Scientists have discovered a vast reservoir of fresh water captured in layers of old snow buried near the surface of Greenland's vast ice sheet.
The reservoir, located in southeastern Greenland, is similar to a subsurface aquifer found on land. Its water remains liquid all year and covers an area about half the size of New York State.
Scientists can only theorize on why the water remains liquid year-round. But, researchers say, its surprising discovery could help scientists improve their estimates of how Greenland’s ice sheet, which has been losing mass at an increasing pace over the past two decades, will respond to global warming.
The pace of ice loss has accelerated quickly. The loss averaged 121 billion tons a year between 1993 and 2005, according to the Intergovernmental Panel on Climate Change. That pace increased to 229 billion tons a year between 2005 and 2010. Over the past two decades, the losses have raised average sea levels by 0.34 inches.
Scientists made the discovery in April 2011 as part of a three-year program known as Arctic Circle Traverse. The goal was to determine how much snow has fallen on Greenland over the past 30 to 60 years and how global warming has affected the rate of accumulation. The island's ice sheet results from the accumulation and compression of snow to form the ice, so understanding what gets added over time feeds into calculations of gains or losses to the ice sheet's overall mass.