Satellite images reveal massive disintegration of Antarctic ice
The Wilkins Ice Shelf had been stable for most of the last century, but began retreating in the 1990s. Researchers believe it was held in place by an ice bridge linking Charcot Island to the Antarctic mainland.
But the 330sq-kilometre bridge lost two large chunks last year and then shattered completely on April 5.
“As a consequence of the collapse, the rifts, which had already featured along the northern ice front, widened and new cracks formed as the ice adjusted,” the ESA said yesterday on its website.
The first icebergs started to break away on Friday, and since then some 700sq km of ice have dropped into the sea, according to the satellite data.
“There is little doubt that these changes are the result of atmospheric warming,” said David Vaughan of the British Antarctic Survey.
“The retreat of Wilkins Ice Shelf is the latest and the largest of its kind,” he said, adding that “eight separate ice shelves along the Antarctic Peninsula have shown signs of retreat over the last few decades”.
The Wilkins Shelf, which is the size of Jamaica, lost 14% of its mass last year, according to scientists who are looking at whether global warming is the cause of its breakup.
Average temperatures in the Antarctic Peninsula have risen by 2.5 Celsius over the past 50 years — higher than the average global rise, according to studies.
Over the next several weeks, scientists estimate the Wilkins Shelf will lose some 3,370sq km — a piece two-thirds the size of Luxembourg.
Angelika Humbert of Germany’s Muenster University Institute of Geophysics said: “We are not sure if a new stable ice front will now form between Latady Island, Petrie Ice Rises and Dorsey Island.”
But even more ice could break off “if the connection to Latady Island is lost”, she said, “though we have no indication that this will happen in the near future”.
Researchers said the quality and frequency of the ESA satellite images have allowed them to analyse the Wilkins Shelf breakup far more effectively than previously.
“For the first time, I think, we can really begin to see the processes that have brought about the demise of the ice shelf,” said Vaughan.
