THIN ICE AREA EXTRACTION IN THE BERING SEA USING AMSR2 DATA

ABSTRACT: Due to the global warming, importance of monitoring sea ice distribution is increasing. Ice thickness is one of the most important parameters of sea ice. In thin ice areas, the heat flux of ice is strongly affected by the ice thickness difference. Thus, the extraction of thin ice area is quite important from global warming monitoring point of view. In 2014, the authors have developed an algorithm to detect thin ice area in the Sea of Okhotsk using the brightness temperature data derived from the passive microwave radiometer AMSR2 on board GCOM-W1 satellite. The basic algorithm is to use the brightness temperature scatter plots of AMSR2 19GHz polarization difference (V–H) vs 19GHz V polarization. In this study, we have investigated the possibility of applying the thin ice algorithm to the Bering Sea. Since the Bering Sea is located in higher latitude than the Okhotsk Sea, some parameter tuning of the algorithm was expected. The authors have examined the parameter of the algorithm and have verified the result by overlaying the extracted thin ice area on simultaneously observed MODIS images taken under the cloudless weather condition. The most of the thin ice areas were well extracted also in the Bering Sea