London: Parts of Greenland’s ice sheet are less vulnerable to climate warming than was previously thought, a new analysis of satellite images by an international research team reveals.
The new study, published in the journal Nature, showed that despite dramatic increase in ice melt across Greenland in recent years, the speed of ice movement in some areas has slowed down rather than accelerated.
“We need to understand these ice-climate interactions better in order to be able to make more reliable global sea-level predictions,” said professor Edward Hanna from University of Sheffield.
The team of scientists used satellite data to track the shift of ice features such as crevasses in an 8000 sq kms area of Greenland over three decades.
They found that despite a 50 percent rise in meltwater from the ice surface in recent years, overall movement in the past 10 years was slower than in previous decades.
The study showed this was caused by large amounts of meltwater produced in summer producing channels at the base of the ice sheet, which drain away water efficiently, slowing the glacier’s movement the subsequent winter.
The finding will help scientists improve predictions of how quickly Greenland’s ice will be lost in a warming climate.
“It is clearly not always a simple case of more ice melt resulting in faster-flowing ice, as was originally thought by some to be the case,” Hanna added.
Till recently, experts thought that the increased volumes of meltwater from Greenland’s ice in response to climate warming would speed up the motion of all parts of the ice sheet by helping the ice slide more rapidly.