Spectral Models for Improving Atmospheric Correction Results in Complex Oceanic Waters around India

Palanisamy Shanmugam, Muniyandi Tholkapiyan

Department of Ocean Engineering, Indian Institute of Technology Madras, Chennai, India.

DOI: 10.4236/ars.2013.22007                

Abstract

Atmospheric correction over turbid and productive waters continues to be problematic and often results in excessive errors in retrieved water-leaving radiance and bio-geo-physical products. This may be likely due to overestimation of L_a + L_ra (atmospheric signal due to aerosol and Rayleigh scattering) in the visible and thus reduction in L_w which appears as an elevated pigment concentration. Spectral models for reconstructing the atmospherically distorted data are developed and their results are thoroughly validated with in-situ data from a wide range of waters. Good agreement was found between the retrieved products and in-situ data. Our results indicate that the new spectral models have the potential to improve the accuracy of ocean colour retrievals in optically complex waters, and can become an important part of the processing of data from ocean colour sensors (e.g., Ocean colour monitor OCM2) with only two near-infrared bands (i.e., 765 and 865 nm).

Keywords

Ocean Colour; Spectral Models; MODIS-Aqua; Algal Blooms; Arabian Sea; India

Conflicts of Interest

The authors declare no conflicts of interest.

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