<title>Accounting for the marine reflectance bidirectionality when processing remotely sensed ocean color data</title>

Abstract

In this study, the bidirectional character of the ocean reflectance has been taken into account in the processing of coastal zone color scanner (CZCS) imagery, taken as an example. This effect is represented by a factor Q, which relates a given upwelling radiance to the upwelling irradiance. In this study, the Q factor has been calculated for many cases, using Monte Carlo simulations and a lookup table for Q has been produced for the wavelengths corresponding to the CZCS channels. The Q((lambda) ) values computed for a chlorophyll concentration of 0.3 mg/m3, are used for a first iteration in the pixel-by-pixel processing method developed for CZCS data. The chlorophyll concentration obtained at the issue of this first loop is used to adjust the Q factor and the chlorophyll concentration is again computed. These iterative calculations are repeated until the convergence in the chlorophyll values is reached. The final results generally show higher values in chlorophyll than those obtained with Q equals 4.5, by 20 - 80%. These tests show that convergence is rapidly obtained and that two iterations suffice to obtain stable values of chlorophyll concentration.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.