Precipitation characteristics over land from the NOAA-15 AMSU sensor

Window channel measurements from the NOAA-15 Advanced Microwave Sounding Un it (AMSU) are used to retrieve rain rates. This study focuses on the rain r ate retrievals over land and uses measurements at 89 and 150 GHz to detect a scattering signal by millimeter-sized ice particles under precipitating a tmospheres. An operational algorithm using the AMSU-A module (89 GHz) imple mented in August 1999 is also described. The algorithms are calibrated with hourly surface rain observations. It is shown that identification of strat iform rain can be dramatically improved using measurements at 150 GHz from the AMSU-B sensor. Improved spatial resolution of AMSU-B is a major factor contributing to this algorithm.