A study on the satellite-based sea surface salinity mapping in Korean coastal waters

Abstract

Sea surface salinity (SSS) is an important factor in the ocean science, such as estimating oceanic carbon flux, tracing red tide, and calculating other physical processes at the surface. Sea surface salinity can be derived from satellite remote sensing, although little has been successful particularly in the coastal waters. It is well-known that absorption property of colored dissolved organic matter (CDOM) absorption has a strong correlation with SSS in the area that influenced by freshwater inflow. Here, we tested the applicability of CDOM distribution observed from the Geostationary Ocean Colour Imager (GOCI) to mapping SSS in the Korean coastal waters. Empirical relationships between CDOM absorption and SSS are derived from in-situ measurement collected at the Gyeonggi-bay located in the middle of the west coast of Korean peninsula. SSS images derived from GOCI were validated by comparison with the in-situ measurement and were also compared with SSS images provided from HYCOM-modelled, which shows that it is possible to estimate SSS from CDOM absorption at the estuarine environment. Further studies would be needed to improve the algorithm and apply it to other coastal environments around the Korean peninsula. Satellite based SSS from this study can be used for studies on the long-term variations in SSS in this area and its relations with the climate changes.mote sensing, although little has been successful particularly in the coastal waters. It is well-known that absorption property of colored dissolved organic matter (CDOM) absorption has a strong correlation with SSS in the area that influenced by freshwater inflow. Here, we tested the applicability of CDOM distribution observed from the Geostationary Ocean Colour Imager (GOCI) to mapping SSS in the Korean coastal waters. Empirical relationships between CDOM absorption and SSS are derived from in-situ measurement collected at the Gyeonggi-bay located in the middle of the west coast of Korean peninsula. SSS images derived from GOCI were validated by comparison with the in-situ measurement and were also compared with SSS images provided from HYCOM-modelled, which shows that it is possible to estimate SSS from CDOM absorption at the estuarine environment. Further studies would be needed to improve the algorithm and apply it to other coastal environments around the Korean peninsula. Satellite based SSS from this study can be used for studies on the long-term variations in SSS in this area and its relations with the climate changes.