Using coincident SSM/I and infrared geostationary satellite data for rapid updates of rainfall

There exists a need for rapid updates of land and ocean-based precipitation within the atmospheric, oceanographic, and hydrologic communities. While presenting their own difficulties, satellite observations overcome many of the difficulties encountered in obtaining observations near coasts and over oceans. The current microwave-based Special Sensor Microwave Imagers (SSM/I) provide global coverage of rainfall from a polar-orbiting perspective. Conversely, operational geostationary imagers such as the Geostationary Operational Earth Satellites (GOES) provide rapid hourly (or less) updates in the infrared (IR) spectrum near 11 microns, which for optically thick clouds senses the emitted radiation from the upper cloud regions. This technique attempts to statistically fuse these two types of disjoint satellite data together in a real-time fashion for retrieval of instantaneous rain rate as well as accumulations at the geostationary update cycle. The technique works with any of the four current operational geostationary imagers (GOES-8, GOES-9, GMS 5 and Meteosat-6), and is easily adaptable to assimilate rain rates derived from the Tropical Rainfall Measuring Mission (TRMM) microwave imager (TMI)