Large, All-Year-Round Water Reservoir Found Beneath Greenland Ice Sheet

University of Utah researchers have found a vast aquifer measuring 27,000 square miles in Greenland. The waterbody, which is about the size of the state of West-Virginia, doesn't freeze even during winters.

The water reservoir will probably help scientists predict the temperature and movement of water within the ice sheet in Greenland with more precision

No scientific model accounts for this perennial water reservoir, meaning that scientists might have to relook ice loss calculations in the region.

The aquifer is known as "perennial firn aquifer" because water stays within firn- layers of snow that don't melt during summer.

Rick Forster, professor of geography at the University of Utah, and team has been studying southeast Greenland since 2010. Two years back, they found that two of their drills used for collecting ice core samples hit water. They found water some 33 feet below in the first drill hole and 82 feet in the second hole.

"This discovery was a surprise," Forster said in a news release. "Although water discharge from streams in winter had been previously reported, and snow temperature data implied small amounts of water, no one had yet reported observing water in the firn that had persisted through the winter."

A NASA plane equipped with terrain-mapping radar was sent to survey the region. Researchers even brought snow penetrating radar towed by a snowmobile, AFP reported. The radar showed a vast expanse of water beneath ice.

The aquifer is quite similar to one found on land. But, unlike water reservoirs on land, the water in Greenland is held within packs of snow that haven't melted in the past seasons. It's like finding juice at the bottom of a snow-cone, researchers said.

"The surprising fact is the juice in this snow cone never freezes, even during the dark Greenland winter. Large amounts of snow fall on the surface late in the summer and quickly insulates the water from the subfreezing air temperatures above, allowing the water to persist all year long," Foster said.

Relooking Ice Loss in Greenland

The Greenland Ice Sheet is about 1,500 miles long and 680 miles wide, which makes it second largest ice sheet in the world. If all this ice were to melt entirely in a day, the global sea-levels would rise by 24 feet.

Until now, models to calculate ice loss assumed that the meltwater was either flowing into the sea or was refrozen. The discovery of a large water reservoir means that scientists would have to now account for the water that flows into this aquifer.

The aquifer's role in Greenland Ice-sheet melt is still a mystery. The reservoir may help conserve meltwater and reduce flow. But, it could also act as a lubricant to ease glacial movement and increase ice-calving.

The aquifer itself might not be a result of climate change. Researchers said that simulations of Greenland Ice Sheets show that reservoir might have existed for several decades.

The study is published in the journal Nature Geoscience.

Two subglacial lakes were earlier found in Greenland, suggesting that not all ice that melts during summer goes into the oceans. Ice sheets in Antarctica are known to be pock-marked with several subglacial lakes, which fill and drain like a bathtub. Understanding how much water flows into these icy tubs is essential in tracking the movement of ice in the region.