Precipitation Processing System (PPS) servers will be down for extended maintenance from Tuesday, September 22nd through Thursday September 24th. During this time the PPS websites, the PMM Publisher API, and the GPM research data server (arthurhou) will be unavailable. The GPM near real-time server (jsimpson) and satellite data collection will not be affected. Click here to learn more.

PMM

Content which is not specifically affiliated with GPM or TRMM, but which is about the Precipitation Measurement Missions in general.

GPM flying over Earth with a data swath visualized.
Freshwater seems abundant, but when accounting for all the water on Earth, it's in limited supply. Just three percent of the water on our planet is freshwater. A majority of this water, about two percent of the world total, is contained in glaciers and ice sheets or stored below ground. The remaining one percent is found in lakes, rivers and wetland areas or transported through the atmosphere in the form of water vapor, clouds and precipitation. Rain and snowfall replenish freshwater sources, making it vital to know when, where and how much water is falling at any given time. Using NASA's...