WHAT THE EVIDENCE SAYS
The World Meteorological Organization’s State of Global Water Resources 2025 synthesizes member observations, hydrological models and satellite data across river discharge, groundwater, evapotranspiration, terrestrial water storage, snow and ice. It reports 2025 among the driest river-discharge years in 35 years, the fewest normal-flow years over the past seven years since records beginning in 1991, declining land-water storage over the past decade and glacier loss in every region for a fourth straight year.
WHY IT MATTERS / OUR READ
The important signal is not simply that 2025 was dry. The reference condition itself is becoming more volatile, so water planning that assumes a stable historical range can underestimate both scarcity and excess-water risk. Ecological planning increasingly needs basin-scale storage, flow variability and extremes together rather than precipitation or annual averages alone.
CAVEATS / UNCERTAINTY
Coverage and data quality still vary among basins, and the report combines observations with modeled and satellite products. A global synthesis identifies broad hydrological change but does not replace local groundwater, streamflow or ecological-flow assessment.
SOURCE
World Meteorological Organization · State of Global Water Resources 2025
View original evidence ↗