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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Available from: Zhongping Lee, Aug 29, 2015
    • "In semi-analytical algorithms, the estimation of the a(λ) is computed by the sum of absorptions coefficients of phytoplankton, non-algal particles and Colored Detrital Matter. QAA algorithms do not depend on the estimation of others IOPs, they estimate a(λ) directly from R rs and other IOPs are computed from the spectral decomposition of the estimated a(λ) (Lee, Carder, and Arnone 2002). For the b b (λ) estimation, semi-analytical algorithms usually computed it as the sum of the backscattering coefficients for each constituent in water except for CDOM. "
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    ABSTRACT: Bio-optical algorithms have been classify with different terms such as empirical, semi-empirical, semi-analytical, quasi-analytical or analytical algorithms. However, one algorithm has been classified differently in remote sensing literature and a lack of a consistent terminology was found. In this article, description of types of bio-optical algorithm is present as well as a procedure to define the most suitable terminology. This procedure is based on the goal, processes and products of the bio-optical algorithm. The adoption of the proposed classification and terminology for this relatively new area for remote sensing applications is an important step for the development of this growing field.
    Remote Sensing Letters 07/2015; 6(8):613-617. DOI:10.1080/2150704X.2015.1066523 · 1.43 Impact Factor
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    • "In brief , these inland techniques can be roughly categorized into two groups . The first group , semi - analytical bio - optical inversion models , were developed for the coastal ocean ( Lee , Carder , and Arnone 2002 ; Maritorena , Siegel , and Peterson 2002 ) and inland waters ( Shuchman et al . 2013 ; Korosov et al . "
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    International Journal of Remote Sensing 05/2015; 36(7). DOI:10.1080/01431161.2015.1029099 · 1.65 Impact Factor
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    • "The main cause of the difficulty in separating a d (k) and a g (k) is related to the similarity of spectral shapes of these two coefficients, which are typically approximated by the exponential function of light wavelength [e.g., Babin et al., 2003]. As a result, the existing models for partitioning a(k) typically yield the phytoplankton absorption coefficient, a ph (k), and the combined nonphytoplankton absorption coefficient, a dg (k) 5 a d (k) 1 a g (k) [Roesler et al., 1989; Lee et al., 2002; Ciotti and Bricaud, 2006; Zheng and Stramski, 2013a]. There have also been a few attempts to derive separate contributions of a d (k) and a g (k) from partitioning of a(k) [Gallegos and Neale, 2002; Schofield et al., 2004; Lin et al., 2013]. "
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