Precipitation is the principal link between global water and energy cycles, weather and climate, and the activities of humankind. Natural and anthropogenic processes can alter the frequency, distribution, and magnitude of precipitating weather systems (e.g., the El Niño Southern Oscillation, urban heat islands, and deforestation). Changes in precipitation characteristics can affect Earth's energy balance through the redistribution of solar and terrestrial energy and latent heat fluxes. Planetary atmospheric circulation is largely driven by Earth's energy balance; thus, global precipitation patterns are a key element in climate variability. Therefore, the critical task is to continue to develop methods that allow for consistent, high-quality global observations of precipitation in order to gain better insight into the Earth system and weather and climate variability through improved forecasts. This ...