Difference between revisions of "Template:This weeks featured article"
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| − | == | + | ==Optical measurements in coastal waters== |
| − | + | This article gives an introduction of the instruments available (and the application of these instruments) to measure optical properties in coastal waters. Attention is paid to optical measurements in general, regional characteristics and implications for [[remote sensing]]. | |
| − | + | Optical measuments using satellite and airborne sensors is a powerful, operational tool for monitoring [[coastal zone]]s. This technology can provide accurate, large-scale, synoptic environmental information essential for understanding and managing marine [[ecosystems]]. | |
| + | Optical sensor data allows the assessment of in-water properties, such as suspended matter or [[phytoplankton]] concentration, [[benthic]] substrate type, vegetation composition, and [[bathymetry]]. Optical sampling methods enable for example the continuous and contactless measurement of sediment concentrations, which is an important advantage compared to the mechanical sampling methods. | ||
| + | |||
| + | Optical characteristics of a light-transmitting medium can be specified in terms of its inherent optical properties (IOPs). The main IOPs are: | ||
| + | * the absorption coefficient (a) (m<sup>-1</sup>) | ||
| + | * the scattering coefficient (b) (m<sup>-1</sup>) | ||
| + | * the attenuation coefficient (c), with c = a + b (m<sup>-1</sup>) | ||
| + | * the scattering phase function (β) (sr<sup>-1</sup>) | ||
| + | |||
| + | The total IOPs of a body of seawater can be considered as the sum of the partial contributions from water itself and a number of optically significant constituents. Four classes of constituents can be distinguished: | ||
| + | #[[Phytoplankton]] cells and colonies (Phyt) | ||
| + | #Mineral suspended solids (MSS) | ||
| + | #Coloured dissolved organic matter (CDOM) | ||
| + | #Organic suspended solids or [[detritus]] (OSS) | ||
Revision as of 11:36, 15 December 2008
Optical measurements in coastal waters
This article gives an introduction of the instruments available (and the application of these instruments) to measure optical properties in coastal waters. Attention is paid to optical measurements in general, regional characteristics and implications for remote sensing.
Optical measuments using satellite and airborne sensors is a powerful, operational tool for monitoring coastal zones. This technology can provide accurate, large-scale, synoptic environmental information essential for understanding and managing marine ecosystems. Optical sensor data allows the assessment of in-water properties, such as suspended matter or phytoplankton concentration, benthic substrate type, vegetation composition, and bathymetry. Optical sampling methods enable for example the continuous and contactless measurement of sediment concentrations, which is an important advantage compared to the mechanical sampling methods.
Optical characteristics of a light-transmitting medium can be specified in terms of its inherent optical properties (IOPs). The main IOPs are:
- the absorption coefficient (a) (m-1)
- the scattering coefficient (b) (m-1)
- the attenuation coefficient (c), with c = a + b (m-1)
- the scattering phase function (β) (sr-1)
The total IOPs of a body of seawater can be considered as the sum of the partial contributions from water itself and a number of optically significant constituents. Four classes of constituents can be distinguished:
- Phytoplankton cells and colonies (Phyt)
- Mineral suspended solids (MSS)
- Coloured dissolved organic matter (CDOM)
- Organic suspended solids or detritus (OSS)
