Hurricane Precipitation Retrieval Using FY-3C MWRI Brightness Temperature

A rainfall retrieval algorithm for tropical cyclones based on dual-polarized brightness temperature (Tb) from the Fengyun 3C (FY-3C) Microwave Radiation Imager (MWRI) radiometer is presented. Since the nonlinear relationship between rain rate and Tb, the “beamfilling effect” is corrected to make the liquid water absorption closer to the Mie absorption. The rain rate retrieval is based on the unique relationship between liquid water absorption and rain rate. To evaluate the performance of MWRI retrievals, hurricane Jose is chosen as the case study, and the Global Precipitation Measurement (GPM) Dual-frequency Precipitation Radar (DPR) rainfall product is used as a reference dataset. The MWRI retrieved rain rates show good consistency with DPR product in hurricane Jose rainfall distribution and statistical comparison, with total bias and RMS of 0.24 mm/h and 2.36 mm/h, respectively.