Arctic lakes are drying out nearly a century earlier than projected, depriving the region of a critical source of fresh water, according to new research.
Models had predicted that as warmer weather thaws the Arctic, melting ice would feed into lakes, causing them to expand. Eventually, as ice melted away, those lakes would drain and dry out, sometime later this century, according to earlier projections. But satellite imagery reveals that lakes across the Arctic are shrinking rapidly today.
Researchers tracked a distinct downward trend in Arctic lake cover from 2000 to 2021, observing declines across 82 percent of the study area, which included large swaths of Canada, Russia, Greenland, Scandinavia, and Alaska. As warmer air and more abundant autumn rainfall melt permafrost around and beneath Arctic lakes, water is draining away, scientists say. The effect of rainfall was unaccounted for in prior models, which showed the lakes draining much later. The study was published in the journal Nature Climate Change.
The sooner-than-expected loss of surface water could have a profound effect, scientists say. Lakes comprise 20 to 40 percent of Arctic lowlands, serve as a critical habitat for migratory birds and other wildlife, and supply freshwater to remote Arctic communities.
The climate implications of rapidly melting permafrost are also troubling, researchers say. “Permafrost soils store nearly two times as much carbon as the atmosphere,” Elizabeth Webb, a postdoctoral researcher at the University of Florida and lead author of the study, said in a statement. “There’s a lot of ongoing research suggesting that as permafrost thaws, this carbon is vulnerable to being released to the atmosphere in the form of methane and carbon dioxide.”