A global study published in the journal Science Advances shows that the loss of freshwater on Earth's continents is accelerating.

Scientists from Arizona State University analyzed satellite data from 2002 to 2024 and identified four continental regions experiencing severe drying:

• Southwestern North America and Central America: including important agricultural areas in the southwestern USA, desert cities like Phoenix, Tucson, and Las Vegas, and large metropolitan areas such as Los Angeles and Mexico City.

• Alaska and northern Canada: melting mountain glaciers in Alaska and British Columbia, thawing snow and permafrost in northern Canada, and drying key agricultural regions like British Columbia and Saskatchewan.

• Northern Russia: significant melting of snow and permafrost in high latitudes.

• Middle East, North Africa, and Pan-Eurasia: including large desert cities like Dubai, Casablanca, Cairo, Baghdad, and Tehran; important agricultural regions including Ukraine, northwest India, and the North China Plain; shrinking Caspian and Aral Seas; and major cities like Barcelona, Paris, Berlin, Dhaka, and Beijing.

The causes of increasing drought include climate change, overuse of groundwater, and extreme drought events. Researchers found that the area losing freshwater is increasing yearly at a rate roughly equal to the size of two Californias.

About 75% of the world’s population lives in 101 countries where freshwater reserves have been declining since 2002. Groundwater accounts for 68% of this loss, contributing more to sea level rise than the melting of glaciers in Greenland and Antarctica.

Professor Jay Famiglietti from Arizona State University warns that continents are drying, freshwater availability is shrinking, and sea levels are rising faster. He emphasizes the urgent need for action to prevent food and water insecurity for billions of people worldwide.

Lead author Hrishikesh Chandanpurkar highlights the alarming loss of non-renewable water sources like glaciers and deep groundwater, which are often treated as unlimited instead of being preserved for emergencies. He notes that groundwater is not being replenished during wet years, pushing the world toward inevitable water shortages.

The study also found that since 2014, dry areas have shifted toward the Northern Hemisphere, while wet areas have moved toward the Southern Hemisphere.

Satellite observations now allow scientists to clearly see long-term climate-driven trends. More ground monitoring and data sharing will help improve understanding and management of water resources.