Estimation of the inherent optical properties of natural waters from the irradiance attenuation coefficient and reflectance in the presence of Raman scattering

By means of radiative transfer simulations we developed a model for estimat ing the absorption a, the scattering b, and the backscattering b(b) coeffic ients in the upper ocean from irradiance reflectance just beneath the sea s urface, R(0(-)), and the average attenuation coefficient for downwelling ir radiance, (K-d)(1), between the surface and the first attenuation depth. Th e model accounts for Raman scattering by water, and it does not require any assumption about the spectral shapes of a, b, and b(b) The best estimation s are obtained for a and b(b) in the blue and green spectral regions, where errors of a few percent to <10% are expected over a broad range of chlorop hyll concentration in water. The model is useful for satellite ocean color applications because the model input, R(0(-)) and (K-d)(1), can be retrieve d from remote sensing and the model output, a and b(b), is the major determ inant of remote-sensing reflectance. (C) 2000 Optical Society of America. O CIS codes: 010.4450, 030.5620, 280.0280, 290.5860.