Science

A NASA-backed study offers a sharper way to model Antarctica's Thwaites Glacier, which already contributes to sea-level rise. Instead of treating where ice lifts off the ground as one line, the model represents a wider grounding zone where seawater can move beneath the ice during tides. In simulations, that change matched satellite records from the 1990s about four times more closely than models without it. Some runs projected up to twice the sea-level contribution by century's end. That is a model result, not a locked forecast: future warming and ice-ocean processes still matter.

A peer-reviewed study used more than two decades of NASA gravity-satellite data to map long-term changes in water stored on land. The researchers found 40 regions where trends were strongly linked with human activities, including irrigation, reservoirs, and land-use change. In places such as California's Central Valley and northern India, groundwater-dependent farming was associated with declining water storage. The study does not say every local change has one cause. It uses statistics to separate likely human influence from climate factors, while the satellite data show broad long-term patterns rather than a real-time view of one community.