THE OBJECTIVE OF THE PROPOSED RESEARCH IS TO IMPROVE ENHANCE AND CONTINUE THE SUPPORT FOR GPM ALGORITHMS CONDUCT VALIDATION AND ALSO OFFER A MAJOR ENHANCEMENT TO THE CLASSIFICATION MODULE FROM DPR NAMELY ADD A THIRD DIMENSION TO THE RETRIEVED PRODUCTS. WE WILL CONTINUE TO SUPPORT ANALYSIS TO STUDY PRECIPITATION MICROPHYSICAL PARAMETERS SUCH AS HYDROMETEOR AND PRECIPITATION TYPES AT GLOBAL AND REGIONAL SCALES TO DERIVE MICROPHYSICAL INFERENCES OF PRECIPITATION VARIATIONS AT THESE SCALES WITH THE MAIN GOAL OF ALGORITHM SUPPORT VALIDATION AND ENHANCEMENT FOR THE CLASSIFICATION MODULE FOR DPR. THESE STUDIES WILL BE CONDUCTED USING SPACE-BORNE OBSERVATIONS FROM THE GPM PLATFORM AS WELL AS GROUND DUAL-POLARIZATION RADARS AND IN-SITU OBSERVATIONS. SOME OF THE MOST IMPORTANT TASKS OF THE CURRENT PROPOSAL ARE A) VALIDATE THE PERFORMANCE OF THE NEW PRODUCTS INTRODUCED IN V7 THAT WILL BE RELEASED LATER THIS YEAR B) TEST AND VALIDATE THE EXISTING AND NEW DUAL-FREQUENCY PRODUCTS FOR INNER AND OUTER SWATH OF THE DPR PROFILE C) STUDY INTERNAL CONSISTENCY AND CONTRAST BETWEEN PRODUCTS AND D) PROVIDE A SIGNIFICANT LEAP BY ADDING THE THIRD DIMENSION TO THE CLASSIFICATION MODULE. IN ORDER TO MAKE AN IMPACT ON THE USE OF GPM OBSERVATIONS AND RETRIEVALS THE MICROPHYSICAL INFORMATION MUST BE CORRELATED TO THE SPACE-BORNE OBSERVATIONS. THE SPECIFIC ACTIVITIES IN THAT DIRECTION INCLUDE: A) SIMULATION OF GPM PRECIPITATION RADAR PROFILES FOR CATEGORIES OF MICROPHYSICAL SIGNIFICANCE B) THE DEVELOPMENT OF TECHNIQUES TO GENERATE MAPS OF HYDROMETEOR TYPES SUCH AS SNOW HAIL AND GRAUPEL AND COMPARE THEM AGAINST GROUND DUAL-POLARIZATION RADAR BASED RETRIEVALS AND C) MAKING USE OF THE ADVANCES IN STEPS (A) (B) TO IMPROVE GPM MICROPHYSICAL RETRIEVAL ALGORITHMS SPECIALLY VERTICAL PROFILE HYDROMETEOR CLASSIFICATION AT A GLOBAL SCALE. CURRENTLY OUR TEAM PLAYS A KEY ROLE IN THE DPR ALGORITHM DEVELOPMENT GROUP AND IS RESPONSIBLE FOR THE CLASSIFICATION MODULE AND HYDROMETEOR TYPE DEVELOPMENT (THAT INCLUDES THE SNOW INDEX MODULE GRAUPEL AND HAIL PRODUCTS) THAT HAS BEEN RELEASED AND OPERATIONAL. WE WILL CONTINUE TO TEST VALIDATE AND REFINE THE CLASSIFICATION MODULE AND INTRODUCE THE VERTICAL PROFILE OF HYDROMETEORS. THE PI AND THE TEAM PROPOSE TO CONTINUE TO PLAY THAT ROLE AND BE A PART OF THE INTERNATIONAL DPR ALGORITHM TEAM AND IN ADDITION PLAY A SIGNIFICANT ROLE IN THE ANALYSIS OF GROUND RADAR AND OTHER IN-SITU SAMPLING INFRASTRUCTURE FOR THE CROSS-VALIDATION OF HYDROMETEOR CLASSIFICATION AS WELL AS MIXED-PHASE PRECIPITATION STUDIES WITH SPACE-BORNE MEASUREMENTS FOCUSING ON THE MODULES UNDER DISCUSSION. GPM PRECIPITATION RADAR OBSERVATIONS COMBINED WITH THE KNOWLEDGE OF PRECIPITATION MICROPHYSICS OBSERVED ON THE GROUND WORLDWIDE PROVIDE A SOUND BASIS FOR MODELING THE PRECIPITATION OBSERVATIONS FOR SPACE-BORNE SYSTEMS. WE PROPOSE THE USE OF OBSERVATIONS-BASED SIMULATIONS AS WELL AS GROUND-BASED DUAL POLARIZATION AND DUAL-FREQUENCY RADAR OBSERVATIONS TO DEVELOP DATA-BASED MODELS TO EVALUATE THE SPACE-BORNE DUAL-FREQUENCY RADAR OBSERVATIONS. CONTINUOUS EDUCATIONAL OUTREACH ASSOCIATED WITH THE RESEARCH WILL BE AN INTEGRAL FEATURE OF THIS PROPOSAL.