Washington: A new research has claimed that East Antarctic Ice Sheet could be at a higher risk to the effects of climate change than previously believed.
A team from Durham University`s Department of Geography used declassified spy satellite imagery to create the first long-term record of changes in the terminus of outlet glaciers - where they meet the sea - along 5,400km of the East Antarctic Ice Sheet`s coastline.
The imagery covered almost half a century from 1963 to 2012.
Using measurements from 175 glaciers, they were able to show that the glaciers underwent rapid and synchronised periods of advance and retreat which coincided with cooling and warming.
The researchers said this suggested that large parts of the ice sheet, which reaches thicknesses of more than 4km, could be more susceptible to changes in air temperatures and sea-ice than was originally believed.
The Durham team said there was now an urgent need to understand the vulnerability of the East Antarctic Ice Sheet, which holds the vast majority of the world`s ice and enough to raise global sea levels by over 50m.
The researchers found that despite large fluctuations in terminus positions between glaciers - linked to their size - three significant patterns emerged:
In the 1970s and 80s, temperatures were rising and most glaciers retreated;
During the 1990s, temperatures decreased and most glaciers advanced;
And the 2000s saw temperatures increase and then decrease, leading to a more even mix of retreat and advance.
The findings have been published in the journal Nature.