Every continent on Earth has lost more freshwater from its land area than ever measured since 2002, according to a new global study. The study paints an alarming picture for the world’s freshwater resources. In short, climate change, long-term, unsustainable groundwater pumping, and megadroughts are the key contributors to this crisis. This concerning trend seriously threatens food and water security for billions, including hundreds of millions of children—around the world.
It uses more than two decades of data from the US-German Gravity Recovery and Climate Experiment (GRACE). It folded in findings from its follow-on mission, GRACE-FO. Results indicate a major decrease in terrestrial water storage. Natural category This includes all surface and vegetation water, soil moisture, ice, snow, groundwater stored on land.
Jay Famiglietti, the study’s principal investigator, doesn’t mince words about the study’s most alarming finding. “These findings send perhaps the most alarming message yet about the impact of climate change on our water resources,” he stated. He pointed out, for example, that 15 million acres of land are drying up each year. They are on track to add annually an area about twice the size of California!
Drivers of Freshwater Loss
The study pinpointed five major drivers for the shocking amount of freshwater loss. Climate change becomes a major factor, creating new weather patterns that make droughts worse. Further, the unrealistic, unsustainable, inequitable extraction of groundwater to meet agricultural and urban needs is eviscerating the lifespan of these critical assets.
Hartley said that the loss of such a large volume of non-renewable water is staggering. “It is striking how much non-renewable water we are losing,” he said. This depletion has serious repercussions for future generations and calls into question whether we are sustainably managing our most vital resources.
The result is that since 2002, the only region to consistently see an average increase in moisture is the tropics. In stark contrast, regions around the world are experiencing drastically dwindling reserves of freshwater. The study revealed that 68% of water loss on land originates from groundwater depletion alone, contributing more to sea level rise than both the Greenland and Antarctic ice sheets combined.
Consequences for Global Populations
The effects of this loss of freshwater reach well beyond the ecological impacts of the hotspots. More than three-quarters of the world’s people reside within just 101 countries. These states have seen a steady elimination of freshwater habitats over the last 22 years. Famiglietti warns that “the consequences of continued groundwater overuse could undermine food and water security for billions of people around the world.”
The study shows the emergence of a tipping point discovered around 2014-15 during so-called “mega El-Niño” years. During this period, regions that were once wet began to dry significantly, while previously dry areas became wetter—a complete shift in hydrological patterns. The study identified four continental-scale mega drying regions: Southwestern North America and Central America, Alaska and Northern Canada, Northern Russia, and the Middle East-North Africa (MENA) Pan-Eurasia.
These alarming findings highlight an immediate and critical call to action. Famiglietti calls for a collective response: “This is an ‘all-hands-on-deck’ moment—we need immediate action on global water security.”
The Need for Sustainable Solutions
Even with formidable obstacles to averting the worst effects of climate change, specialists feel that powerful measures can still be taken to prevent continental drying. Making policy changes that prioritize regional and international groundwater sustainability can help dramatically reduce the rate of sea level rise. Taking this approach will help ensure that increasingly scarce water resources are preserved for future generations.
“This research matters. It clearly shows that we urgently need new policies and groundwater management strategies on a global scale,” he stated.
Chandanpurkar contrasted their positive story with what’s happening to the resources we already have. Glaciers and deep groundwater aquifers are kind of like ancient trust-funds. Too easily, we come to view such precious resources as an entitlement. Because they’re best used like that—beyond just moments of need such as a decades-long drought.
He mentioned that there is an urgent need to replenish groundwater systems during wet years rather than depleting them continuously. If we don’t act now, societies are headed for an immediate freshwater bankruptcy.