Many shifts are apparent as climate change grips the Earth, from higher average temperatures, to rising sea levels to reduced snowpack, but one water resource-related impact that has been less understood is groundwater. Harnessing new readings and data models, a recent study was published in Nature Climate Change, which found that in many places around the world, hotter weather and declining rainfall influenced by climate change is slowing aquifer replenishment.
“Our research shows that groundwater systems take a lot longer to respond to climate change than surface water, with only half of the world’s groundwater flows responding fully within ‘human’ timescales of 100 years,” says study co-author, Mark Cuthbert from the UK’s Cardiff University.
Groundwater, which is store in soil and rocks, are considered underground water reserves even though their time horizons are much longer compared to surface waters’ responsiveness. The scientists note that the time delay on groundwater replenishment has the potential to make groundwater levels lower and increase the probability of water shortages. This future scenario was dubbed a “time bomb,” one in which shrinking water supplies can’t meet human demand.
As Cuthbert warned, “It is essential that the potential for these initially hidden impacts is recognized when developing water management policies, or climate change adaptation strategies for future generations.”