Assimation of FY3D Combined Microwave Sounder Observation in ATMS Alike One Data Stream

Several deliberate treatments are performed to assimilate the microwave sounding observation onboard Chinese polar meteorological satellite FY3D in numerical weather prediction (NWP). The two missing channels of frequency at 23.8 and 31.4 GHz are reconstructed to help the implement of quality control (QC) including the estimation of satellite based cloud liquid water (CLW) and total perceptible water (TPW). Special attention is paid to the significant scan-dependent bias in FY3D microwave temperature observation in bias correction. In addition, the combined microwave sounder (CMWS) data is adopted to use the temperature and humidity observations coherently in ATMS alike one data stream. It is shown that the numerical forecast of typhoon is improved by the assimilation of FY3D CMWS observation.