As climate change alters the world around us, scientists are warning that the impacts on groundwater reserves could take a century to catch up – which means it'll be our grandchildren dealing with the fallout of the effects on their water supply.
Groundwater – fresh water cached underground in soil and between rocks – takes much longer to respond to temperature changes than surface water, the researchers point out.
We rely on rain to keep groundwater stocked up, which means areas seeing hotter weather and less rainfall are going to be lighting the fuse for a future 'timebomb' in which water supplies can't keep up with demand. The time delay potentially makes these 'hidden' shortages even more dangerous.
"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 one of the team, Mark Cuthbert from Cardiff University in the UK.