An empirical method to estimate bulk particulate refractive index for ocean satellite applications

Abstract

An empirical method is presented here to estimates bulk particulate refractive index using the measured inherent and apparent optical properties from the various waters types of the Arabian Sea. We have used the empirical model, where the bulk refractive index is modeled in terms of the backscattering ratio and the hyperbolic slope of the particle size1. Empirical models are obtained to determine the slope of the particle size and backscattering ratio as a function of the remote sensing reflectance. We have used these algorithms with the IRS-P4 OCM satellite data and derived the refractive index image. The values of indexes are found to be lower for the open ocean and relatively higher for the coastal waters. Distinct features are observed even in the in the waters with similar chlorophyll concentrations. This algorithm provides scope for the classification of water types and detection of blooms.