We keep hearing melting ice is causing sea levels to rise. Don't worry -- this isn't another post convincing you it's happening. But the idea makes sense: if ice melts, the water's got to go somewhere. The scary thing about global ice melting is just how much water that would create. There is a lot of ice on the planet -- around 6 million cubic miles. Each cubic mile of ice contains a trillion gallons of water. It's almost impossible to comprehend that much water. If it all melts, the Earth would drown in 7 quintillion gallons of water. Not every day you get to use the number "quintillion". It's enough water to cover the continental United States -- 2,000 feet deep.
But this isn't a post about that. Because researchers from Arizona State University and the Jet Propulsion Laboratory just discovered something much worse.
The study, published this month (July, 2025) in the journal Science Advances, is called, "Unprecedented continental drying, shrinking freshwater availability, and increasing land contributions to sea level rise" (another catchy title from the world of science). The study was made possible by a NASA satellite mission called GRACE (Gravity, Recovery, and Climate Experiment), launched over twenty years ago. The mission's goal was to measure the global movement of water based on changes in the Earth's gravity field. It actually works. When water shifts around the globe, it affects the Earth's mass, which changes the gravitational pull ever so slightly.
The GRACE mission used two satellites flying 140 miles apart. As they orbited Earth, tiny changes in the distance between them were precisely measured. Every change meant mass was shifting, which in turn meant water was moving around the planet. Wherever there were melting glaciers, depleting groundwater, droughts or floods, changes in snowpack or soil moisture -- any significant water movement above or below ground -- GRACE tracked it.
Researchers analyzed the data from the GRACE mission, which ran from 2002 to 2017, along with the current follow-up mission, GRACE-FO, launched in 2018. They expected to find the ice sheets were melting. But they found more than that. The satellite data showed a major crisis unfolding.
The first shock: the land under our feet is drying out at an alarming rate. The surface water, soil moisture, snow, ice, and any other groundwater is disappearing. Since 2002, areas drying out increased by over 300,000 square miles a year. That means, every year, an area twice the size of California is losing its stores of fresh water, trending toward no water at all.
The second shock: the overall change wasn't driven by glaciers melting. It was driven by water lost from land. Drying continents add more water to rising seas than melting ice sheets. And it's getting worse in the last decade. Since 2014, the area of non-glaciated land experiencing extreme drying has increased by over a million square miles every year. That means that -- not including glaciers -- we're losing fresh water in an area ten times the size of the United Kingdom every single year. In fact, non-glaciated drying areas accounted for 68% of the loss in Terrestrial Water Storage (TWS).
So what the heck is going on? One big issue is we're using too much groundwater. It may seem like when you turn on the faucet, water will always be there. But the fact is, it can run out. This review of NASA's data shows that's exactly where we're headed.
About half the world's drinking water and most of its irrigation water comes from stores in the ground called "aquifers". In many regions experiencing continental drying, aquifers are being drained faster than they can recover. Heavily depleted aquifers include California's Central Valley and the southern Ogallala Aquifer (one of the world's largest, covering Texas, New Mexico, Oklahoma, Kansas, and Colorado). Globally, extreme drying aquifers include the Northwestern Sahara Aquifer System, Arabian Aquifer System, and the Tarim, Indus, Ganges-Brahmaputra, and North China Basins in South and East Asia. These heavily stressed aquifers represent more than half the area of all aquifers on the planet.
In fact, the study uncovered a larger change in the Earth itself. The drying aquifers combined with melting ice and extreme droughts are actually changing the landscape. The study identifies four continental-scale Mega-Drying Regions, formed by the interconnection of previously identified drying hotspots. The Mega-Drying regions are Northern Canada/Russia, Southwestern North America/Central America, the Middle East/North Africa/Pan-Eurasia (this one is a massive tri-continental region extending from North Africa to Europe, the Middle East, Central Asia, and northern China), and lastly, Southeast Asia. The Earth is transforming into enormous, connected deserts.
75% of the global population now live in countries that are losing freshwater with no end in sight. Indeed, the conclusions of the study are dire. The researchers are not expecting trends to bounce back. According to the study, the drying regions are "likely to persist in the near future," and the "critical shift in the behavior of TWS and continental drying following the major El Niño beginning in 2014, may well mean that reversing these trends is unlikely." The findings represent "perhaps the direst message on the impact of climate change to date."
Not an uplifting study.
In 2025, Mercy Corps reported that the city of Kabul will be the first major capital to actually run out of water. They say it could happen as soon as 2030. Kabul's aquifers have dropped 25--30 meters in just the past decade due to over-extraction and climate stress. Nearly half of the city's boreholes -- the main sources of drinking water -- are already dry.
Is it time to prepare for the global water wars?
The Arizona State study does offer positive answers. Better groundwater management, new public policy to elevate awareness and action around the issue, innovative strategies to store more water on land -- all things that don't seem to be a priority to anyone in power to act on the growing crisis.
In 2024, NASA's Perseverance Rover found rocks in the Jezero Crater on Mars that were shaped by ancient water. The find is solid proof that liquid water was abundant on ancient Mars. As of now, we haven't found any still there. Not in liquid form.
Used to be the search for water on Mars was just a scientific curiosity. It's starting to look like we may actually need it.