Article

Deriving Inherent Optical Properties from Water Color: a Multiband Quasi-Analytical Algorithm for Optically Deep Waters

College of Marine Science, University of South Florida, St. Petersburg 33701, USA.
Applied Optics (Impact Factor: 1.78). 10/2002; 41(27):5755-72. DOI: 10.1364/AO.41.005755
Source: PubMed

ABSTRACT

For open ocean and coastal waters, a multiband quasi-analytical algorithm is developed to retrieve absorption and backscattering coefficients, as well as absorption coefficients of phytoplankton pigments and gelbstoff. This algorithm is based on remote-sensing reflectance models derived from the radiative transfer equation, and values of total absorption and backscattering coefficients are analytically calculated from values of remote-sensing reflectance. In the calculation of total absorption coefficient, no spectral models for pigment and gelbstoff absorption coefficients are used. Actually those absorption coefficients are spectrally decomposed from the derived total absorption coefficient in a separate calculation. The algorithm is easy to understand and simple to implement. It can be applied to data from past and current satellite sensors, as well as to data from hyperspectral sensors. There are only limited empirical relationships involved in the algorithm, and they are for less important properties, which implies that the concept and details of the algorithm could be applied to many data for oceanic observations. The algorithm is applied to simulated data and field data, both non-case1, to test its performance, and the results are quite promising. More independent tests with field-measured data are desired to validate and improve this algorithm.

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    • "The constants result in a change of units from the unitless u to a per unit of solid angle, sr À1 , quantity r rs,l . The above-surface remote-sensing reflectance is given by (Lee et al., 2002): R rs;l ¼ 0:52r rs;l 1 À 1:7r rs;l (16) 2.1.4. Benthic reflectance of macrophytes, benthic microalgae and sediment types In order to calculate the importance of benthic reflectance, the integrated weighting of the water column must be calculated (Sec. "
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