University of Utah researchers however, have discovered a new reservoir/aquifer in Greenland’s ice sheet. The reservoir is known as a "perennial firn aquifer" and covers 27,000 square miles an area larger than the state of West Virginia. Called a firn because water persists within layers of snow and ice that doesn’t melt for at least one season, researchers believe the discovery will aid in the understanding of snowmelt and ice melt as it relates to rising sea levels.
"Of the current sea level rise, the Greenland Ice Sheet is the largest contributor — and it is melting at record levels," says Rick Forster, lead author and professor of geography at the University of Utah. "So understanding the aquifer's capacity to store water from year to year is important because it fills a major gap in the overall equation of melt water runoff and sea levels."
In 2010, the team drilled core samples in three locations and returned in 2011 to approximately the same area, but at lower elevation. Two of the four core samples taken in 2011 came to the surface with liquid water pouring off the drill amidst air temperatures of minus 4 degrees Fahrenheit. Water was found at 33 feet below surface at the first hole and at 82 feet in the second.
The aquifer is similar in form to groundwater potable aquifers on land accept that water is stored in the airspace between ice particles, like the juice in a snow cone instead of between rocks. Forster adds. "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."
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