Like a lead violin tuning an orchestra, the GPM Core Observatory – launched one year ago on Feb. 27, 2014 as a collaboration between NASA and the Japan Aerospace Exploration Agency – acts as the standard to unify precipitation measurements from a network of 12 satellites. The result is NASA's Integrated Multi-satellite Retrievals for GPM data product, called IMERG, which combines all of these data from 12 satellites into a single, seamless map.
This first IMERG data set spans the initial months of GPM data collection from April to September, 2014. The precipitation data collected covers the 87 percent of the globe that falls between 60 degrees north and 60 degrees south latitude, updated every half hour.
The map covers more of the globe than any previous NASA precipitation data set, allowing scientists to see how rain and snowstorms move around nearly the entire planet. As scientists work to understand all the elements of Earth’s climate and weather systems, and how they could change in the future, GPM provides a major step forward in providing the scientific community comprehensive and consistent measurements of precipitation.