Study: One-third of big groundwater basins in distress

About one third of Earth's largest groundwater basins are being rapidly depleted by human consumption, despite having little accurate data about how much water remains in them, according to two new studies led by the University of California, Irvine (UCI), using data from NASA's Gravity Recovery and Climate Experiment (GRACE) satellites.

This means that significant segments of Earth's population are consuming groundwater quickly without knowing when it might run out, the researchers conclude. The findings are published today in Water Resources Research.

"Available physical and chemical measurements are simply insufficient," said UCI professor and principal investigator Jay Famiglietti, who is also the senior water scientist at NASA's Jet Propulsion Laboratory in Pasadena, California. "Given how quickly we are consuming the world's groundwater reserves, we need a coordinated global effort to determine how much is left."

The studies are the first to comprehensively characterize global groundwater losses with data from space, using readings generated by NASA's twin GRACE satellites. GRACE measures dips and bumps in Earth's gravity, which are affected by the mass of water. In the first paper, researchers found that 13 of the planet's 37 largest aquifers studied between 2003 and 2013 were being depleted while receiving little to no recharge.