Satellites reveal sharp decline in freshwater reserves across continents

The study, published in the journal Proceedings of the National Academy of Sciences, analyzed satellite measurements from April 2002 to November 2025. Researchers used data from NASA's GRACE and GRACE Follow-On missions, which track changes in Earth's gravity to detect shifts in the amount of water stored on and beneath the land.

Using a higher-resolution method, the researchers identified 94 regions with significant changes in water storage. In 40 of them, the trends were associated with human activities such as groundwater pumping, irrigation, dam construction, deforestation and changes in land use.

Across those 40 regions, total water losses reached about 3,122 billion tons, compared with gains of 2,432 billion tons. The new analysis found that earlier methods had underestimated the scale of regional changes by an average of 33%.

Groundwater depletion was particularly severe in major agricultural regions, where underground reserves are heavily used for irrigation. Northern India, southern Iran and the southern U.S. High Plains were among the areas showing pronounced losses. These regions rely heavily on aquifers to support farming and local water supplies.

The study found that human land and water use had a significant influence on water storage trends across every nonpolar continent except Australia. Groundwater irrigation was especially closely linked to declining reserves.

Researchers said the sharper satellite picture shows that freshwater depletion, particularly from groundwater pumping, is more severe than previously estimated. The findings raise concerns for agriculture and communities that depend on underground water reserves, especially as falling water tables can make wells more expensive to operate or cause them to run dry.

Earlier, Qazinform News Agency reported that NASA found evidence of repeated water activity on Mars.