GOCI’s Atmospheric Correction Technique and its validation

Abstract

Atmospheric correction algorithm is an obligatory process of ocean colour remote sensing. Normally the ocean reflectance quantity is relatively small than the atmospheric reflectance, therefore, an accurate atmospheric correction is a momentous part of ocean colour processing. Most of atmospheric correction method assume that ocean reflectance of near infrared bands are negligible and this method is mainly adopted for the clear water. But for the high turbid water, this blackbody assumption is run out, and including the Yellow Sea, a considerable part of GOCI observation area is under this situation.To separate the ocean signals and atmospheric signals, GOCI Data Processing System (GDPS) mainlyadopts three atmospheric correction method that Spectral Shape Matching Method (SSMM), Sun-Glint Correction Algorithm (SGCA) and KOSC Standard Atmospheric Correction Method.SSMM is first developed in 2004 by Y.H.Ahn and P.Shanmugam and using reference sites where the water leaving radiance’s spectrum shape hardly change.SGCA is developed by HIGEOS and estimates sun-glint, atmospheric parameters and some primary oceanic parameters at once by polynomial fitting. The KOSC Standard Atmospheric Correction method is developed by J.H.Ahn and this method is based on the SeaWiFS standard algorithm. This has been extended aerosol models, near infrared correction for turbid waters and atmospheric transmittanomentous part of ocean colour processing. Most of atmospheric correction method assume that ocean reflectance of near infrared bands are negligible and this method is mainly adopted for the clear water. But for the high turbid water, this blackbody assumption is run out, and including the Yellow Sea, a considerable part of GOCI observation area is under this situation.To separate the ocean signals and atmospheric signals, GOCI Data Processing System (GDPS) mainlyadopts three atmospheric correction method that Spectral Shape Matching Method (S