Several regions around the world are seeing marked declines in water availability, according to a paper published in the journal Science Advances on July 25. The study, partially funded by NASA, found that dry areas are increasing by about twice the size of California each year.

Researchers identified the trend using data collected from 2002 to 2024 by two U.S.-German missions called the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO).

One of the regions includes an area stretching from southwestern North America to Central America, where dry conditions are becoming more common. The expansion of a recent European drought has produced a mega-drying region that stretches from North Africa to Europe, through the Middle East and Central Asia, and into northern China and Southeast Asia.

The study authors also found that most of the wet areas on Earth are getting wetter, including parts of East Africa and western sub-Saharan Africa. But those regions aren’t getting wetter as fast as the dry regions are drying out.

Quelle: NASA