CAMBRIDGE, England, Nov. 28 (UPI) -- Lakes discovered beneath the Greenland ice sheet are the first subglacial lakes to be identified there although they're common in Antarctica, researchers say.
In a study published in Geophysical Research Letters, British scientists report the discovery of two such lakes 2,600 feet below the ice sheet. Each lake is roughly 3-to-4 square miles in size, although in the past they may have been as much as three times larger, they said.
Airborne radar measurements revealed the lakes underneath the ice in a study by the Scott Polar Research Institute at the University of Cambridge.
"Our results show that subglacial lakes exist in Greenland, and that they form an important part of the ice sheet's plumbing system," said Steven Palmer, formerly with the Cambridge institute and now at the University of Exeter. "Because the way in which water moves beneath ice sheets strongly affects ice flow speeds, improved understanding of these lakes will allow us to predict more accurately how the ice sheet will respond to anticipated future warming."
The newly discovered lakes are most likely fed by melting surface water draining through cracks in the ice, and a surface lake situated nearby may replenish them during warm summers, the researchers said.
That means the lakes are part of an open system and are connected to the surface, which is different from Antarctic lakes that are most often isolated ecosystems.
Nearly 400 lakes have been detected beneath the Antarctic ice sheets.