Analysis and Evaluation of GPM Pre-launch Algorithms

The Global Precipitation Measurement (GPM) mission is the next satellite mission to obtain global precipitation measurements following success of TRMM (Tropical Rainfall Measuring Mission). GPM will be launched on February 28, 2014. The GPM mission architecture consists of satellite instruments flying within a constellation to provide accurate precipitation measurements around the globe every 2 to 4 hours and the its orbits cover up to 65 degree latitude of the earth. The GPM core satellite will be equipped with a dual-frequency precipitation radar (DPR) operating at Ku(13.6 GHz) and Ka(35.5 GHz) band. DPR on aboard the GPM core satellite is expected to improve our knowledge of precipitation processes relative to the single-frequency (Kuband) radar used in TRMM by providing greater dynamic range, more detailed information on microphysics, and better accuracies in rainfall and liquid water content retrievals. New Kaband channel observation of DPR will help to improve the detection thresholds for light rain and snow relative to TRMM PR. The dual-frequency signals will allow us to distinguish regions of liquid, frozen, and mixed-phase precipitation.