods included the usage of paints containing organic compounds of lead, arsenic, mercury and halogens (''e.g.'' DDT) and copper oxide. The later is still widely used. <br />
The first antifouling paints using organic compounds of tin started appearing in the second half of the XX century and quickly dominated the markets during the following decades. Even today, TBT is globaly considered as the most effective solution developed so far to prevent fouling.<br />
<br />
====Sources and behaviour of TBT in aquatic systems====<br />
Antifouling systems represent the biggest and direct source of this pollutant. <br />
A TBT-based paint can be composed up to 3% of tin and a large commercial vessel can release more than 200g of TBT to the aquatic environment in only 3 days of permanence in a port.<br />
Aditionally, dry-docks and boatyards can also be relevant sources of antifouling paints (and other polutants), where old paint removal and repaint procedures take place. Most of the residues end up in the surrounding environment.<br />
<br />
When released into the water TBT can be degradated into less harmful forms by microrganisms and ultra-violet radiation. However, due to its high affinity to particles it will be easily transported to the sediments, where its concentration is typically higher than in the water. Here, organotin compounds are exceptionally stable and the concentration can remain high for a long time even after the sources have ceased.<br />
In the water, TBT can remain for a few days or months but in the sediments its half-life can extend for several months, years or even decades.<br />
<br />
[[Image:Boatyard antifouling.jpg|center|300px|Dry-docks and boatyards: Lack of proper containment during antifouling paint removal can result in deleterious substances being released into the aquatic environment.<br />
|frame]]<br />
<br />
===Effects in non-target species===<br />
<br />
====The case of the Bay of Arcachon (France)====<br />
During the period when TBT was being widely used as antifouling, the production of oisters in the Bay of Arcachon (France) almost collapsed. This coastal area is sumultaneasly a place of production of this shellfish and an area of intense recreative boating. Although the knowledge of TBT was very limited at the time, the French Authorities restricted the use of the compound in antifouling paints in the region, in a rare example of precautionary principle. Later on, it became clear that TBT was responsible for the failures in the reproduction and abnormal shell development of the oisters.<br />
<br />
[[Image:Dog_whelk_nucella_lapillus.jpg|thumb|250px|right|Dog whelk ''Nucella lapillus'']]<br />
<br />
====Imposex in marine snails====<br />
Also in the beginning of the 70’s certain reproductive abnormalities in other molluscs were discovered, which were later proved to result from exposure to TBT. In certain species of [[Gastropoda|gastropods]] with separate genders, the females presented a penis and/or vas deferens. The term “imposex” was given as “a superimposition of male features in females” and was first described in dog whelk (''Nucella lapillus''). Soon it was clear that this was a generalised phenomenon – not only all the populations of dog whelk analysed in southwest England were affected but worldwide the same phenomenon was reported and for different species of snails, particularly in areas of intense maritime traffic. So far, imposex and intersex (a similiar phenomenon) have been described in over 150 species of marine snails. More developed stages of imposex can lead to the sterilization and premature death of the females, affecting the entire population. However, the most dramatic aspect of this [[Endocrine disrupting compounds in the coastal environment|endocrine disruptor]] is the fact that TBT can act at extremely low concentrations: a few nanograms per litre is enough to trigger imposex in marine snails - the equivalent of 1 g of salt dissolved in a square pool of 100 m side and 100m depth!<br />
<br />
====Effects in other species====<br />
The knowledge of TBT, its toxicity and risks to non-target organisms, including humans, is still limited. However, studies suggest several harmful effects on the imune and neurological systems and embrios in mammals and described toxicity to plankton, algaes, fish and marine birds. It is known that top predators from marine [[Ecosystem|ecosystems]] can [[Bio-accumulation|accumulate]] significant amounts of [[Pollutant|pollutents]]. TBT is not an exception and has been already detected in [[Cetacean|cetaceans]] and seals, sharks and tunas.<br />
<br />
[[Image:imposex satges.jpg|thumb|300px|left|Schematic representation of the stages of imposex development in netted dog whelk (''Nassarius reticulatus'') (Barroso, 2001)]]<br />
<br />
===Monitoring of TBT contamination===<br />
<br />
====Imposex as an indicator of TBT contamination====<br />
Some species of snails have been used as bio-indicators to evaluate and compare the degree of TBT contamination in aquatic environments. They are suitable species since:<br />
*the stage of imposex reflects the amount of TBT present in the tissues of the organism and in the surrounding environment <br />
*the imposex is triggered by extremelly low concentrations – close to the level of detection of measuring instruments<br />
*marine snails can be very commun in certain habitats and have restricted mobility<br />
<br />
<br />
===Restrictions to TBT===<br />
Since 1988 the International Maritime Organization ([http://www.imo.org/ IMO]), through the Marine Environment Protection Committee (MEPC), has recognised the harmful effects of the antifouling systems, particularly TBT. In 1990 the MEPC recommended the IMO Member States to restrict the usage of TBT in boats smaller than 25m (as the recreation boating was considered to be the main direct input) and to establish maximum release rates for the antifouling paints. As the evidences of the negative impacts and toxicity of TBT increased, IMO adopted the International Convention on the Control of Harmful Anti-fouling Systems on Ships with the intention to globally ban TBT, starting in 2008. The ratification of this proposal was slow and though the number of joining countries has increased, the goals haven't been met.<br />
France, in 1982, was the first country to forbid the use of TBT in boats smaller that 25m, followed by the UK in 1987. The rest of the EU gradually joined the action. Japan has banned the organic compounds of tin from antifouling paints in 1990 and has called for a global ban. Other countries such as Switzerland, Austria and New Zealand voluntarily followed the IMO recomendation. Most developed countries have adopted legislation restricting the use of TBT and alternative methods are being used and developed.<br />
<br />
==See also==<br />
<br />
===Internal Links===<br />
*[[Coastal pollution and impacts]]<br />
*[[Endocrine disrupting compounds in the coastal environment]]<br />
*[[Pollution laws and regulations]]<br />
*[[Pollution indicators]]<br />
*[[Differentiation of major algal groups by optical absorption signatures]]<br />
<br />
===External Links===<br />
*[http://www.imo.org| International Maritime Organization] <br />
<br />
==References==<br />
<references/><br />
<br />
<br />
{{author <br />
|AuthorID=16893<br />
|AuthorFullName= Veiga, Joana M<br />
|AuthorName=Username}}<br />
<br />
<br />
[[Category:Coastal and marine pollution]]<br />
[[Category:Maritime transportation]]<br />
[[Category:Theme 9]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=TBT_and_Imposex&diff=28208
TBT and Imposex
2009-03-11T16:09:43Z
<p>Wouter Kreiken: /* References */</p>
<hr />
<div>{{Revision}}<br />
This article describes the use of Tributyltin (TBT) in aquatic antifouling paints, its behaviour in the marine environment and one of its powerful negative effects in non-target species - the phenomenon of imposex in marine [[Gastropod|gastropods]] - which have led to the partial ban of this coumpound.<br />
<br />
<br />
===Introduction===<br />
Tributyltin (TBT) is a biocide compound which integrates certain antifouling paints used on the hulls of vessels to prevent biological fouling - a phenomenon which has considerable economic costs and environmental risks. Although very efficient, TBT has been subject to restrictions due to its [[Ecotoxicity|toxic effects]] in non-target species, detected at the end of the 1970s. One of this harmful effects is imposex – the masculinisation of females of certain marine snails in response of the exposure to TBT concentration, in the magnitude of ng.l-1. So far this phenomenon has been described for over 150 species. The sensitiveness and high correlation between the intensity of this phenomenon and the environmental concentrations of TBT allow the use of certain [[Gastropod|gastropod]] species as indicators of the degree of contamination in coastal zones. Though the use of TBT has been forbidden in many countries for vessels smaller than 25 m, the contamination levels are still a concern, particularly close to areas of intense boating and associated activities, such as fishing and commercial ports, marinas and dry-docks.<br />
<br />
===Why the need of antifoulings?===<br />
<br />
====The Problem of Fouling in Vessels====<br />
Any submersed rigid structure can work as substrate and be colonized by several marine organisms. It is estimated that there are over 4000 marine fouling species. In the case of vessels, the degree of fouling of the hull depends on the time of submersion, the time the vessel is immobilized or its speed, but mainly on the features of the marine environment. Without an antifouling protection, the fouling can reach 150 kg per square meter, in less than 6 months. This phenomenon leads to an increase in the weight of the vessel and the drag resistance of the hull surface, which directly affect the speed, manoverability and the fuel consumption (increasing up to 40%), leading to more frequent maintenance operations, higher costs and higher emissions of polluting gases. Additionally, the hulls can work as vectors of translocation of organisms from one place to another, increasing the risks of introducing non-native, [[invasive species]].<br />
[[Image:Fouling_boat.jpg|thumb|250px|left|Fouling on the hull of a small boat]]<br />
<br />
====Antifouling methods and TBT====<br />
The problem of fouling in vessels was recognised since the beginning of navigation. The ancient Phoenicians and Carthaginians were thought to have used copper sheathing and the Greeks and Romans both used lead sheathing on their ships’ hulls. More recent methods included the usage of paints containing organic compounds of lead, arsenic, mercury and halogens (''e.g.'' DDT) and copper oxide. The later is still widely used. <br />
The first antifouling paints using organic compounds of tin started appearing in the second half of the XX century and quickly dominated the markets during the following decades. Even today, TBT is globaly considered as the most effective solution developed so far to prevent fouling.<br />
<br />
====Sources and behaviour of TBT in aquatic systems====<br />
Antifouling systems represent the biggest and direct source of this pollutant. <br />
A TBT-based paint can be composed up to 3% of tin and a large commercial vessel can release more than 200g of TBT to the aquatic environment in only 3 days of permanence in a port.<br />
Aditionally, dry-docks and boatyards can also be relevant sources of antifouling paints (and other polutants), where old paint removal and repaint procedures take place. Most of the residues end up in the surrounding environment.<br />
<br />
When released into the water TBT can be degradated into less harmful forms by microrganisms and ultra-violet radiation. However, due to its high affinity to particles it will be easily transported to the sediments, where its concentration is typically higher than in the water. Here, organotin compounds are exceptionally stable and the concentration can remain high for a long time even after the sources have ceased.<br />
In the water, TBT can remain for a few days or months but in the sediments its half-life can extend for several months, years or even decades.<br />
<br />
[[Image:Boatyard antifouling.jpg|center|300px|Dry-docks and boatyards: Lack of proper containment during antifouling paint removal can result in deleterious substances being released into the aquatic environment.<br />
|frame]]<br />
<br />
===Effects in non-target species===<br />
<br />
====The case of the Bay of Arcachon (France)====<br />
During the period when TBT was being widely used as antifouling, the production of oisters in the Bay of Arcachon (France) almost collapsed. This coastal area is sumultaneasly a place of production of this shellfish and an area of intense recreative boating. Although the knowledge of TBT was very limited at the time, the French Authorities restricted the use of the compound in antifouling paints in the region, in a rare example of precautionary principle. Later on, it became clear that TBT was responsible for the failures in the reproduction and abnormal shell development of the oisters.<br />
<br />
[[Image:Dog_whelk_nucella_lapillus.jpg|thumb|250px|right|Dog whelk ''Nucella lapillus'']]<br />
<br />
====Imposex in marine snails====<br />
Also in the beginning of the 70’s certain reproductive abnormalities in other molluscs were discovered, which were later proved to result from exposure to TBT. In certain species of [[Gastropoda|gastropods]] with separate genders, the females presented a penis and/or vas deferens. The term “imposex” was given as “a superimposition of male features in females” and was first described in dog whelk (''Nucella lapillus''). Soon it was clear that this was a generalised phenomenon – not only all the populations of dog whelk analysed in southwest England were affected but worldwide the same phenomenon was reported and for different species of snails, particularly in areas of intense maritime traffic. So far, imposex and intersex (a similiar phenomenon) have been described in over 150 species of marine snails. More developed stages of imposex can lead to the sterilization and premature death of the females, affecting the entire population. However, the most dramatic aspect of this [[Endocrine disrupting compounds in the coastal environment|endocrine disruptor]] is the fact that TBT can act at extremely low concentrations: a few nanograms per litre is enough to trigger imposex in marine snails - the equivalent of 1 g of salt dissolved in a square pool of 100 m side and 100m depth!<br />
<br />
====Effects in other species====<br />
The knowledge of TBT, its toxicity and risks to non-target organisms, including humans, is still limited. However, studies suggest several harmful effects on the imune and neurological systems and embrios in mammals and described toxicity to plankton, algaes, fish and marine birds. It is known that top predators from marine [[Ecosystem|ecosystems]] can [[Bio-accumulation|accumulate]] significant amounts of [[Pollutant|pollutents]]. TBT is not an exception and has been already detected in [[Cetacean|cetaceans]] and seals, sharks and tunas.<br />
<br />
[[Image:imposex satges.jpg|thumb|300px|left|Schematic representation of the stages of imposex development in netted dog whelk (''Nassarius reticulatus'') (Barroso, 2001)]]<br />
<br />
===Monitoring of TBT contamination===<br />
<br />
====Imposex as an indicator of TBT contamination====<br />
Some species of snails have been used as bio-indicators to evaluate and compare the degree of TBT contamination in aquatic environments. They are suitable species since:<br />
*the stage of imposex reflects the amount of TBT present in the tissues of the organism and in the surrounding environment <br />
*the imposex is triggered by extremelly low concentrations – close to the level of detection of measuring instruments<br />
*marine snails can be very commun in certain habitats and have restricted mobility<br />
<br />
<br />
===Restrictions to TBT===<br />
Since 1988 the International Maritime Organization ([http://www.imo.org/ IMO]), through the Marine Environment Protection Committee (MEPC), has recognised the harmful effects of the antifouling systems, particularly TBT. In 1990 the MEPC recommended the IMO Member States to restrict the usage of TBT in boats smaller than 25m (as the recreation boating was considered to be the main direct input) and to establish maximum release rates for the antifouling paints. As the evidences of the negative impacts and toxicity of TBT increased, IMO adopted the International Convention on the Control of Harmful Anti-fouling Systems on Ships with the intention to globally ban TBT, starting in 2008. The ratification of this proposal was slow and though the number of joining countries has increased, the goals haven't been met.<br />
France, in 1982, was the first country to forbid the use of TBT in boats smaller that 25m, followed by the UK in 1987. The rest of the EU gradually joined the action. Japan has banned the organic compounds of tin from antifouling paints in 1990 and has called for a global ban. Other countries such as Switzerland, Austria and New Zealand voluntarily followed the IMO recomendation. Most developed countries have adopted legislation restricting the use of TBT and alternative methods are being used and developed.<br />
<br />
==See also==<br />
<br />
===Internal Links===<br />
*[[Coastal pollution and impacts]]<br />
*[[Endocrine disrupting compounds in the coastal environment]]<br />
*[[Pollution laws and regulations]]<br />
*[[Pollution indicators]]<br />
*[[Differentiation of major algal groups by optical absorption signatures]]<br />
<br />
===External Links===<br />
*[http://www.imo.org| International Maritime Organization] <br />
<br />
==References==<br />
<references/><br />
<br />
<br />
{{author <br />
|AuthorID=16893<br />
|AuthorFullName= Veiga, Joana M<br />
|AuthorName=Username}}<br />
<br />
<br />
Category:Coastal and marine pollution<br />
[[Category:Maritime transportation]]<br />
[[Category:Theme 9]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Category:Articles_by_Veiga,_Joana_M&diff=28205
Category:Articles by Veiga, Joana M
2009-03-11T16:08:43Z
<p>Wouter Kreiken: New page: Articles By Joana Veiga:</p>
<hr />
<div>Articles By Joana Veiga:</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Template:This_weeks_featured_article&diff=27611
Template:This weeks featured article
2009-03-02T09:44:52Z
<p>Wouter Kreiken: /* US Army Corps of Engineers’ Coastal Programs */</p>
<hr />
<div>==US Army Corps of Engineers’ Coastal Programs==<br />
<br />
[[Image:USACE.jpg|thumb|350px|right|Figure 1: The United States Army Corps of Engineers (USACE) serves the Armed Forces and the Nation by providing vital engineering services and capabilities.]]<br />
<br />
The US Army Corps of Engineers (USACE) <ref>USACE Website http://www.usace.army.mil/</ref> is a federal agency within the Department of Defense mandated to provide both military and civil works services. In coastal regions, its primary roles include protecting and [[Overview of Coastal Habitat Protection and Restoration in the United States|restoring habitat]], maintaining navigable waters, conducting [[beach nourishment]], undertaking [[Flood (overflow)| flood control]] projects and regulating coastal restoration projects. <br />
<br />
The USACE’s military service dates to 1775. Its first water works project began in 1812. After the passage of the Rivers & Harbors Act of 1899, the USACE regulated activities in navigable waterways. Passage of the [http://www.epa.gov/watertrain/cwa/| Clean Water Act] in 1972 vastly increased the USACE’s authority over dredging and filling in waters and wetlands. The Corps is the lead federal flood control agency and a major provider of hydroelectric energy. In the late 1960s, the Corps became a leading environmental preservation and restoration agency. It is a leading partner in one of the largest restoration projects ever attempted—restoration of the hydrologic regime in the Florida Everglades.</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Template:This_weeks_featured_article&diff=27610
Template:This weeks featured article
2009-03-02T09:44:37Z
<p>Wouter Kreiken: US Army Corps of Engineers’ Coastal Programs</p>
<hr />
<div>==US Army Corps of Engineers’ Coastal Programs==<br />
<br />
[[Image:USACE.jpg|thumb|350px|center|Figure 1: The United States Army Corps of Engineers (USACE) serves the Armed Forces and the Nation by providing vital engineering services and capabilities.]]<br />
<br />
The US Army Corps of Engineers (USACE) <ref>USACE Website http://www.usace.army.mil/</ref> is a federal agency within the Department of Defense mandated to provide both military and civil works services. In coastal regions, its primary roles include protecting and [[Overview of Coastal Habitat Protection and Restoration in the United States|restoring habitat]], maintaining navigable waters, conducting [[beach nourishment]], undertaking [[Flood (overflow)| flood control]] projects and regulating coastal restoration projects. <br />
<br />
The USACE’s military service dates to 1775. Its first water works project began in 1812. After the passage of the Rivers & Harbors Act of 1899, the USACE regulated activities in navigable waterways. Passage of the [http://www.epa.gov/watertrain/cwa/| Clean Water Act] in 1972 vastly increased the USACE’s authority over dredging and filling in waters and wetlands. The Corps is the lead federal flood control agency and a major provider of hydroelectric energy. In the late 1960s, the Corps became a leading environmental preservation and restoration agency. It is a leading partner in one of the largest restoration projects ever attempted—restoration of the hydrologic regime in the Florida Everglades.</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Main_Page&diff=27609
Main Page
2009-03-02T09:44:08Z
<p>Wouter Kreiken: US Army Corps of Engineers’ Coastal Programs</p>
<hr />
<div><!----------------------------Introduction-----------------><br />
{| style="width:100%; border:2px solid #23297A; margin:0em 0em 1em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
|align="top"|<br />
<div style="font-size:100%; padding-bottom:0.15em;">Welcome to the [[Coastal Wiki|Coastal and Marine Wiki]], an Internet encyclopaedia of [[Special:Statistics|{{NUMBEROFARTICLES}}]] information pages for and by coastal professionals providing up-to-date high quality Coastal and Marine information. [[Coastal Wiki:Why, What and for Whom?|More about the Coastal and Marine Wiki]]</div><br />
|}<br />
<!----------------------End of introduction-----------------><br />
<br />
<!-----------------------Today's featured article, Did you know--------------------><br />
{|style="border-spacing:8px; margin:0px -8px;"<br />
|class="MainPageBG" style="width:70%; border:1px solid #23297A; background:#f5faff; vertical-align:top; color:#000;"|<br />
{|width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">This months featured article</h2><br />
|-<br />
|style="color:#000;"| <br />
<br />
{{Template:This_weeks_featured_article}} [[US Army Corps of Engineers’ Coastal Programs|'''More..''']]<br />
<br />
|-<br />
! <br />
|-<br />
|}<!----------------------------------Categories---------------------><br />
|class="MainPageBG" style="width:30%; border:1px solid #23297A; background:#f5faff; vertical-align:top"|<br />
{| width="100%" cellpadding="2" cellspacing="5" style="vertical-align:top; background:#f5faff;"<br />
!<br />
<br />
<h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b1bf; text-align:left; color:#000; padding:0.2em 0.4em;">Categories</h2><br />
|-<br />
|-<br />
|style="width:15em; vertical-align:right; font-weight:bold;"|<br />
[[Image:natural_bis.gif|natural.gif]] [[:Category:Coastal and marine natural environment|Natural environment]]<br><br><br />
[[Image:human_bis.gif|human4.gif]] [[:Category:Coastal and marine human activities|Human activities]]<br><br><br />
[[Image:impacts_bis.gif|impacts.gif]] [[:Category:Coastal and marine issues and impacts|Issues and impacts]]<br><br><br />
[[Image:earth_bis.gif|earth2.gif]] [[:Category:Coastal and marine areas and locations|Areas and locations]]<br><br><br />
[[Image:management-bis.gif|Management.gif]] [[:Category:Coastal management|Coastal management]]<br><br><br />
[[Image:people_bis.gif|people.gif]] [[:Category:People and organisations in coastal management|People and organisations ]] <br />
|}<br />
|}<br />
{{#categorytree:Coastal and marine system|mode=pages|onlyroot=on|style=border:1px solid gray; padding:0.7ex; vertical-align:right; background-color:#f5faff;}}<br />
<br><br />
'''Welcome to the Coastal Wiki, your guide to coastal knowledge and experience'''<br><br />
You may find information on any coastal topic by entering a corresponding term in the search window. “Go” will direct you to an article with this title (if such an article exists); “Search” will provide an overview of articles in which your search term appears. You will find an explanation of coastal terms and concepts in the [[Glossary]].<br />
<br />
We also invite coastal and marine practitioners, policymakers and scientists to make a contribution to this new concept in sharing European knowledge and experience in integrated coastal zone management. You may contribute in several ways: you may improve or update an existing article, you may add a discussion page to an existing article or you may add a new topic.<br />
<br><br><br />
<br />
'''How to contribute to the Coastal Wiki'''<br><br />
You have unrestricted access to the Coastal Wiki. But for adding or editing articles an authorisation is required. This is a major difference with the general wikipedia. For obtaining an editing authorisation you may contact your [http://www.encora.eu/networks.php national coordination office] or you may simply send an email to info@encora.eu. You will receive a request to provide contact information for the Wiki Contact Database. Anonymous contributions to the Coastal Wiki are precluded. Authors, co-authors and editors of articles are explicitly acknowledged. Your contribution will be reviewed by the coordinator of the theme where your article best fits. The theme coordinators also check that your contribution is [[links|adequately linked]] to existing articles on similar or related topics. <br />
<br />
You should remember that the Coastal Wiki is primarily meant for disseminating knowledge to a broader audience than the circles of specialists working at the frontiers of science. It is not meant for publishing original research; it is a vehicle for disseminating knowledge complementary to the traditional peer-reviewed scientific journals. Please read the [[Basic setup, rules and guidelines]] and [[How to edit an article]] before you start writing an article.<br />
<br><br><br />
<!------------------------------10 themes-----------------><br />
{|border=1 style="border:2px #23297A solid; background:#f5faff;" width="688px" cellspacing="0" cellpadding="0" <br />
|cellspacing="0" style="border-bottom:1px solid #23297A; background:#cee0f2; font-size:150%" colspan=2 align=center height=30px|Encora Themes<br />
|-<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign="top" style="border-right:1px solid #23297A"|[[Image:Theme01_40.png|Theme 1 : Social and economic aspects of ICZM Multifunctionality and Valuation.]]||<br />
'''[[Theme 1]] - Social and economic aspects of ICZM Multifunctionality and Valuation.'''<br><br />
Valuation of competing functions to optimise the societal use of coastal and marine resources.<br />
|}<br />
<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme02_40.png|Theme 2 : ICZM Participation and Implementation.]]||<br />
'''[[Theme 2]] - ICZM Participation and Implementation.''' <br><br />
Testing and improving methods to evaluate progress in the implementation of ICZM, including eGovernance. <br><br />
|}<br />
|-<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme03_40.png|Theme 3 : Coastal and marine spatial planning.]]||<br />
'''[[Theme 3]] - Coastal and marine spatial planning.''' <br><br />
Multiple-scale structuring of spatial coastal and marine planning and related decision-support systems for sustainable development. <br><br />
|}<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="102px" valign=center style="border-right:1px solid #23297A"|[[Image:Theme04_40.png|Theme 4 : Pollution, prevention and mitigation.]]||<br />
'''[[Theme 4]] - Pollution, prevention and mitigation.''' <br><br />
Development and application of emerging methodologies for preventing, detecting and mitigating pollution and for identification of areas at risk. <br><br />
|}<br />
|-<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme05_40.png|Theme 5 : Long-term geomorphological change and climate impacts.]]||<br />
'''[[Theme 5]] - Long-term geomorphological change and climate impacts.'''<br><br />
Promoting development, demonstration & dissemination of new and emerging models & methodologies for prediction of changes to coastal systems.<br><br />
|}<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme06_40.png| Theme 6 : Effect of development and use on eco-morphology and coastal habitats.]]||<br />
'''[[Theme 6]] - Effect of development and use on eco-morphology and coastal habitats.'''<br><br />
Impact-assessment tools and environmental techniques for recovery of coastal habitats.<br><br />
|}<br />
|-<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme07_40.png|Theme 7|Theme 7 Biodiversity of coastal and marine habitats and ecosystems]]||<br />
'''[[Theme 7 Biodiversity of coastal and marine habitats and ecosystems|Theme 7]] - Assessment of biodiversity change.''' <br><br />
Testing and improving an ecological valuation protocol for the coastal and marine environment, including transitional waters. <br><br />
|}<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme08_40.png|Theme 8 : New sustainable coastal engineering techniques.]]||<br />
'''[[Theme 8]] - New sustainable coastal engineering techniques.''' <br><br />
Cataloguing innovative coastal engineering techniques to solve practical coastal protection issues. <br><br />
|}<br />
|-<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme09_40.png|Theme 9 : Assessment of field observation techniques.]]||<br />
'''[[Theme 9]] - Assessment of field observation techniques.''' <br><br />
New and emerging tools and practices for coastal and marine observation, with focus on remote sensing and remotely controlled measuring devices. <br><br />
|}<br />
|<br />
{|style="background:transparent;" cellspacing=0 cellpadding="5" width=100%<br />
|-valign="top"<br />
|width="100px" valign=top style="border-right:1px solid #23297A"|[[Image:Theme10_40.png| Theme 10 : Capacity Building, Training and Education.]]||<br />
'''[[Theme 10]] - Capacity Building, Training and Education. ''' <br><br />
Comparative assessment of ICZM training and education programmes. <br><br />
|}<br />
|}<br />
<!------------------------------end of 10 themes-----------------><br />
<br><br />
<!------------------------------Bottom table---------------------><br />
{| style=" width:100%; border:1px solid #23297A; margin:0em 0em 1em 0em; background:#f9f9f9;" cellspacing="5" cellpadding="0"<br />
<br />
|style="width:25%"| [[Help:Contents|'''Help pages''']] <br />
|style="width:25%"|[[glossary|'''Glossary''']] <br />
|style="width:25%"| [[Special:Popularpages|'''Popular pages''']] <br />
|style="width:25%" align="right"| [[Articles that need expanding|'''Articles that need expanding''']]<br />
<br />
|}<br />
<!------------------------------end of Bottom table---------------------></div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Contingent_Valuation_Method&diff=27536
Contingent Valuation Method
2009-02-27T15:06:50Z
<p>Wouter Kreiken: </p>
<hr />
<div>The '''Contingent Valuation Method''' (CVM) is an economic, non-market based valuation method especially used to infer individual’s preferences for public goods, notably environmental quality. For this same reason, CVM is known in the literature by exploring the use of questionnaires and asking directly consumers, i.e. respondents, for their maximum willingness to pay (WTP) for specified improvements in the environmental quality, including protection of marine [[biodiversity]]. In short, CVM circumvents the absence of markets for public goods by presenting consumers with a survey market in which they have the opportunity to buy the good in question – protection of marine [[biodiversity]]. Because the elicited WTP values are contingent upon the market described to the respondents, this approach came to be called the contingent valuation method. <br />
<br />
==Introduction==<br />
The survey market should be modelled after a political market, notably in a referendum format. In other words, respondents should be asked how they would vote (favour or against) upon a described marine environmental protection program, taking into account that its approval would imply the payment of a tax. For each if the protection program refers to the introduction of a [[ballast water]] treatment complex in European harbours one could model the WTP question as follows: “''If the total tax amount to be paid for the water treatment complex was 30 Euro per year for the next 2 years, and thus keeping European coast free from exotic [[algae]] and the beaches free from [[algae foams]], how would you vote on the introduction this tax?''” Bearing in mind the answer of the respondents to this question and the use of appropriated econometric tools, economists are able assess the individual demand for environmental quality and thus quantify in monetary terms the underlying welfare changes. The typical CVM survey consists of three sections. <br />
<br />
The first section is '''characterized by the description of the environmental change''' as conveyed by the policy formulation and the description of the contingent market. The policy formulation involves describing the availability (or quality) of the environmental commodity in both the ‘reference state’ (usually the status quo) and ‘target state’ (usually depicting the policy action). Since all monetary transactions occur in a social context, it is also crucial to define the contingent market - most of the time rather unfamiliar to the respondents - by stating to the respondent both the rules specifying the conditions that would lead to policy implementation as well the payment to be exacted from the respondent’s household in the event of policy implementation. <br />
<br />
The second section is where the '''respondent is asked to state her monetary valuation for the described policy formulation'''. This part is the core of the questionnaire. The major objective of this section is to obtain a monetary measure of the maximum Willingness to Pay that the individual consumers are willing to pay for the described environmental policy action. <br />
<br />
The third section of the CVM instrument is a set of '''questions that collect socio-demographic information about the respondents'''. The answers to these questions help to better characterise the respondent’s profile and are used to understand the respondent’s stated WTP responses. The third section finishes with follow-up questions. The follow-up questions are answered by the interviewers. The goal is to assess whether the respondents have (well) understood the CVM survey in general, and the valuation question in particular see [[#A brief history of contingent valuation|A brief history of contingent valuation]] for more details on the practice of this method.<br />
<br />
Today, the CVM is one of the most used techniques for valuation of environmental benefits, widely used by academic institutions as well as by governmental agencies as a crucial tool in cost-benefit analysis and damage cost assessment [[#The National Oceanic Atmospheric Administration Panel|(see NOAA Panel for more technical details on how to construct an efficient survey)]]. This is partly due to the advantages of CVM compared to other valuation methods. First, the CVM method gives immediately a monetary assessment of respondents’ preferences. Second, the CVM method is the only valuation technique that is capable of shedding light on the monetary valuation of the non-use values, i.e., the benefit value component of the environmental commodity that is not directly associated with its direct use or consumption. These values are characterized by having no behavioural market trace. Therefore, economists cannot glean information about these values relying on market-based valuation approaches. For environmental resources such as the protection of natural parks or [[biodiversity]] sensitive areas, which play an important role in guaranteeing the protection of local wildlife diversity, the non-use value component may account for the major part of the conservation benefits. Ignoring such values will be responsible for a systematic bias in the estimation (an underestimation) of the total economic value of the related environment. Third, CVM brings with it the advantage that environmental quality changes may be valued even if they have not yet occurred (ex ante valuation). This implies that the CVM can be a useful advisory tool for policy decision-making. Furthermore, the constructed nature of the CVM method permits to value environmental changes even if they have not yet occurred. Therefore, CVM offers a greater potential scope and flexibility than the revealed preference methods since it is possible to specify different states of nature (policy scenarios) that may even lie outside the current institutional arrangements or levels of provision.<br />
<br />
==A brief history of contingent valuation==<br />
The first CVM published reference dates from 1947. We refer to the Ciriacy-Wantrup<ref>Ciriacy-Wantrup (1947) “Capital Returns from Soil Conservation Practices”, Journal of Farms Economics, 29, 1180-1190.</ref> article published in the Journal of Farms Economics. The study focuses on the valuation of the economic effects of preventing soil [[erosion]]. The author suggested that one way to obtain information on the demand for these favourable effects would be to ask directly the individuals how much they would be willing to pay for successive increments. However, no empirical valuation was attempted. However, the first CVM design and implementation only occurred two decades later when Robert Davis assessed the economic value of the recreational possibilities of the Maine Woods by exploring the survey technique (Davis 1963<ref>DAVIS, Robert K. (1963)"The Value of Outdoor Recreation: An Economic Study of the Maine Woods" Ph.D. dissertation. Harvard University</ref>). Davis simulated a market behaviour situation by putting the interviewer in the “''position of a seller who elicits the highest possible bid from the users of the services being offered''”. <br />
<br />
Since these early beginnings, the CVM has been used to measure benefits of a wide range of environmental goods including recreation, amenity value, scenery, forests, [[wetlands]], wildlife, air and water quality. More recently, there has been a trend to conduct CVM studies not only to value environmental goods, but also to investigate the various methodological issues involved in the valuation exercise, including the study of the impact of consumer’s attitudes, motivations on CVM estimates. Furthermore, throughout these decades, the CVM has gone through several phases, emerging from the academy into the rough and tumble of the outside world. Strong development stimulus was given by the [http://en.wikisource.org/wiki/Executive_Order_12291 Reagan Executive Order 12291], introduced in 1981; the re-interpretation of CERCLA, in 1989; the Exxon Valdez damage assessment, in 1992, and, more recently, the NOAA panel<ref>NOAA – National Oceanic and Atmospheric Administration (1993) “Report of the NOAA Panel on Contingent Valuation”, Federal Register, Vol 58, no. 10, US, 4601-4614.</ref>.<br />
<br />
===The Reagan Executive Order ===<br />
The [http://en.wikisource.org/wiki/Executive_Order_12291 Reagan Executive Order 12291], introduced in 1981, constitutes a strong stimulus for the development of the monetary valuation methods of environmental commodities. In concrete terms, the Executive Order stipulated that all federal regulations on environmental policy should be submitted to a cost-benefit analysis. All regulations, including both the promulgation of new regulations and the review of the existing ones, would only be carried out if a positive present value for the society could be achieved. Therefore, the social benefits had to be monetized. The flexibility and generality of CVM’s application was the main reason why this valuation method received most of the [http://www.epa.gov/ EPA]’s “demands” in the monetary assessment of the social costs and benefits associated with the new regulations on environmental policy. Thus, the appearance of Executive Order 12291 had a major impact in the development of the CVM. Furthermore, the District of Columbia Court of Appeals re-interpretation in 1989 of the [http://www.epa.gov/superfund/policy/cercla.htm US Comprehensive Environmental Response, Compensation and Liability Act] of 1980 (USDI 1989) expressed not only the legitimacy of non-use values as a component of the total resource value, but also granted equal standing to stated and revealed preferences evaluation techniques. Such a governmental decision was responsible for the expansion of the CVM beyond the academic world, now fully recognized as a fair, conventional method to shed light on the economic value of environmental quality, corner stone of an efficient, well accepted policy design.<br />
<br />
===Exxon Valdez oil spill===<br />
Another important benchmark in the history of the CVM is the massive [[oil spills|oil spill]] due to the grounding of the oil tanker [[http://www.encora.eu/coastalwiki/North_Sea_pollution_from_shipping:_legal_framework#Accidental_pollution|Exxon Valdez]] in the Prince William Sound in the Northern part of the Gulf of Alaska on March 24, 1989. This [[oil spills|oil spill]] was the largest [[oil spills|oil spill]] from a tanker in US history: more than 1,300 kilometres of coastline were affected and almost 23,000 birds were killed. After the [[oil spills|oil spill]], the State of Alaska commissioned various studies to identify the physical damage to the natural resources. The follow-up economic damage assessment studies also take into account, in addition to water purification costs, economic losses such as the decrease in revenue from recreation and fisheries. Moreover, the State of Alaska appointed an interdisciplinary group of researchers to design and implement a national CVM study to measure the loss of non - use values to US citizens as a result of the [[oil spills|oil spill]]. This study was coordinated by Richard Carson and constitutes one of the major contingent valuation applications and represents an important methodological reference for all contingent valuation researchers' work. The loss of non - use values resulting from the Exxon Valdez oil spill was estimated at 2,8 billion dollars. <br />
<br />
However, and anticipating these high financial consequences, Exxon commissioned a group of researchers to verify whether non - use values could be accurately measured by means of CVM. The main argument of critics of CVM is that this method is not capable of resulting in valid and reliable monetary measures of non-use values. Hausman’s well-know argument “is some number better than no number”<ref>Diamon, P.A.; Hausman, J.A. (1994) Contingent Valuation: Is Some Number better than No Number? The Journal of Economic Perspectives, Vol. 8, No. 4. (Autumn, 1994), pp. 45-64.</ref> fully expresses the scepticism toward the CVM method. Therefore, according to Hausman, assessments of lost non-use values by means of the CVM method should not be used in court. In order to address Hausman’s critique, the National Oceanic and Atmospheric Administration set a group of experts in order to evaluate the reliability of the use of CVM in the natural resource damage assessments.<br />
<br />
==The National Oceanic and Atmospheric Administration Panel==<br />
A panel of experts, with the Nobel Laureates Kenneth Arrow and Robert Solow as chairmen, provided advice to the [http://www.noaa.gov/ National Oceanic and Atmospheric Administration], (NOAA) on the following question: “is the contingent valuation method capable of providing estimates of lost non - use or existence values that are reliable enough to be used in the natural resource damage assessments?” The final advice of the NOAA panel may be summarised by the following sentence:<br />
<br />
:"''... the Panel concludes that well conducted CVM studies can produce estimates reliable enough to be the starting point of a judicial process of damage assessment, including lost passive values.''" <ref>NOAA, Federal Register, Vol. 58, No. 10, page 4610</ref> <br />
This conclusion cheered all researchers who wish to use the contingent valuation. However, the Panel was rather prudent with its conclusion and qualified such a statement by establishing a set of guidelines, recommended to all future CVM applications, concerning the design and execution of the survey instrument. The six most important guidelines, also well known as the six pillars of the NOAA, are summarised as follows:<br />
# CVM should rely on face-to-face interviews rather than telephone interviews, and whenever this is not possible (specially because of the high costs associated with the personal interviews) telephone interviews are preferable to mail surveys;<br />
# CVM should elicit the respondent’s WTP to prevent a future incident rather than WTA (Willingness to Accept) for an incident already occurred;<br />
# CVM should use a dichotomous choice referendum elicitation format, i.e., the respondents should be asked how they would vote (favour or against) upon a described environmental quality change. The main reason for the dichotomous choice is that such a take-it-or-leave-it survey valuation question is more likely to reflect real daily world market decisions which individuals are confronted with. Moreover, the dichotomous choice referendum reveals itself to be less vulnerable to strategic bidding behaviour than, for example, the open ended elicitation format; <br />
# CVM should contain an accurate and understandable description of the program or policy under consideration and the associated environmental benefits in each of the two scenarios, i.e., with and without the policy. Interdisciplinary work with other research areas, namely the biological sciences, is recommended;<br />
# CVM should include reminders of the substitutes for the commodity in question as well as its budget. In a context where the respondents are being asked how they would vote on a financial contribution to protect a natural area, the respondents should be reminded of the existence of the other areas that exist. Moreover the respondent should be reminded that such contribution would reduce the amount of money that he or she has available to spend on other things. The major idea here is to make such a (hypothetical) valuation exercise resemble as closely as possible an actual market transaction;<br />
# CVM experiments should include a follow-up section at the end of the questionnaire to be sure if the respondents understood (or not) the choice that they were asked to make.<br />
<br />
==References==<br />
<references/><br />
<br />
==Further reading==<br />
:Carson, R. T., R. C. Mitchell, W. M. Hanemann, R. J. Kopp, S. Presser and P. A. Ruud (1992) “A Contingent Valuation Study of Lost Passive Use Values Resulting from the Exxon Valdez Oil Spill”, Report prepared for the Attorney General of the State of Alaska, Washington. (Carson et al. 1992)<br />
:Loureiro, M. L., J.B. Loomis and M.X. Vázquez (2007) “[http://www.encora.eu/coastalwiki/Impacts_from_maritime_transport Estimating the Non-Market Environmental Damages caused by the Prestige Oil Spill]”, IDEGA-Universidade de Santiago de Compostela, working paper.<br />
:Mitchell, R. C. and R. T. Carson (1989) “Using Surveys to Value Public Goods. The Contingent Valuation Method]”, Washington DC, Resources for the Future. <br />
:Nunes, P.A.L.D. and A. de Blaeij (2005) “Economic Assessment of Marine Quality Benefits: Applying the Use of Non-Market Valuation Methods”, in Maes, Frank (Ed.), Marine Resource Damage Assessment, Liability and Compensation for Environmental Damage, Chapter 7, Springer Publishers, Amsterdam, The Netherlands. <br />
:Nunes, P.A.L.D. and J.C.J.M. van den Bergh (2004) “Valuing non-market benefits for protection against exotic marine species in the Netherlands using TC and CV data”, Environment and Resource Economics, 28, pp. 517-532.<br />
:Nunes, P.A.L.D. and P. Nijkamp (2007) “Contingent Valuation Method” in M. Deakin, G. Mitchell, P. Nijkamp and R. Vreeker (Eds.), Sustainable Urban Development (Volume 2): The Environmental Assessment Methods, Chapter 8, Routledge, UK. <br />
:Nunes, P.A.L.D. (2002) “The Contingent Valuation of Natural Parks: Assessing the Warmglow Propensity Factor” Edward Elgar Publishing (UK), New Horizons in Environmental Economics Series. <br />
:Nunes, P.A.L.D. and E. Schokkaert (2003) “Identifying the warm glow effect in contingent valuation”, Journal of Environmental Economics and Management, vol. 45, 231-245.<br />
<br />
{{author<br />
|AuthorID=11621<br />
|AuthorFullName=Paulo A. L. D. Nunes<br />
|AuthorName=Pnunes}}<br />
<br />
[[Category:Theme_1]]<br />
[[Category:Coastal management]]<br />
[[Category:Evaluation and assessment in coastal management]]<br />
[[Category:Techniques and methods in coastal management]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Contingent_Valuation_Method&diff=27535
Contingent Valuation Method
2009-02-27T15:06:32Z
<p>Wouter Kreiken: /* Introduction */</p>
<hr />
<div>{{Links}}<br />
<br />
The '''Contingent Valuation Method''' (CVM) is an economic, non-market based valuation method especially used to infer individual’s preferences for public goods, notably environmental quality. For this same reason, CVM is known in the literature by exploring the use of questionnaires and asking directly consumers, i.e. respondents, for their maximum willingness to pay (WTP) for specified improvements in the environmental quality, including protection of marine [[biodiversity]]. In short, CVM circumvents the absence of markets for public goods by presenting consumers with a survey market in which they have the opportunity to buy the good in question – protection of marine [[biodiversity]]. Because the elicited WTP values are contingent upon the market described to the respondents, this approach came to be called the contingent valuation method. <br />
<br />
==Introduction==<br />
The survey market should be modelled after a political market, notably in a referendum format. In other words, respondents should be asked how they would vote (favour or against) upon a described marine environmental protection program, taking into account that its approval would imply the payment of a tax. For each if the protection program refers to the introduction of a [[ballast water]] treatment complex in European harbours one could model the WTP question as follows: “''If the total tax amount to be paid for the water treatment complex was 30 Euro per year for the next 2 years, and thus keeping European coast free from exotic [[algae]] and the beaches free from [[algae foams]], how would you vote on the introduction this tax?''” Bearing in mind the answer of the respondents to this question and the use of appropriated econometric tools, economists are able assess the individual demand for environmental quality and thus quantify in monetary terms the underlying welfare changes. The typical CVM survey consists of three sections. <br />
<br />
The first section is '''characterized by the description of the environmental change''' as conveyed by the policy formulation and the description of the contingent market. The policy formulation involves describing the availability (or quality) of the environmental commodity in both the ‘reference state’ (usually the status quo) and ‘target state’ (usually depicting the policy action). Since all monetary transactions occur in a social context, it is also crucial to define the contingent market - most of the time rather unfamiliar to the respondents - by stating to the respondent both the rules specifying the conditions that would lead to policy implementation as well the payment to be exacted from the respondent’s household in the event of policy implementation. <br />
<br />
The second section is where the '''respondent is asked to state her monetary valuation for the described policy formulation'''. This part is the core of the questionnaire. The major objective of this section is to obtain a monetary measure of the maximum Willingness to Pay that the individual consumers are willing to pay for the described environmental policy action. <br />
<br />
The third section of the CVM instrument is a set of '''questions that collect socio-demographic information about the respondents'''. The answers to these questions help to better characterise the respondent’s profile and are used to understand the respondent’s stated WTP responses. The third section finishes with follow-up questions. The follow-up questions are answered by the interviewers. The goal is to assess whether the respondents have (well) understood the CVM survey in general, and the valuation question in particular see [[#A brief history of contingent valuation|A brief history of contingent valuation]] for more details on the practice of this method.<br />
<br />
Today, the CVM is one of the most used techniques for valuation of environmental benefits, widely used by academic institutions as well as by governmental agencies as a crucial tool in cost-benefit analysis and damage cost assessment [[#The National Oceanic Atmospheric Administration Panel|(see NOAA Panel for more technical details on how to construct an efficient survey)]]. This is partly due to the advantages of CVM compared to other valuation methods. First, the CVM method gives immediately a monetary assessment of respondents’ preferences. Second, the CVM method is the only valuation technique that is capable of shedding light on the monetary valuation of the non-use values, i.e., the benefit value component of the environmental commodity that is not directly associated with its direct use or consumption. These values are characterized by having no behavioural market trace. Therefore, economists cannot glean information about these values relying on market-based valuation approaches. For environmental resources such as the protection of natural parks or [[biodiversity]] sensitive areas, which play an important role in guaranteeing the protection of local wildlife diversity, the non-use value component may account for the major part of the conservation benefits. Ignoring such values will be responsible for a systematic bias in the estimation (an underestimation) of the total economic value of the related environment. Third, CVM brings with it the advantage that environmental quality changes may be valued even if they have not yet occurred (ex ante valuation). This implies that the CVM can be a useful advisory tool for policy decision-making. Furthermore, the constructed nature of the CVM method permits to value environmental changes even if they have not yet occurred. Therefore, CVM offers a greater potential scope and flexibility than the revealed preference methods since it is possible to specify different states of nature (policy scenarios) that may even lie outside the current institutional arrangements or levels of provision.<br />
<br />
==A brief history of contingent valuation==<br />
The first CVM published reference dates from 1947. We refer to the Ciriacy-Wantrup<ref>Ciriacy-Wantrup (1947) “Capital Returns from Soil Conservation Practices”, Journal of Farms Economics, 29, 1180-1190.</ref> article published in the Journal of Farms Economics. The study focuses on the valuation of the economic effects of preventing soil [[erosion]]. The author suggested that one way to obtain information on the demand for these favourable effects would be to ask directly the individuals how much they would be willing to pay for successive increments. However, no empirical valuation was attempted. However, the first CVM design and implementation only occurred two decades later when Robert Davis assessed the economic value of the recreational possibilities of the Maine Woods by exploring the survey technique (Davis 1963<ref>DAVIS, Robert K. (1963)"The Value of Outdoor Recreation: An Economic Study of the Maine Woods" Ph.D. dissertation. Harvard University</ref>). Davis simulated a market behaviour situation by putting the interviewer in the “''position of a seller who elicits the highest possible bid from the users of the services being offered''”. <br />
<br />
Since these early beginnings, the CVM has been used to measure benefits of a wide range of environmental goods including recreation, amenity value, scenery, forests, [[wetlands]], wildlife, air and water quality. More recently, there has been a trend to conduct CVM studies not only to value environmental goods, but also to investigate the various methodological issues involved in the valuation exercise, including the study of the impact of consumer’s attitudes, motivations on CVM estimates. Furthermore, throughout these decades, the CVM has gone through several phases, emerging from the academy into the rough and tumble of the outside world. Strong development stimulus was given by the [http://en.wikisource.org/wiki/Executive_Order_12291 Reagan Executive Order 12291], introduced in 1981; the re-interpretation of CERCLA, in 1989; the Exxon Valdez damage assessment, in 1992, and, more recently, the NOAA panel<ref>NOAA – National Oceanic and Atmospheric Administration (1993) “Report of the NOAA Panel on Contingent Valuation”, Federal Register, Vol 58, no. 10, US, 4601-4614.</ref>.<br />
<br />
===The Reagan Executive Order ===<br />
The [http://en.wikisource.org/wiki/Executive_Order_12291 Reagan Executive Order 12291], introduced in 1981, constitutes a strong stimulus for the development of the monetary valuation methods of environmental commodities. In concrete terms, the Executive Order stipulated that all federal regulations on environmental policy should be submitted to a cost-benefit analysis. All regulations, including both the promulgation of new regulations and the review of the existing ones, would only be carried out if a positive present value for the society could be achieved. Therefore, the social benefits had to be monetized. The flexibility and generality of CVM’s application was the main reason why this valuation method received most of the [http://www.epa.gov/ EPA]’s “demands” in the monetary assessment of the social costs and benefits associated with the new regulations on environmental policy. Thus, the appearance of Executive Order 12291 had a major impact in the development of the CVM. Furthermore, the District of Columbia Court of Appeals re-interpretation in 1989 of the [http://www.epa.gov/superfund/policy/cercla.htm US Comprehensive Environmental Response, Compensation and Liability Act] of 1980 (USDI 1989) expressed not only the legitimacy of non-use values as a component of the total resource value, but also granted equal standing to stated and revealed preferences evaluation techniques. Such a governmental decision was responsible for the expansion of the CVM beyond the academic world, now fully recognized as a fair, conventional method to shed light on the economic value of environmental quality, corner stone of an efficient, well accepted policy design.<br />
<br />
===Exxon Valdez oil spill===<br />
Another important benchmark in the history of the CVM is the massive [[oil spills|oil spill]] due to the grounding of the oil tanker [[http://www.encora.eu/coastalwiki/North_Sea_pollution_from_shipping:_legal_framework#Accidental_pollution|Exxon Valdez]] in the Prince William Sound in the Northern part of the Gulf of Alaska on March 24, 1989. This [[oil spills|oil spill]] was the largest [[oil spills|oil spill]] from a tanker in US history: more than 1,300 kilometres of coastline were affected and almost 23,000 birds were killed. After the [[oil spills|oil spill]], the State of Alaska commissioned various studies to identify the physical damage to the natural resources. The follow-up economic damage assessment studies also take into account, in addition to water purification costs, economic losses such as the decrease in revenue from recreation and fisheries. Moreover, the State of Alaska appointed an interdisciplinary group of researchers to design and implement a national CVM study to measure the loss of non - use values to US citizens as a result of the [[oil spills|oil spill]]. This study was coordinated by Richard Carson and constitutes one of the major contingent valuation applications and represents an important methodological reference for all contingent valuation researchers' work. The loss of non - use values resulting from the Exxon Valdez oil spill was estimated at 2,8 billion dollars. <br />
<br />
However, and anticipating these high financial consequences, Exxon commissioned a group of researchers to verify whether non - use values could be accurately measured by means of CVM. The main argument of critics of CVM is that this method is not capable of resulting in valid and reliable monetary measures of non-use values. Hausman’s well-know argument “is some number better than no number”<ref>Diamon, P.A.; Hausman, J.A. (1994) Contingent Valuation: Is Some Number better than No Number? The Journal of Economic Perspectives, Vol. 8, No. 4. (Autumn, 1994), pp. 45-64.</ref> fully expresses the scepticism toward the CVM method. Therefore, according to Hausman, assessments of lost non-use values by means of the CVM method should not be used in court. In order to address Hausman’s critique, the National Oceanic and Atmospheric Administration set a group of experts in order to evaluate the reliability of the use of CVM in the natural resource damage assessments.<br />
<br />
==The National Oceanic and Atmospheric Administration Panel==<br />
A panel of experts, with the Nobel Laureates Kenneth Arrow and Robert Solow as chairmen, provided advice to the [http://www.noaa.gov/ National Oceanic and Atmospheric Administration], (NOAA) on the following question: “is the contingent valuation method capable of providing estimates of lost non - use or existence values that are reliable enough to be used in the natural resource damage assessments?” The final advice of the NOAA panel may be summarised by the following sentence:<br />
<br />
:"''... the Panel concludes that well conducted CVM studies can produce estimates reliable enough to be the starting point of a judicial process of damage assessment, including lost passive values.''" <ref>NOAA, Federal Register, Vol. 58, No. 10, page 4610</ref> <br />
This conclusion cheered all researchers who wish to use the contingent valuation. However, the Panel was rather prudent with its conclusion and qualified such a statement by establishing a set of guidelines, recommended to all future CVM applications, concerning the design and execution of the survey instrument. The six most important guidelines, also well known as the six pillars of the NOAA, are summarised as follows:<br />
# CVM should rely on face-to-face interviews rather than telephone interviews, and whenever this is not possible (specially because of the high costs associated with the personal interviews) telephone interviews are preferable to mail surveys;<br />
# CVM should elicit the respondent’s WTP to prevent a future incident rather than WTA (Willingness to Accept) for an incident already occurred;<br />
# CVM should use a dichotomous choice referendum elicitation format, i.e., the respondents should be asked how they would vote (favour or against) upon a described environmental quality change. The main reason for the dichotomous choice is that such a take-it-or-leave-it survey valuation question is more likely to reflect real daily world market decisions which individuals are confronted with. Moreover, the dichotomous choice referendum reveals itself to be less vulnerable to strategic bidding behaviour than, for example, the open ended elicitation format; <br />
# CVM should contain an accurate and understandable description of the program or policy under consideration and the associated environmental benefits in each of the two scenarios, i.e., with and without the policy. Interdisciplinary work with other research areas, namely the biological sciences, is recommended;<br />
# CVM should include reminders of the substitutes for the commodity in question as well as its budget. In a context where the respondents are being asked how they would vote on a financial contribution to protect a natural area, the respondents should be reminded of the existence of the other areas that exist. Moreover the respondent should be reminded that such contribution would reduce the amount of money that he or she has available to spend on other things. The major idea here is to make such a (hypothetical) valuation exercise resemble as closely as possible an actual market transaction;<br />
# CVM experiments should include a follow-up section at the end of the questionnaire to be sure if the respondents understood (or not) the choice that they were asked to make.<br />
<br />
==References==<br />
<references/><br />
<br />
==Further reading==<br />
:Carson, R. T., R. C. Mitchell, W. M. Hanemann, R. J. Kopp, S. Presser and P. A. Ruud (1992) “A Contingent Valuation Study of Lost Passive Use Values Resulting from the Exxon Valdez Oil Spill”, Report prepared for the Attorney General of the State of Alaska, Washington. (Carson et al. 1992)<br />
:Loureiro, M. L., J.B. Loomis and M.X. Vázquez (2007) “[http://www.encora.eu/coastalwiki/Impacts_from_maritime_transport Estimating the Non-Market Environmental Damages caused by the Prestige Oil Spill]”, IDEGA-Universidade de Santiago de Compostela, working paper.<br />
:Mitchell, R. C. and R. T. Carson (1989) “Using Surveys to Value Public Goods. The Contingent Valuation Method]”, Washington DC, Resources for the Future. <br />
:Nunes, P.A.L.D. and A. de Blaeij (2005) “Economic Assessment of Marine Quality Benefits: Applying the Use of Non-Market Valuation Methods”, in Maes, Frank (Ed.), Marine Resource Damage Assessment, Liability and Compensation for Environmental Damage, Chapter 7, Springer Publishers, Amsterdam, The Netherlands. <br />
:Nunes, P.A.L.D. and J.C.J.M. van den Bergh (2004) “Valuing non-market benefits for protection against exotic marine species in the Netherlands using TC and CV data”, Environment and Resource Economics, 28, pp. 517-532.<br />
:Nunes, P.A.L.D. and P. Nijkamp (2007) “Contingent Valuation Method” in M. Deakin, G. Mitchell, P. Nijkamp and R. Vreeker (Eds.), Sustainable Urban Development (Volume 2): The Environmental Assessment Methods, Chapter 8, Routledge, UK. <br />
:Nunes, P.A.L.D. (2002) “The Contingent Valuation of Natural Parks: Assessing the Warmglow Propensity Factor” Edward Elgar Publishing (UK), New Horizons in Environmental Economics Series. <br />
:Nunes, P.A.L.D. and E. Schokkaert (2003) “Identifying the warm glow effect in contingent valuation”, Journal of Environmental Economics and Management, vol. 45, 231-245.<br />
<br />
{{author<br />
|AuthorID=11621<br />
|AuthorFullName=Paulo A. L. D. Nunes<br />
|AuthorName=Pnunes}}<br />
<br />
[[Category:Theme_1]]<br />
[[Category:Coastal management]]<br />
[[Category:Evaluation and assessment in coastal management]]<br />
[[Category:Techniques and methods in coastal management]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Contingent_Valuation_Method&diff=27534
Contingent Valuation Method
2009-02-27T15:06:15Z
<p>Wouter Kreiken: /* The Reagan Executive Order */</p>
<hr />
<div>{{Links}}<br />
<br />
The '''Contingent Valuation Method''' (CVM) is an economic, non-market based valuation method especially used to infer individual’s preferences for public goods, notably environmental quality. For this same reason, CVM is known in the literature by exploring the use of questionnaires and asking directly consumers, i.e. respondents, for their maximum willingness to pay (WTP) for specified improvements in the environmental quality, including protection of marine [[biodiversity]]. In short, CVM circumvents the absence of markets for public goods by presenting consumers with a survey market in which they have the opportunity to buy the good in question – protection of marine [[biodiversity]]. Because the elicited WTP values are contingent upon the market described to the respondents, this approach came to be called the contingent valuation method. <br />
<br />
==Introduction==<br />
The survey market should be modelled after a political market, notably in a referendum format. In other words, respondents should be asked how they would vote (favour or against) upon a described marine environmental protection program, taking into account that its approval would imply the payment of a tax. For each if the protection program refers to the introduction of a [[ballast water]] treatment complex in European harbours one could model the WTP question as follows: “''If the total tax amount to be paid for the water treatment complex was 30 Euro per year for the next 2 years, and thus keeping European coast free from exotic [[algae]] and the beaches free from [[algae foams]], how would you vote on the introduction this tax?''” Bearing in mind the answer of the respondents to this question and the use of appropriated econometric tools, economists are able assess the individual demand for environmental quality and thus quantify in monetary terms the underlying welfare changes. The typical CVM survey consists of three sections. <br />
<br />
The first section is '''characterized by the description of the environmental change''' as conveyed by the policy formulation and the description of the contingent market. The policy formulation involves describing the availability (or quality) of the environmental commodity in both the ‘reference state’ (usually the status quo) and ‘target state’ (usually depicting the policy action). Since all monetary transactions occur in a social context, it is also crucial to define the contingent market - most of the time rather unfamiliar to the respondents - by stating to the respondent both the rules specifying the conditions that would lead to policy implementation as well the payment to be exacted from the respondent’s household in the event of policy implementation. <br />
<br />
The second section is where the '''respondent is asked to state her monetary valuation for the described policy formulation'''. This part is the core of the questionnaire. The major objective of this section is to obtain a monetary measure of the maximum Willingness to Pay that the individual consumers are willing to pay for the described environmental policy action. <br />
<br />
The third section of the CVM instrument is a set of '''questions that collect socio-demographic information about the respondents'''. The answers to these questions help to better characterise the respondent’s profile and are used to understand the respondent’s stated WTP responses. The third section finishes with follow-up questions. The follow-up questions are answered by the interviewers. The goal is to assess whether the respondents have (well) understood the CVM survey in general, and the valuation question in particular see [[#A brief history of contingent valuation|A brief history of contingent valuation]] for more details on the practice of this method.<br />
<br />
Today, the CVM is one of the most used techniques for valuation of environmental benefits, widely used by academic institutions as well as by governmental agencies as a crucial tool in cost-benefit analysis and damage cost assessment [[#The National Oceanic Atmospheric Administration Panel|(see NOAA Panel for more technical details on how to construct an efficient survey)]]. This is partly due to the advantages of CVM compared to other valuation methods. First, the CVM method gives immediately a monetary assessment of respondents’ preferences. Second, the CVM method is the only valuation technique that is capable of shedding light on the monetary valuation of the non-use values, i.e., the benefit value component of the environmental commodity that is not directly associated with its direct use or consumption. These values are characterized by having no behavioural market trace. Therefore, economists cannot glean information about these values relying on market-based valuation approaches. For environmental resources such as the protection of [[natural parks]] or [[biodiversity]] sensitive areas, which play an important role in guaranteeing the protection of local wildlife diversity, the non-use value component may account for the major part of the conservation benefits. Ignoring such values will be responsible for a systematic bias in the estimation (an underestimation) of the total economic value of the related environment. Third, CVM brings with it the advantage that environmental quality changes may be valued even if they have not yet occurred (ex ante valuation). This implies that the CVM can be a useful advisory tool for policy decision-making. Furthermore, the constructed nature of the CVM method permits to value environmental changes even if they have not yet occurred. Therefore, CVM offers a greater potential scope and flexibility than the revealed preference methods since it is possible to specify different states of nature (policy scenarios) that may even lie outside the current institutional arrangements or levels of provision.<br />
<br />
==A brief history of contingent valuation==<br />
The first CVM published reference dates from 1947. We refer to the Ciriacy-Wantrup<ref>Ciriacy-Wantrup (1947) “Capital Returns from Soil Conservation Practices”, Journal of Farms Economics, 29, 1180-1190.</ref> article published in the Journal of Farms Economics. The study focuses on the valuation of the economic effects of preventing soil [[erosion]]. The author suggested that one way to obtain information on the demand for these favourable effects would be to ask directly the individuals how much they would be willing to pay for successive increments. However, no empirical valuation was attempted. However, the first CVM design and implementation only occurred two decades later when Robert Davis assessed the economic value of the recreational possibilities of the Maine Woods by exploring the survey technique (Davis 1963<ref>DAVIS, Robert K. (1963)"The Value of Outdoor Recreation: An Economic Study of the Maine Woods" Ph.D. dissertation. Harvard University</ref>). Davis simulated a market behaviour situation by putting the interviewer in the “''position of a seller who elicits the highest possible bid from the users of the services being offered''”. <br />
<br />
Since these early beginnings, the CVM has been used to measure benefits of a wide range of environmental goods including recreation, amenity value, scenery, forests, [[wetlands]], wildlife, air and water quality. More recently, there has been a trend to conduct CVM studies not only to value environmental goods, but also to investigate the various methodological issues involved in the valuation exercise, including the study of the impact of consumer’s attitudes, motivations on CVM estimates. Furthermore, throughout these decades, the CVM has gone through several phases, emerging from the academy into the rough and tumble of the outside world. Strong development stimulus was given by the [http://en.wikisource.org/wiki/Executive_Order_12291 Reagan Executive Order 12291], introduced in 1981; the re-interpretation of CERCLA, in 1989; the Exxon Valdez damage assessment, in 1992, and, more recently, the NOAA panel<ref>NOAA – National Oceanic and Atmospheric Administration (1993) “Report of the NOAA Panel on Contingent Valuation”, Federal Register, Vol 58, no. 10, US, 4601-4614.</ref>.<br />
<br />
===The Reagan Executive Order ===<br />
The [http://en.wikisource.org/wiki/Executive_Order_12291 Reagan Executive Order 12291], introduced in 1981, constitutes a strong stimulus for the development of the monetary valuation methods of environmental commodities. In concrete terms, the Executive Order stipulated that all federal regulations on environmental policy should be submitted to a cost-benefit analysis. All regulations, including both the promulgation of new regulations and the review of the existing ones, would only be carried out if a positive present value for the society could be achieved. Therefore, the social benefits had to be monetized. The flexibility and generality of CVM’s application was the main reason why this valuation method received most of the [http://www.epa.gov/ EPA]’s “demands” in the monetary assessment of the social costs and benefits associated with the new regulations on environmental policy. Thus, the appearance of Executive Order 12291 had a major impact in the development of the CVM. Furthermore, the District of Columbia Court of Appeals re-interpretation in 1989 of the [http://www.epa.gov/superfund/policy/cercla.htm US Comprehensive Environmental Response, Compensation and Liability Act] of 1980 (USDI 1989) expressed not only the legitimacy of non-use values as a component of the total resource value, but also granted equal standing to stated and revealed preferences evaluation techniques. Such a governmental decision was responsible for the expansion of the CVM beyond the academic world, now fully recognized as a fair, conventional method to shed light on the economic value of environmental quality, corner stone of an efficient, well accepted policy design.<br />
<br />
===Exxon Valdez oil spill===<br />
Another important benchmark in the history of the CVM is the massive [[oil spills|oil spill]] due to the grounding of the oil tanker [[http://www.encora.eu/coastalwiki/North_Sea_pollution_from_shipping:_legal_framework#Accidental_pollution|Exxon Valdez]] in the Prince William Sound in the Northern part of the Gulf of Alaska on March 24, 1989. This [[oil spills|oil spill]] was the largest [[oil spills|oil spill]] from a tanker in US history: more than 1,300 kilometres of coastline were affected and almost 23,000 birds were killed. After the [[oil spills|oil spill]], the State of Alaska commissioned various studies to identify the physical damage to the natural resources. The follow-up economic damage assessment studies also take into account, in addition to water purification costs, economic losses such as the decrease in revenue from recreation and fisheries. Moreover, the State of Alaska appointed an interdisciplinary group of researchers to design and implement a national CVM study to measure the loss of non - use values to US citizens as a result of the [[oil spills|oil spill]]. This study was coordinated by Richard Carson and constitutes one of the major contingent valuation applications and represents an important methodological reference for all contingent valuation researchers' work. The loss of non - use values resulting from the Exxon Valdez oil spill was estimated at 2,8 billion dollars. <br />
<br />
However, and anticipating these high financial consequences, Exxon commissioned a group of researchers to verify whether non - use values could be accurately measured by means of CVM. The main argument of critics of CVM is that this method is not capable of resulting in valid and reliable monetary measures of non-use values. Hausman’s well-know argument “is some number better than no number”<ref>Diamon, P.A.; Hausman, J.A. (1994) Contingent Valuation: Is Some Number better than No Number? The Journal of Economic Perspectives, Vol. 8, No. 4. (Autumn, 1994), pp. 45-64.</ref> fully expresses the scepticism toward the CVM method. Therefore, according to Hausman, assessments of lost non-use values by means of the CVM method should not be used in court. In order to address Hausman’s critique, the National Oceanic and Atmospheric Administration set a group of experts in order to evaluate the reliability of the use of CVM in the natural resource damage assessments.<br />
<br />
==The National Oceanic and Atmospheric Administration Panel==<br />
A panel of experts, with the Nobel Laureates Kenneth Arrow and Robert Solow as chairmen, provided advice to the [http://www.noaa.gov/ National Oceanic and Atmospheric Administration], (NOAA) on the following question: “is the contingent valuation method capable of providing estimates of lost non - use or existence values that are reliable enough to be used in the natural resource damage assessments?” The final advice of the NOAA panel may be summarised by the following sentence:<br />
<br />
:"''... the Panel concludes that well conducted CVM studies can produce estimates reliable enough to be the starting point of a judicial process of damage assessment, including lost passive values.''" <ref>NOAA, Federal Register, Vol. 58, No. 10, page 4610</ref> <br />
This conclusion cheered all researchers who wish to use the contingent valuation. However, the Panel was rather prudent with its conclusion and qualified such a statement by establishing a set of guidelines, recommended to all future CVM applications, concerning the design and execution of the survey instrument. The six most important guidelines, also well known as the six pillars of the NOAA, are summarised as follows:<br />
# CVM should rely on face-to-face interviews rather than telephone interviews, and whenever this is not possible (specially because of the high costs associated with the personal interviews) telephone interviews are preferable to mail surveys;<br />
# CVM should elicit the respondent’s WTP to prevent a future incident rather than WTA (Willingness to Accept) for an incident already occurred;<br />
# CVM should use a dichotomous choice referendum elicitation format, i.e., the respondents should be asked how they would vote (favour or against) upon a described environmental quality change. The main reason for the dichotomous choice is that such a take-it-or-leave-it survey valuation question is more likely to reflect real daily world market decisions which individuals are confronted with. Moreover, the dichotomous choice referendum reveals itself to be less vulnerable to strategic bidding behaviour than, for example, the open ended elicitation format; <br />
# CVM should contain an accurate and understandable description of the program or policy under consideration and the associated environmental benefits in each of the two scenarios, i.e., with and without the policy. Interdisciplinary work with other research areas, namely the biological sciences, is recommended;<br />
# CVM should include reminders of the substitutes for the commodity in question as well as its budget. In a context where the respondents are being asked how they would vote on a financial contribution to protect a natural area, the respondents should be reminded of the existence of the other areas that exist. Moreover the respondent should be reminded that such contribution would reduce the amount of money that he or she has available to spend on other things. The major idea here is to make such a (hypothetical) valuation exercise resemble as closely as possible an actual market transaction;<br />
# CVM experiments should include a follow-up section at the end of the questionnaire to be sure if the respondents understood (or not) the choice that they were asked to make.<br />
<br />
==References==<br />
<references/><br />
<br />
==Further reading==<br />
:Carson, R. T., R. C. Mitchell, W. M. Hanemann, R. J. Kopp, S. Presser and P. A. Ruud (1992) “A Contingent Valuation Study of Lost Passive Use Values Resulting from the Exxon Valdez Oil Spill”, Report prepared for the Attorney General of the State of Alaska, Washington. (Carson et al. 1992)<br />
:Loureiro, M. L., J.B. Loomis and M.X. Vázquez (2007) “[http://www.encora.eu/coastalwiki/Impacts_from_maritime_transport Estimating the Non-Market Environmental Damages caused by the Prestige Oil Spill]”, IDEGA-Universidade de Santiago de Compostela, working paper.<br />
:Mitchell, R. C. and R. T. Carson (1989) “Using Surveys to Value Public Goods. The Contingent Valuation Method]”, Washington DC, Resources for the Future. <br />
:Nunes, P.A.L.D. and A. de Blaeij (2005) “Economic Assessment of Marine Quality Benefits: Applying the Use of Non-Market Valuation Methods”, in Maes, Frank (Ed.), Marine Resource Damage Assessment, Liability and Compensation for Environmental Damage, Chapter 7, Springer Publishers, Amsterdam, The Netherlands. <br />
:Nunes, P.A.L.D. and J.C.J.M. van den Bergh (2004) “Valuing non-market benefits for protection against exotic marine species in the Netherlands using TC and CV data”, Environment and Resource Economics, 28, pp. 517-532.<br />
:Nunes, P.A.L.D. and P. Nijkamp (2007) “Contingent Valuation Method” in M. Deakin, G. Mitchell, P. Nijkamp and R. Vreeker (Eds.), Sustainable Urban Development (Volume 2): The Environmental Assessment Methods, Chapter 8, Routledge, UK. <br />
:Nunes, P.A.L.D. (2002) “The Contingent Valuation of Natural Parks: Assessing the Warmglow Propensity Factor” Edward Elgar Publishing (UK), New Horizons in Environmental Economics Series. <br />
:Nunes, P.A.L.D. and E. Schokkaert (2003) “Identifying the warm glow effect in contingent valuation”, Journal of Environmental Economics and Management, vol. 45, 231-245.<br />
<br />
{{author<br />
|AuthorID=11621<br />
|AuthorFullName=Paulo A. L. D. Nunes<br />
|AuthorName=Pnunes}}<br />
<br />
[[Category:Theme_1]]<br />
[[Category:Coastal management]]<br />
[[Category:Evaluation and assessment in coastal management]]<br />
[[Category:Techniques and methods in coastal management]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Contingent_Valuation_Method&diff=27533
Contingent Valuation Method
2009-02-27T15:04:54Z
<p>Wouter Kreiken: </p>
<hr />
<div>{{Links}}<br />
<br />
The '''Contingent Valuation Method''' (CVM) is an economic, non-market based valuation method especially used to infer individual’s preferences for public goods, notably environmental quality. For this same reason, CVM is known in the literature by exploring the use of questionnaires and asking directly consumers, i.e. respondents, for their maximum willingness to pay (WTP) for specified improvements in the environmental quality, including protection of marine [[biodiversity]]. In short, CVM circumvents the absence of markets for public goods by presenting consumers with a survey market in which they have the opportunity to buy the good in question – protection of marine [[biodiversity]]. Because the elicited WTP values are contingent upon the market described to the respondents, this approach came to be called the contingent valuation method. <br />
<br />
==Introduction==<br />
The survey market should be modelled after a political market, notably in a referendum format. In other words, respondents should be asked how they would vote (favour or against) upon a described marine environmental protection program, taking into account that its approval would imply the payment of a tax. For each if the protection program refers to the introduction of a [[ballast water]] treatment complex in European harbours one could model the WTP question as follows: “''If the total tax amount to be paid for the water treatment complex was 30 Euro per year for the next 2 years, and thus keeping European coast free from exotic [[algae]] and the beaches free from [[algae foams]], how would you vote on the introduction this tax?''” Bearing in mind the answer of the respondents to this question and the use of appropriated econometric tools, economists are able assess the individual demand for environmental quality and thus quantify in monetary terms the underlying welfare changes. The typical CVM survey consists of three sections. <br />
<br />
The first section is '''characterized by the description of the environmental change''' as conveyed by the policy formulation and the description of the contingent market. The policy formulation involves describing the availability (or quality) of the environmental commodity in both the ‘reference state’ (usually the status quo) and ‘target state’ (usually depicting the policy action). Since all monetary transactions occur in a social context, it is also crucial to define the contingent market - most of the time rather unfamiliar to the respondents - by stating to the respondent both the rules specifying the conditions that would lead to policy implementation as well the payment to be exacted from the respondent’s household in the event of policy implementation. <br />
<br />
The second section is where the '''respondent is asked to state her monetary valuation for the described policy formulation'''. This part is the core of the questionnaire. The major objective of this section is to obtain a monetary measure of the maximum Willingness to Pay that the individual consumers are willing to pay for the described environmental policy action. <br />
<br />
The third section of the CVM instrument is a set of '''questions that collect socio-demographic information about the respondents'''. The answers to these questions help to better characterise the respondent’s profile and are used to understand the respondent’s stated WTP responses. The third section finishes with follow-up questions. The follow-up questions are answered by the interviewers. The goal is to assess whether the respondents have (well) understood the CVM survey in general, and the valuation question in particular see [[#A brief history of contingent valuation|A brief history of contingent valuation]] for more details on the practice of this method.<br />
<br />
Today, the CVM is one of the most used techniques for valuation of environmental benefits, widely used by academic institutions as well as by governmental agencies as a crucial tool in cost-benefit analysis and damage cost assessment [[#The National Oceanic Atmospheric Administration Panel|(see NOAA Panel for more technical details on how to construct an efficient survey)]]. This is partly due to the advantages of CVM compared to other valuation methods. First, the CVM method gives immediately a monetary assessment of respondents’ preferences. Second, the CVM method is the only valuation technique that is capable of shedding light on the monetary valuation of the non-use values, i.e., the benefit value component of the environmental commodity that is not directly associated with its direct use or consumption. These values are characterized by having no behavioural market trace. Therefore, economists cannot glean information about these values relying on market-based valuation approaches. For environmental resources such as the protection of [[natural parks]] or [[biodiversity]] sensitive areas, which play an important role in guaranteeing the protection of local wildlife diversity, the non-use value component may account for the major part of the conservation benefits. Ignoring such values will be responsible for a systematic bias in the estimation (an underestimation) of the total economic value of the related environment. Third, CVM brings with it the advantage that environmental quality changes may be valued even if they have not yet occurred (ex ante valuation). This implies that the CVM can be a useful advisory tool for policy decision-making. Furthermore, the constructed nature of the CVM method permits to value environmental changes even if they have not yet occurred. Therefore, CVM offers a greater potential scope and flexibility than the revealed preference methods since it is possible to specify different states of nature (policy scenarios) that may even lie outside the current institutional arrangements or levels of provision.<br />
<br />
==A brief history of contingent valuation==<br />
The first CVM published reference dates from 1947. We refer to the Ciriacy-Wantrup<ref>Ciriacy-Wantrup (1947) “Capital Returns from Soil Conservation Practices”, Journal of Farms Economics, 29, 1180-1190.</ref> article published in the Journal of Farms Economics. The study focuses on the valuation of the economic effects of preventing soil [[erosion]]. The author suggested that one way to obtain information on the demand for these favourable effects would be to ask directly the individuals how much they would be willing to pay for successive increments. However, no empirical valuation was attempted. However, the first CVM design and implementation only occurred two decades later when Robert Davis assessed the economic value of the recreational possibilities of the Maine Woods by exploring the survey technique (Davis 1963<ref>DAVIS, Robert K. (1963)"The Value of Outdoor Recreation: An Economic Study of the Maine Woods" Ph.D. dissertation. Harvard University</ref>). Davis simulated a market behaviour situation by putting the interviewer in the “''position of a seller who elicits the highest possible bid from the users of the services being offered''”. <br />
<br />
Since these early beginnings, the CVM has been used to measure benefits of a wide range of environmental goods including recreation, amenity value, scenery, forests, [[wetlands]], wildlife, air and water quality. More recently, there has been a trend to conduct CVM studies not only to value environmental goods, but also to investigate the various methodological issues involved in the valuation exercise, including the study of the impact of consumer’s attitudes, motivations on CVM estimates. Furthermore, throughout these decades, the CVM has gone through several phases, emerging from the academy into the rough and tumble of the outside world. Strong development stimulus was given by the [http://en.wikisource.org/wiki/Executive_Order_12291 Reagan Executive Order 12291], introduced in 1981; the re-interpretation of CERCLA, in 1989; the Exxon Valdez damage assessment, in 1992, and, more recently, the NOAA panel<ref>NOAA – National Oceanic and Atmospheric Administration (1993) “Report of the NOAA Panel on Contingent Valuation”, Federal Register, Vol 58, no. 10, US, 4601-4614.</ref>.<br />
<br />
===The Reagan Executive Order ===<br />
The [http://en.wikisource.org/wiki/Executive_Order_12291 Reagan Executive Order 12291], introduced in 1981, constitutes a strong stimulus for the development of the monetary valuation methods of environmental commodities. In concrete terms, the Executive Order stipulated that all federal regulations on environmental policy should be submitted to a cost-benefit analysis. All regulations, including both the promulgation of new regulations and the review of the existing ones, would only be carried out if a positive present value for the society could be achieved. Therefore, the social benefits had to be monetized. The flexibility and generality of CVM’s application was the main reason why this valuation method received most of the [[EPA]]’s “demands” in the monetary assessment of the social costs and benefits associated with the new regulations on environmental policy. Thus, the appearance of Executive Order 12291 had a major impact in the development of the CVM. Furthermore, the District of Columbia Court of Appeals re-interpretation in 1989 of the [http://www.epa.gov/superfund/policy/cercla.htm US Comprehensive Environmental Response, Compensation and Liability Act] of 1980 (USDI 1989) expressed not only the legitimacy of non-use values as a component of the total resource value, but also granted equal standing to stated and revealed preferences evaluation techniques. Such a governmental decision was responsible for the expansion of the CVM beyond the academic world, now fully recognized as a fair, conventional method to shed light on the economic value of environmental quality, corner stone of an efficient, well accepted policy design.<br />
<br />
===Exxon Valdez oil spill===<br />
Another important benchmark in the history of the CVM is the massive [[oil spills|oil spill]] due to the grounding of the oil tanker [[http://www.encora.eu/coastalwiki/North_Sea_pollution_from_shipping:_legal_framework#Accidental_pollution|Exxon Valdez]] in the Prince William Sound in the Northern part of the Gulf of Alaska on March 24, 1989. This [[oil spills|oil spill]] was the largest [[oil spills|oil spill]] from a tanker in US history: more than 1,300 kilometres of coastline were affected and almost 23,000 birds were killed. After the [[oil spills|oil spill]], the State of Alaska commissioned various studies to identify the physical damage to the natural resources. The follow-up economic damage assessment studies also take into account, in addition to water purification costs, economic losses such as the decrease in revenue from recreation and fisheries. Moreover, the State of Alaska appointed an interdisciplinary group of researchers to design and implement a national CVM study to measure the loss of non - use values to US citizens as a result of the [[oil spills|oil spill]]. This study was coordinated by Richard Carson and constitutes one of the major contingent valuation applications and represents an important methodological reference for all contingent valuation researchers' work. The loss of non - use values resulting from the Exxon Valdez oil spill was estimated at 2,8 billion dollars. <br />
<br />
However, and anticipating these high financial consequences, Exxon commissioned a group of researchers to verify whether non - use values could be accurately measured by means of CVM. The main argument of critics of CVM is that this method is not capable of resulting in valid and reliable monetary measures of non-use values. Hausman’s well-know argument “is some number better than no number”<ref>Diamon, P.A.; Hausman, J.A. (1994) Contingent Valuation: Is Some Number better than No Number? The Journal of Economic Perspectives, Vol. 8, No. 4. (Autumn, 1994), pp. 45-64.</ref> fully expresses the scepticism toward the CVM method. Therefore, according to Hausman, assessments of lost non-use values by means of the CVM method should not be used in court. In order to address Hausman’s critique, the National Oceanic and Atmospheric Administration set a group of experts in order to evaluate the reliability of the use of CVM in the natural resource damage assessments.<br />
<br />
==The National Oceanic and Atmospheric Administration Panel==<br />
A panel of experts, with the Nobel Laureates Kenneth Arrow and Robert Solow as chairmen, provided advice to the [http://www.noaa.gov/ National Oceanic and Atmospheric Administration], (NOAA) on the following question: “is the contingent valuation method capable of providing estimates of lost non - use or existence values that are reliable enough to be used in the natural resource damage assessments?” The final advice of the NOAA panel may be summarised by the following sentence:<br />
<br />
:"''... the Panel concludes that well conducted CVM studies can produce estimates reliable enough to be the starting point of a judicial process of damage assessment, including lost passive values.''" <ref>NOAA, Federal Register, Vol. 58, No. 10, page 4610</ref> <br />
This conclusion cheered all researchers who wish to use the contingent valuation. However, the Panel was rather prudent with its conclusion and qualified such a statement by establishing a set of guidelines, recommended to all future CVM applications, concerning the design and execution of the survey instrument. The six most important guidelines, also well known as the six pillars of the NOAA, are summarised as follows:<br />
# CVM should rely on face-to-face interviews rather than telephone interviews, and whenever this is not possible (specially because of the high costs associated with the personal interviews) telephone interviews are preferable to mail surveys;<br />
# CVM should elicit the respondent’s WTP to prevent a future incident rather than WTA (Willingness to Accept) for an incident already occurred;<br />
# CVM should use a dichotomous choice referendum elicitation format, i.e., the respondents should be asked how they would vote (favour or against) upon a described environmental quality change. The main reason for the dichotomous choice is that such a take-it-or-leave-it survey valuation question is more likely to reflect real daily world market decisions which individuals are confronted with. Moreover, the dichotomous choice referendum reveals itself to be less vulnerable to strategic bidding behaviour than, for example, the open ended elicitation format; <br />
# CVM should contain an accurate and understandable description of the program or policy under consideration and the associated environmental benefits in each of the two scenarios, i.e., with and without the policy. Interdisciplinary work with other research areas, namely the biological sciences, is recommended;<br />
# CVM should include reminders of the substitutes for the commodity in question as well as its budget. In a context where the respondents are being asked how they would vote on a financial contribution to protect a natural area, the respondents should be reminded of the existence of the other areas that exist. Moreover the respondent should be reminded that such contribution would reduce the amount of money that he or she has available to spend on other things. The major idea here is to make such a (hypothetical) valuation exercise resemble as closely as possible an actual market transaction;<br />
# CVM experiments should include a follow-up section at the end of the questionnaire to be sure if the respondents understood (or not) the choice that they were asked to make.<br />
<br />
==References==<br />
<references/><br />
<br />
==Further reading==<br />
:Carson, R. T., R. C. Mitchell, W. M. Hanemann, R. J. Kopp, S. Presser and P. A. Ruud (1992) “A Contingent Valuation Study of Lost Passive Use Values Resulting from the Exxon Valdez Oil Spill”, Report prepared for the Attorney General of the State of Alaska, Washington. (Carson et al. 1992)<br />
:Loureiro, M. L., J.B. Loomis and M.X. Vázquez (2007) “[http://www.encora.eu/coastalwiki/Impacts_from_maritime_transport Estimating the Non-Market Environmental Damages caused by the Prestige Oil Spill]”, IDEGA-Universidade de Santiago de Compostela, working paper.<br />
:Mitchell, R. C. and R. T. Carson (1989) “Using Surveys to Value Public Goods. The Contingent Valuation Method]”, Washington DC, Resources for the Future. <br />
:Nunes, P.A.L.D. and A. de Blaeij (2005) “Economic Assessment of Marine Quality Benefits: Applying the Use of Non-Market Valuation Methods”, in Maes, Frank (Ed.), Marine Resource Damage Assessment, Liability and Compensation for Environmental Damage, Chapter 7, Springer Publishers, Amsterdam, The Netherlands. <br />
:Nunes, P.A.L.D. and J.C.J.M. van den Bergh (2004) “Valuing non-market benefits for protection against exotic marine species in the Netherlands using TC and CV data”, Environment and Resource Economics, 28, pp. 517-532.<br />
:Nunes, P.A.L.D. and P. Nijkamp (2007) “Contingent Valuation Method” in M. Deakin, G. Mitchell, P. Nijkamp and R. Vreeker (Eds.), Sustainable Urban Development (Volume 2): The Environmental Assessment Methods, Chapter 8, Routledge, UK. <br />
:Nunes, P.A.L.D. (2002) “The Contingent Valuation of Natural Parks: Assessing the Warmglow Propensity Factor” Edward Elgar Publishing (UK), New Horizons in Environmental Economics Series. <br />
:Nunes, P.A.L.D. and E. Schokkaert (2003) “Identifying the warm glow effect in contingent valuation”, Journal of Environmental Economics and Management, vol. 45, 231-245.<br />
<br />
{{author<br />
|AuthorID=11621<br />
|AuthorFullName=Paulo A. L. D. Nunes<br />
|AuthorName=Pnunes}}<br />
<br />
[[Category:Theme_1]]<br />
[[Category:Coastal management]]<br />
[[Category:Evaluation and assessment in coastal management]]<br />
[[Category:Techniques and methods in coastal management]]</div>
Wouter Kreiken
https://www.marinespecies.org/r/index.php?title=Thermohaline_circulation_of_the_oceans&diff=27532
Thermohaline circulation of the oceans
2009-02-27T14:55:27Z
<p>Wouter Kreiken: removed internal links lacking tag</p>
<hr />
<div>==Introduction==<br />
<br />
The Thermohaline Circulation (THC) also referred to as the “Great Ocean Conveyor” or the Meridional Overturning Circulation (MOC), can be defined as the density-impelled circulation of the oceans. Thermohaline is derived from the Greek: thermo- for heat and -haline for salt, which constitute the density of water. The water masses transport both energy (heat) and matter (solids, dissolved substances and gasses) around the globe. Changes in the Thermohaline Circulation alter the global ocean heat transport and affect the global climate.(Broecker, W., 1991<ref>Broecker, W., 1991. The great ocean conveyor. Oceanography 1, 79–89.</ref>)<br />
<br />
==Functioning of the Thermahaline Circulation (THC)==<br />
<br />
The conveyor belt (Fig.1) has its start near Greenland and Iceland in the North Atlantic, where seawater at the surface of the ocean is intensively cooled by means of a wind-driven process called evaporative cooling. Only the pure water molecules are removed during evaporation, resulting in an increase in the salinity of the seawater and therefore an increase in the density of the water mass. Evaporative cooling is predominant in the vicinity of the Norwegian Sea, and the sinking water mass known as the North Atlantic Deep Water (NADW), fills the basin and moves southwards through the crevasses in the submarine sills that connect Greenland, Iceland and Great Britain. From there, it flows very slowly into the deep [[abyssal plain| abyssal plains]] of the Atlantic toward Antarctica where the water mass joins the Antarctic Circumpolar Current. Flow from the Arctic Ocean Basin into the Pacific is blocked by the narrow shallows of the Bering Strait.<br />
<br />
<br />
[[Image:Thermohaline.jpg|thumb|center|400px|Fig.1. The Thermohaline Circulation. Source: IPPC 2001.]]<br />
<br />
<br />
<br />
In the Weddell Sea (Antarctica), the combined effect of evaporative cooling and brine exclusion cause the density of the Antarctic Bottom Water (AABW) to be so high, that it in fact underflows the NADW in the Atlantic Basin. Flow of the AABW into the Pacific is blocked by the Drake Passage between the Antarctic Peninsula and the southernmost tip of South America. Within the Antarctic Circumpolar Current, the AABW and NADW are mixed to create the so-called “Common Water” which flows northward, around Southern Africa where it is split into two routes: one into the Indian Ocean and the other past Australia into the Pacific. In the Indian Ocean, some of the cold and salty water from the Atlantic are refreshed, by means of vertical exchange, with the warmer upper ocean water from the tropical Pacific. Within the Pacific Ocean, the remaining cold water undergoes Haline forcing (net high latitude freshwater gain and low latitude evaporation) and slowly becomes warmer and fresher. The outflow of bottom water makes the sea level of the Atlantic slightly lower than the Pacific. Combined with the difference in salinity, this generates a large flow of warmer upper ocean water from the tropical Pacific to the Indian Ocean through the Indonesian Archipelago to replace the AABW. From there, the water flows up through the South Atlantic towards the tropics. The heated tropical waters of the Atlantic proceed until Greenland, where it once more undergoes evaporative cooling, thereby creating a continuous global thermohaline circulation.<br />
<br />
==Bi-polar characteristic of the Thermahaline Circulation==<br />
<br />
Traditionally, research has been almost exclusively devoted to understanding the sensitivity of the high-latitudinal oceans (especially in the Northern Hemisphere) to freshwater fluxes. These studies have advanced considerably the comprehension of the dynamics and functioning of the North Atlantic Bottom Water (NABW) circulation. In comparison therewith, little is known about the southern sources of deepwater (AABW). It is important to bear in mind that the thermohaline circulation is operated by both deepwater sources, and therefore, the deficit of scientific knowledge limits the complete understanding of decadal to millennial time-scale climate change (Seidov, D., 2000<ref name="seidov">Seidov, D., Barron, E., Haupt, B. J., 2000. Meltwater and the global ocean conveyor: northern versus southern connections. Global and Planetary Change 30, 257-270.</ref>). An example of such a deficit is whether the NADW is the ultimate driver of the conveyor, and if additional variability is generated by freshwater impacts in the Southern Ocean (Seidov, D., 2000<ref name="seidov"/>). A significant influence of the Southern Ocean is supported by several scientific lines of evidence. First, many examples of climate intermittency during the glacial cycles of the Pleistocene remain poorly understood, even though they seem to correlate with major deglaciations(Seidov, D., 2000<ref name="seidov"/>). Second, recent studies (Blunier, T. et al. 1998<ref>, 1998. Asynchrony of Antarctic and Greenland climate change during the last glacial period. Nature 394, 739–743.</ref>, Broecker, W.S., 1994<ref>Broecker, W.S., 1994. Massive iceberg discharges as triggers for global climate change. Nature 372, 421–424.</ref>, Stocker, T.F., 1998 <ref>Stocker, T.F., 1998. The seesaw effect. Science 282, 61–62.</ref>) reveal a bi-polar nature of the glacial cycles of the Pleistocene, e.g. the southern Atlantic leads in the occurrence of several Heinrich Events (Vidal, L. et al., 1999<ref>Vidal, L. et al., 1999. Link between the North and South Atlantic during the [[Heinrich events]] of the last glacial period. Clim. Dyn. 15, 909–919.</ref>). Another study (Birchfield, G.E., Broekcer, W.S., 1990<ref name="birchfield">Birchfield, G.E., Broecker, W.S., 1990. A salt oscillator in the glacial Atlantic? 2. A scale analysis model. Paleoceanography 5, 835–843.</ref>) argues that the Little Ice Age (circa 500 years ago) was caused by far stronger deep ocean ventilation in the Southern Ocean. One reason put forward for enhanced southern ocean ventilation is an increase in Atlantic Ocean salinity. Conversely, a slowdown in ventilation could be caused by reduced surface salinity, associated warming, and sea ice or ice sheet melting in the Southern Ocean after the Little Ice Age(Seidov, D., 2000<ref name="seidov"/>, Broecker, W.S., 2000<ref>Broecker, W.S., 2000. Was a change in thermohaline circulation responsible for the Little Ice Age? Proc. Natl. Acad. Sci. 97 (4), 1339–1342.</ref>). The potential importance of feedbacks between the northern and southern sources of deepwater is still largely unknown.<br />
<br />
==Freshwater sources in the Southern Ocean==<br />
<br />
The source and the character of the freshwater sources in the Southern Hemisphere are different from the Northern Hemisphere. Sea surface salinity (SSS) controls both the Antarctic Bottom Water and Antarctic Intermediate Water northward incursions. The SSS can either be increased due to brine exclusion (during the formation of sea ice) or decreased due to sea ice melting. Sea ice formation and brine exclusion rates therefore play a vital role in the southern circulation regime. Additionally, the Antarctic ice sheet has an important function in governing freshwater fluxes into the Southern Ocean. Concern however has been raised about the stability of the West Antarctic Ice Sheet (WAIS). The Antarctic ice sheet mass balance and its possible contribution to global [[sea level rise]] is a major issue of debate, since the potential for changes in freshwater fluxes or salinity variations to influence the Southern Ocean is clearly evident. It has been indicated (Birchfield, G.E., Broekcer, W.S., 1990<ref name="birchfield"/>) that even a relatively small freshwater influx converted to a low-[[salinity]] signal will hamper the effectiveness of the conveyor operation. These factors have initiated a growing modelling effort designed to investigate the climatic role of the Southern Hemisphere (Seidov, D., 2000<ref name="seidov"/>) .<br />
<br />
==The role of global climate change==<br />
<br />
The ocean, including its abyss, is warming at a rate of 0.5˚C or more per century (Levitus, S., 2000<ref>Levitus, S., Antonov, J.I., Boyer, T.P., Stephens, C., 2000. Warming of the world ocean. Science 287, 2225–2229.</ref>). Although historical observations and paleoclimatic data reveal significant climate variability on decadal to millennial time scales, this ocean warming during the last several decades is linked to global climate change. Changes in the atmospheric abundance of greenhouse gases and aerosols, in solar radiation and land surface properties have altered the energy balance of the climate system. <br />
<br />
The global atmospheric concentration of carbon dioxide has increased from a pre-industrial level of 280 parts per million (ppm) to 379 ppm in 2005(Geo Year Book, 2004/2005<ref name="year">Geo Year Book 2004/2005: An overview of our changing environment. United Nations Environment Program. 80-84.</ref>). This atmospheric concentration of carbon dioxide exceeds by far the natural range over the last 650,000 years (180 to 300 ppm)(Geo Year Book, 2004/2005<ref name="year"/>) as determined from ice cores. Consequently, the change of the global energy balance has seen a decrease in sea ice (Fig. 2) as well as rapid ice sheet and permafrost melting. This excess of high latitudinal freshwater influx can substantially modify the deep ocean circulation. <br />
<br />
[[Image:Melting ice sea.jpg|thumb|center|400px|Fig. 2. Melting sea ice]]<br />
<br />
The sinking that drives the thermohaline circulation depends critically on the water being sufficiently cold and salty. Therefore, any factor that changes the state of the conditions for circulation, can result in a slow-down of the thermohaline circulation, and thereby dramatically influence the climatic state and driving further [[climate change]]. Observations over recent decades suggest that changes in the factors governing circulation are already occurring (Geo Year Book, 2004/2005<ref name="year"/>). This raises concerns about potential abrupt climate changes in the future. Is a complete shutdown of the thermohaline possible?<br />
<br />
===High Latitudinal Freshwater Influx===<br />
In light of the deficit of the scientific understanding of the thermohaline circulation and the feedback potentials between the two deepwater sources, it is difficult to predict the influence of global climate change on the dynamics of the thermohaline. Even within the scientific realm there is disagreement on the possibility of a complete shutdown of the thermohaline circulation. Given this discrepancy, a simulation experiment was conducted (Seidov, D., 2000<ref name="seidov"/>) to analyse the sensitivity of thermohaline circulation to low-salinity perturbations. In this simulation, the authors set out to demonstrate the degree to which the thermohaline circulation is driven by both the NADW and the AABW, by means of a designed series of simplified freshwater influx events, in which all ocean model parameters are held constant except salinity. The results of the experiments were described for: a North Atlantic freshwater influx, a Southern Ocean freshwater influx, and a combined influx for the North Atlantic and Southern Ocean. <br />
<br />
* The North Atlantic Freshwater Influx<br />
The results of the experiment simulating a low-salinity impact (-2 psu than present) on the North-Atlantic conform to what is already known from previous work, namely that the conveyor is weaker and shallower. Temperature differences between the current conditions and this low-salinity scenario indicate cooling in high latitudes of the Atlantic Ocean. This occurs because the reduced NADW production led to a shallow conveyor and cooler and fresher water than today in these latitudes characterises the deep ocean water. In addition to this, the surface ocean has more time to lose heat to the atmosphere because the overturning slowed. The reduced NADW outflow has an evident imprint in the oceanic heat transport. Northward cross-equatorial heat transport is dramatically reduced in the scenario with a strong freshwater impact, which indicates the possibility of a cold episode following a freshwater influx event. If the present-day global warming was potent enough to induce a low-salinity episode in the North Atlantic, caused by iceberg and Arctic sea ice melting, the result could be a tendency towards colder temperature conditions in the Northern Hemisphere. It is important though to note that even with an excessive northern low-salinity signal of -2 psu during the simulation, no complete termination of the conveyor occurred.<br />
<br />
* The Southern Ocean Freshwater Influx<br />
In contrast to the predictable results of the northern low-salinity impact, the results of the Southern Ocean surface freshening are less intuitive. Two aspects are noteworthy: first the circulation changes driven by the low-salinity signal were much stronger, and second, they led to a very strong warming of the deep ocean. Warming takes place over the entire deep ocean and its maximum shifts to the southern edges. This deep-sea warming is caused not only by a substantial increase (by 40-60%) in NADW production, but also because the meridional overturning takes over the entire deep ocean, pushing away the lessened AABW. In the North Atlantic scenario, the freshwater influx impact on the conveyor caused thermal effects only in the deep Atlantic Ocean, whereas in the Southern Ocean, the freshwater scenarios impact is global. The increased NADW outflow in the deep layers leads to increased compensating northward surface water flow. This flow carries more warm and salty subtropical water to convection sites, which might further increase NADW production until the atmosphere warms up to reduce the cooling of the sea surface and subsequently reduce the deep convection. The positive feedback of NADW production and northward heat transport can be viewed as a first link toward high-latitudinal warming in the Northern Hemisphere caused by freshwater influx events in the Southern Ocean.<br />
<br />
* Combined Influx for the North Atlantic and Southern Ocean<br />
The results of a combined low-salinity event of the North Atlantic and the Southern Ocean, display a deepwater regime that is qualitatively similar to a Southern-Ocean-only experiment. Less Deep Ocean warming is observed, however the impact still remains global and substantial. Results of the runs with perturbations to two sources, demonstrates a more powerful response to a freshwater influx event in the Southern Ocean than for those in the North Atlantic. However, much of this power stems from increased NADW production.<br />
<br />
===Sea-Level Change===<br />
[[Sea level rise]] can be caused by either melting of major ice sheets (Fig. 3), or as an indirect effect by freshwater influx events caused by thermal restructuring of the world ocean. As the deep ocean warms up, the sea elevation will change as a result of the thermal expansion of sea water. Historic [http://en.wikipedia.org/wiki/Hydrography hydrographic] data suggest that thermal expansion of the ocean can contribute tens of centimeters to the observed [[sea level rise]] over the last century (Godfrey, J.S., Love, G., 1992<ref>Godfrey, J.S., Love, G., 1992. Assessment of sealevel rise, specific to the South Asian and Australian situations. Seal Level Changes: Determination and Effects. Geophys. Monogr., vol. 69. AGU, Washington, DC, pp. 87–94. </ref>). Some simulations (Church, J.A., Godfrey, J.S., Jacket, D.R., McDougall, T.R., 1991<ref>Church, J.A., Godfrey, J.S., Jacket, D.R., McDougall, T.R., 1991. A model of sealevel rise caused by ocean thermal expansion. J. Clim. 4, 438–456.</ref> indicate that the thermal expansion of the ocean associated with a global warming of 3˚C temperature rise by the year 2050 results in up to 30 cm sea-level rise. In the simulation experiment conducted, (Seidov, D., 2000<ref name="seidov"/>) a significant sea-level rise of approximately 2-3 meter may occur during a Southern Ocean event (Fig. 4). In many sensitive coastal areas the sea-level rise could be over 1 meter. It is important to note that this sea-level rise could occur without significant melting of the ice sheets, including WAIS, which is considered the most vulnerable to climate change(Seidov, D., 2000<ref name="seidov"/>).<br />
<br />
[[Image:Figure_3.jpg|thumb|center|400px|Fig.3. IPCC summary of the observed variations in the cryosphere for the years 1993-2003 <ref>Lemke, P., J. Ren, R.B. Alley, I. Allison, J. Carrasco, G. Flato, Y. Fujii, G. Kaser, P. Mote, R.H. Thomas and T. Zhang, 2007: Observations: Changes in Snow, Ice and Frozen Ground. In: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, US, Pp. 375 </ref>]]<br />
<br />
[[Image:Differences.jpg|thumb|center|400px|Fig. 4: Differences of the sea-level elevations in cm relative to the current situation and a freshwater influx event in the North Atlantic and the Southern Ocean(Seidov, D., 2000<ref name="seidov"/>)]]<br />
<br />
===Indirect Impacts Resulting from Changes in the Thermohaline Circulation===<br />
The changing climatic conditions and the increased freshwater influx in the Polar Regions have seen sea ice retreats from the coastline of Arctic countries by between 150 km and 200 km. According to the [http://www.ipcc.ch/ International Panel on Climate Change] (IPCC), by 2050 the sea ice might retreat up to 800 km as a result of global warming. The loss of ice in the Polar Regions could lead to a sudden acceleration of global warming, as ice reflects radiation or heat from the sun back into space. The absence of sea ice combined with deep ocean warming will see more evaporation and rainfall occurring in these sensitive regions, which in turn will speed up sea ice loss.<br />
<br />
The retreat and loss of sea ice in the Polar Regions will also have a harmful impact on the many species living in the regions. Polar bears, for example, need ice so that they can hunt for seals. A loss of sea ice could make it harder for these animals to acquire enough food. Pregnant females and those with cubs may be particularly at risk. The species of seal that need ice for resting or pup rearing will also be at risk.<br />
<br />
As mentioned above, the change of the thermohaline circulation is expected to alter the speed and patterns of [[ocean currents]], which in turn will impact [[fish stocks]]. According to the [http://www.ipcc.ch/ipccreports/assessments-reports.htm Third Assessment Report] of the [http://www.ipcc.ch/ IPCC]: “Arctic fisheries are among the most productive in the world. Changes in the velocity and direction of ocean currents affect the availability of [[nutrients]] and the disposition of larval and juvenile organisms, thereby influencing recruitment, growth and mortality.” Changes in the fish stocks are already taking place, with the result that some stocks are boosting while others are damaged. For example, Groundfish stocks have shown a positive response to recent climate change, while the thermally sensitive Greenland turbot and King crab stocks in the eastern Bering Sea and Kodiak are declining. The IPCC anticipate that harvests might halve or double depending on the stocks concerned; meanwhile some fisheries might die out altogether while new ones develop. This could increase or decrease local economies by hundreds of millions of dollars annually (IPCC). These projected changes in the [[abundance]] and [[distribution]] of fish stocks and wildlife are just one of the issues facing fishermen, Arctic communities and the indigenous people. <br />
<br />
The Polar Regions annually accumulates pollution, including [[Theme_4_State_of_the_art#Persistent_organic_pollutants|Persistent Organic Pollutants]] (POPs), which have been discharged from industry and agriculture around the globe. Melting of the sea ice could trigger the release of these pollutants which could cause them to re-enter the food chain. This would pose a health threat to top predators, e.g. polar bears and humans in these regions.<br />
<br />
On the other hand, the melting of sea ice could have one economic benefit, namely in the area of shipping. The northwards retreat of sea ice opens up the Northern Sea Route, which would allow vessels to sail from Europe to the Far East by going north of Russia rather than using the existing route, i.e. the Suez Canal. Although this should reduce sailing times, cutting the costs of goods and air pollution, the risk of accidents leading to oil spills still remains.<br />
<br />
==Overview of impacts for coastal regions==<br />
<br />
The major impact for coastal regions caused by a change in the thermohaline circulation will be rising sea levels. There are many coastal sensitive regions around the globe which will be affected by even a small change in the sea level. As indicated above, the changing circulation can rise sea levels by either: melting of sea ice and ice sheets in the Polar Regions or via thermal expansion of the sea water. In 2007 approximately 634 million people lived in coastal areas within 9.1m of the sea level. Two thirds of the world’s cities with more than five million people are located in these low-lying coastal areas. <br />
<br />
The IPCC Working Group II report indicates that current and future climate change would be expected to have a number of impacts, especially on coastal systems. Potential impacts may include: increased [[coastal erosion]], higher [[storm surge]] flooding, inhibition of [[primary production]] processes, more extensive coastal inundation, changes in surface water quality and groundwater characteristics, increased loss of property and coastal habitats, increased [[flood risk]] and potential loss of life, loss of non-monetary cultural resources and values, impacts on agriculture and aquaculture via a decline in soil and water quality, and loss of tourism, recreation and transportation functions. Furthermore the IPCC report concludes that due to the great diversity of coastal environments; regional and local differences in projected relative sea level and climate changes; and differences in the [[resilience]] and [[adaptive capacity]] of [[ecosystems]], sectors and countries, the impacts will be highly variable in time and space and will not necessarily be negative in all situations.<br />
<br />
==See also==<br />
<br />
===Internal Links===<br />
*[[Ocean circulation]]<br />
<br />
===External Links===<br />
* Wikipedia: http://en.wikipedia.org/wiki/Thermohaline_circulation<br />
* Ocean Motion and Surface Currents: http://oceanmotion.org/index.htm<br />
* IPPC: http://www.ipcc.ch/<br />
* UNEP: http://unep.org<br />
* GEO Year Book: http://www.unep.org/geo/yearbook<br />
<br />
==References==<br />
<references/><br />
<br />
<br />
{{author<br />
|AuthorID=16609<br />
|AuthorFullName=Tange, Hannli<br />
|AuthorName=Tange, Hannli}}<br />
[[Category: Theme 5]]<br />
[[Category: Coastal processes, interactions and resources]]<br />
[[Category: Hydrodynamics]]</div>
Wouter Kreiken