Scientists have discovered that the ice shelves of South Antarctica, located in the Bellingshausen sea, are in rapid melt. This new study follows reports that the remnants of Larsen B should disintegrate within a few years, that a 17 mile crack has been spotted on Larsen C and that Larsen C is at risk of collapse. The discovery that the southern ice shelves are in rapid melt is new.
Phys.org reports:
Using measurements of the elevation of the Antarctic ice sheet made by a suite of satellites, the researchers found that the Southern Antarctic Peninsula showed no signs of change up to 2009. Around 2009, multiple glaciers along a vast coastal expanse, measuring some 750km in length, suddenly started to shed ice into the ocean at a nearly constant rate of 60 cubic km, or about 55 trillion litres of water, each year.
This makes the region the second largest contributor to sea level rise in Antarctica and the ice loss shows no sign of waning.
The
Christian Science Monitor expands on the story.
As Antarctica’s ice shelves collapse, the glaciers they buttress will contribute to sea level rise. Currently, the glaciers in the study, which lie along 500 miles of the southern Antarctic Peninsula coast, are losing some 56 billion tons of ice a year to the ocean, according to the new study.
The losses began suddenly in 2009 and come in addition to losses from the West Antarctic Ice Sheet, which is shedding 80 billion to 110 billion tons of ice a year, according to the study.
Some losses from nearby ice shelves have been underway for decades. But the seemingly abrupt onset of significant ice losses along the southern coast of the Antarctic Peninsula is an eye-opener, suggests Dr. Gardner of JPL.
Recent studies have shown that Antarctica's two continental ice sheets are more sensitive to changes in ocean and air temperatures than previously thought, he notes. But as relatively warm water from deep reaches of the Southern Ocean moved onto the continental shelf, the thinning sped up, melting the ice shelves from underneath, the researchers of the new study concluded.