The world’s precious stash of subterranean freshwater is shrinking — and in nearly a third of aquifers, that loss has been speeding up in the last couple of decades, researchers report in the Jan. 25 Nature.
A one-two punch of unsustainable groundwater withdrawals and changing climate has been causing global water levels to fall on average, leading to water shortages, slumping land surfaces and seawater intrusion into aquifers. The new study suggests that groundwater decline has accelerated in many places since 2000, but also suggests that these losses can be reversible with better water management.
It’s the first effort to synthesize global-scale groundwater data collected on site, rather than assessed by satellite. Previous studies have quantified the scope of global groundwater loss by analyzing data collected by a pair of NASA satellites known as GRACE. But while satellites can scan the entire globe, some of the nuance of water loss — and recovery — in regional aquifers can be hard to detect from space, the researchers say. [Continue reading…]