Land and Sea Ice Mask Optimization for Scanning Microwave Radiometer of HY-2B Satellite

China's Haiyang-2B satellite (HY-2B) has been in orbit for over a year, since it was launched on October 25th, 2018. HY-2B is equipped with both active and passive microwave remote sensors. Payload named scanning microwave radiometer (SMR) with five frequency channels in HY-2B is an instrument mainly used to monitor and investigate ocean environment and obtain ocean dynamic parameters like sea surface temperature, surface wind speed, atmospheric water vapor and cloud liquid water, etc. This paper introduce a method to optimize the masks of land and sea ice based on HY-2B SMR in order to improve the inversion accuracy of sea surface temperature. The idea of the method is subdividing the 3dB footprint into more sophisticated points, and every point is geolocated and marked as Land, Sea water or Sea ice. Finally, the subdivided mask is used for SST inversion and compared with the WINDSAT SST inversion results of the Coriolis satellite. The chosen of the method's parameters will compromise between numbers available for inversion and inversion accuracy.