Bulletin of American Meteorological Society | Skofronick-Jackson et al. 
The Global Precipitation Measurement (GPM) mission collects essential rain and snow data for scientific studies and societal benefit.
Precipitation is a key source of freshwater; therefore observing global patterns of precipitation and its intensity is important for science, society, and understanding our planet in a changing climate. In 2014, NASA and the Japan Aerospace Exploration Agency (JAXA) launched the Global Precipitation Measurement (GPM) Core Observatory (GPM-CO) spacecraft. The GPM-CO carries the most advanced precipitation sensors currently in space including a dual-frequency precipitation radar provided by JAXA measuring the three-dimensional structures of precipitation and a well-calibrated, multi-frequency passive microwave radiometer providing wide-swath precipitation data. The GPM-CO was designed to measure rain rates from 0.2-110.0 mm h-1 and to detect moderate to intense snow events. The GPM-CO serves as a reference for unifying the data from a constellation of partner satellites to provide next-generation, merged precipitation estimates globally and with high spatial and temporal resolutions. Through improved measurements of rain and snow, precipitation data from GPM provides new information such as: details on precipitation structure and intensity; observations of hurricanes and typhoons as they transition from the tropics to mid-latitudes; data to advance near-real-time hazard assessment for floods, landslides and droughts; inputs to improve weather and climate models; and insights into agricultural productivity, famine, and public health. Since launch, GPM teams have calibrated satellite instruments, refined precipitation retrieval algorithms, expanded science investigations, and processed and disseminated precipitation data for a range of applications. The current status of GPM, its ongoing science, and future plans will be presented.
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