Regional Profiles and Precipitation Retrievals and Analysis Using FY-3C MWHTS

Abstract

The 89 and 150 GHz channels operated in window are sensitive to precipitation and humidity. The 183 GHz humidity-sensitive channels and 118 GHz temperature-sensitive channels of the Microwave Humidity and Temperature Sounder (MWHTS) on the Chinese Feng Yun 3C MWHTS (FY-3C MWHTS) polar-orbit meteorological satellite responds in part to precipitation. Combining 118 and 183 GHz channels, the paper develops a passive sub-millimeter atmospheric profile and precipitation retrievals algorithm for MWHTS onboard the FY-3C (Feng Yun-3C) satellite. The retrieval algorithm employs a number of back propagation neural network estimators trained and evaluated using the validated global reference physical model NCEP/WRF/ARTS and works for land and seawater with latitude between -40 to 40 degree. NCEP data per 6 hours were downloaded to run the Weather Research and Forecast model WRF, and to derive the typical precipitation data for the whole world. The Atmospheric Radiative Transfer Simulator ARTS is feasible for performing simulations of atmospheric radiative transfer. The results show that the profile retrievals using BP-NN algorithm has the best correlation with those from radiosonde, which is less than 18% and 1 K of root mean square error, respectively. For precipitation rate retrievals, a much better agreement is reached with rain gauge and ECMWF datasets, the RMS is between 0.80 to 30.24 mm/h for sea surface and 0.789 to 33.11 mm/h for land surface according to the classification by precipitation type. Also, the analysis of retrievals located in Tibetan plateau is provided as an example to justify the robustness and performance of retrieving model.