Abstract
Comparison of CZCS-derived pigment concentration by standard atmospheric correction
method with sea-truth data in the waters around Japan shows an underestimate by satellite to a
differentdegree. In the range of pigment concentration from 0.2 to 6.0 mg/m3, the CZCSobser
vation is lower than in-situ data from about 50% to a factor of 6. Assuming a constant Angstrom
exponent during atmospheric correction stage has been found to account for this bias, provided
that bio-optical algorithmis valid in those waters. An improved atmospheric correctionmethod
which can estimate the Angstromexponent pixel by pixel has been developed based on Gordon
ocean color radiance model, and has been evaluated by comparison with these in-situ data. The
results demonstrate that this method can increase the accuracy of CZCS-estimated pigment con
centration to the level within the system error (30-40%) of CZCS in-water algorithm.
