This GPS sensor on Greenland is one of nearly 50 spread across the island.
A network of GPS stations across southern Greenland has detected that the area lost 100 billion tons of ice due to an unusually warm summer in 2010, researchers report. What's more, removing that much weight has raised parts of the bedrock by a quarter inch more than in recent years.
Greenland's ice sheet has been seeing a steady melt during the summer months, and those GPS stations in years prior to 2010 typically detected an uplift of 0.59 inches.
"But a temperature spike in 2010 lifted the bedrock a detectably higher amount over a short five-month period -- as high as 20 mm (0.79 inches) in some locations," Ohio State University said in explaining the research by Michael Bevis, one of its geologists, and others that are part of the POLENET research network.
Bevis described the findings last Friday at a conference of the American Geophysical Union, saying he's convinced that the uplift is due to the ice loss.
"Really, there is no other explanation. The uplift anomaly correlates with maps of the 2010 melting day anomaly. In locations where there were many extra days of melting in 2010, the uplift anomaly is highest."
He added that the findings also have implications for sea levels.
"Pulses of extra melting and uplift imply that we'll experience pulses of extra sea level rise. The process is not really a steady process," he said.
Experts had earlier estimated that Greenland between 1961 and 2003 saw years that ranged from 25 billion tons of new ice to years where 60 billion tons were lost. Years since then have seen even higher shrinkage.
100 billion tons of ice melting from Greenland's ice sheet translates into a global sea level increase of about .01 inches.
The team first reported that ice sheets, which can be thousands of feet thick, suppress bedrock in 2008, when they discussed findings from similar GPS sensors on Antarctica.