Freshwater resources on Earth are rapidly decreasing, putting the stable supply of drinking water and food at risk.

Freshwater is an essential resource not only for drinking but also for agriculture, industry, etc. However, a research team including Arizona State University analyzed the trends in the world's freshwater reserves and found that freshwater reserves have rapidly decreased since the 2000s.

Unprecedented continental drying, shrinking freshwater availability, and increasing land contributions to sea level rise | Science Advances

https://news.asu.edu/20250725-environment-and-sustainability-new-global-study-shows-freshwater-disappearing-alarming

The research team analyzed changes in the world's freshwater reserves based on data obtained from the GRACE mission, a joint Earth gravity observation mission conducted by the National Aeronautics and Space Administration (NASA) and the German Aerospace Center (DLR), and its successor mission , GRACE-FO .

The figure below shows the change in global freshwater storage from March 2003 to April 2024. Red indicates a decrease in freshwater storage, while blue indicates an increase. The areas where freshwater storage decreased tended to be concentrated in the Northern Hemisphere, with particularly notable decreases in freshwater storage in four regions: Southwestern North America and Central America, Alaska and northern Canada, northern Russia, and the Middle East and North Africa.

The chart below summarizes the changes in freshwater reserves by country. It was revealed that 101 countries have declining reserves, and that approximately 75% of the world's population lives in countries with declining freshwater reserves.

Furthermore, an analysis of the causes of the decline in freshwater reserves revealed that 68% of the decline was due to 'groundwater decline.' Since groundwater decline is primarily caused by sea level rise, it is possible that freshwater reserves will continue to decline in the future.

'Continents are drying out, freshwater resources are declining, and sea levels are rising at an accelerating rate. Continued overexploitation of groundwater could threaten the food and drinking water security of billions of people around the world,' said Jay Famiglietti , a member of the research team. 'Now is the time for 'all hands on deck' - urgent action is needed for global water security.'