Status and Development of Version 08 in the NASA GPM Activities

The joint U.S.-Japan Global Precipitation Measurement (GPM) mission has passed a decade of operations, and continues to pursue research, dataset production, and outreach related to precipitation.  One key activity currently in development is the release of an improved “Version 08” of all GPM precipitation and latent heating products.

This presentation summarizes key improvements to the GPM products for which NASA has lead responsibility as we approach the release of Version 08.  For example, the Goddard Profiling (GPROF) algorithm has implemented a Machine Learning-based algorithm that shows solid improvements in computing retrievals from the constellation of partner satellite passive microwave sensors when compared to the GPM Microwave Imager (GMI) retrievals.  And all of the PMW retrievals, including from GMI, show improved validation scores.  The Combined Radar Radiometer Algorithm (CORRA) now incorporates additional emphasis on GMI (and Tropical Rainfall Measuring Mission [TRMM] Microwave Imager [TMI]) data in regions where the radar lacks skill.  This is principally the light precipitation and snow at high latitudes and over Central Asia in the winter.  Each algorithm is being adjusted to ensure continuity for each product across the boundary in 2014 between the TRMM and the GPM eras, as well as across the TRMM and GPM Core Observatory orbit boosts.  The U.S. Science Team’s Integrated Multi-satellitE Retrievals for GPM (IMERG) was upgraded to give more flexibility in using different-quality PMW sensors, and a new ML-based retrieval has been

The presentation also considers major issues that require continued attention, including the operational challenge of swarms of “small”, perhaps short-lived satellites, and planning for the next-generation multi-satellite product.