USE OF THE GPM CONSTELLATION FOR MONITORING AND ANALYSIS OF HEAVY PRECIPITATION EVENTS IN ITALY DURING FALL 2014

With the recent advent of the NASA/JAXA Global Precipitation Measurement (GPM) mission a new era has started for precipitation monitoring. The satellite constellation carrying passive microwave (PMW) radiometers ensures a 3-hourly global coverage. The first spaceborne dual-frequency precipitation radar (DPR), along with the advanced GPM Microwave Imager (GMI), onboard the GPM core satellite, are the reference instruments for precipitation retrieval providing consistency around the globe. However global monitoring of the precipitation requires the full exploitation of all overpasses of present and future satellites carrying cross-track and conically scanning PMW radiometers. To monitor the evolution of heavy precipitation systems occurred during fall 2014 in Italy, precipitation retrievals exploiting the available overpasses of PMW radiometers are used in this study. Two different physically-based retrieval algorithms (CDRD for SSMIS and PNPR for AMSU/MHS and ATMS) are used in conjunction with official NASA/JAXA GPM instantaneous precipitation products (for AMSR-2 and GMI). The CDRD and PNPR algorithms are used operationally within the EUMETSAT H-SAF program (Satellite Application Facility on Support to Operational Hydrology and Water Management, http://hsaf.meteoam.it) to provide instantaneous precipitation rate estimates over the full Meteosat Second Generation (MSG) full disk area. The comparison with radar observations at ground evidences the ability of the different sensors to identify different precipitation areas and regimes. In spite of their low spatial resolution and relatively poor temporal sampling PMW precipitation retrievals from CDRD and PNPR, specifically designed for the Mediterranean area, provide good estimate of total precipitation amounts, also in presence of complex orography and in proximity of the coast.