Development of the DPR algorithms and products for GPM

Global Precipitation Measurement (GPM) started as an international mission and follow-on and expand mission of the Tropical Rainfall Measuring Mission (TRMM) project to obtain more accurate and frequent observations of precipitation than TRMM. The TRMM satellite achieved ten-year observation in November 2007, and is still operating to measure tropical/subtropical precipitation. An important goal for the GPM mission is the frequent measurement of global precipitation using a GPM core satellite and a constellation of multiple satellites. The accurate measurement of precipitation will be achieved by the Dual-frequency Precipitation Radar (DPR) on the GPM core-satellite, which is being developed by Japan Aerospace Exploration Agency (JAXA) and National Institute of Information and Communications Technology (NICT) and consists of two radars, which are Ku-band precipitation radar (KuPR) and Kaband radar (KaPR). KaPR will detect snow and light rain, and the KuPR will detect heavy rain. In an effective dynamic range in both KaPR and KuPR, drop size distribution (DSD) information and more accurate rainfall estimates will be provided by a dual-frequency algorithm. The frequent precipitation measurement every three hours at any place on the globe will be achieved by several constellation satellites with microwave radiometers (MWRs). JAXA/EORC is responsible for the GPM/DPR algorithm development for engineering values (Level 1) and physical products (e.g. precipitation estimation) (Level 2 and 3) and the quality control of the products as the sensor provider. It is also important for us to produce and deliver frequent global precipitation map in real time in order to make useful for various research and application areas (i.e., the prediction of the floods).