Introduction of atmospheric correction technics for geostationary ocean color imager (GOCI)

Abstract

The received average total radiance of GOCI (Geostationary Ocean Color Imager) will be increased about 40 percent than polar orbit satellite by extended optical path considering geometrical situation of observing target area. Therefore the small error of atmospheric correction is crucial effect in the estimation of water leaving radiance(Lw) in GOCI especially.Korean Ocean Satellite Center (KOSC) developed our own method that is named as Spectrum Shape Matching Method (SSMM) and mainly adopted in the GOCI Data Processing System (GDPS). The basic conception is using in-situ Lw spectrum shape data obtained in the reference sites in the ocean. We could get very stable and more precious values regardless of water’s optical property (case 1 & 2 water) GDPS adopts also another algorithm that named SGCA (Sun-Glint Correction Algorithm) and this technique removes sun-glint and aerosol signals at once. The SGCA is developed by the Lille Univ.and HYGEOS Co. in France and GDPS offers this method instead of SSMM optionally.In this study, we’ll show the results of atmospheric correction by applying SSMM and SCGA methods in GOCI images. And we have studied the possibilities of improved and integrated techniques through the comparison of week and strong points of each method.