Satellites identify 40 regions where people alter terrestrial water storage

A NASA-led study combined GRACE and GRACE-FO gravity measurements from April 2002 through November 2025 and mapped long-term terrestrial-water-storage trends at five-to-ten times the spatial detail of previous analyses. It identified 40 regions on every nonpolar continent except Australia where storage change was significantly associated with human activity, including groundwater irrigation, reservoir filling, canals and land-use change. Storage declined with pumping in California's Central Valley, the southern US High Plains, Chihuahua and northern India, while increases appeared in some rainfed African farmland, Brazil's Maranhao state and major Russian reservoirs. The method sacrifices some temporal resolution, and statistical association does not establish one cause everywhere. Next, researchers plan to combine it with monthly products to follow drought and policy effects over time.