Khan and colleagues from the University of Colorado, US, the University of Maine, US, and the University of Luxembourg found that between 2001 and 2006, rapid unloading of ice from the south-eastern sector of the Greenland ice sheet caused an elastic uplift of around 35 mm at a GPS site in Kulusuk.
“We decided to pursue this approach because usage of GPS to study ongoing climate change is new,” said Khan. “By measuring uplift of the bedrock we are able to give an estimate of the ice mass loss from the region.”
The team estimated that loss of around 180 km3 of ice from Helheim glacier contributed about 16 mm of the uplift, with about 5 mm accounted for by loss of 310 km3 of ice from Kangerdlugssuaq glacier, and the remainder of the uplift caused by ice volume loss from the ice sheet margin along the south-eastern coast. In total, the researchers estimate a total ice volume loss over five years of roughly 760 km3.
“We all know that melting of ice in Greenland, Alaska, Antarctica etc. causes global sea level rise,” said Khan. “From 1900 to 2000, the sea level has risen about 18 cm. With the recent acceleration of ice mass loss, we expect additional rise of the global sea level.”
The researchers have now started to focus on areas in north Greenland to see if there are any signs of acceleration of ice-mass loss developing there.
The researchers reported their work in Geophysical Research Letters.