Further evidence of serious Antarctic ice melting
The Independent reports, 21st May 2015: A sudden and massive melting of glaciers in a part of the Antarctic that was thought to be relatively stable has been detected by satellites monitoring the polar ice sheet, scientists have said.
Many glaciers in the Southern Antarctic Peninsula have become unstable since 2009, releasing vast amounts of ice into the sea equivalent to about 56bn tonnes of meltwater each year, the researchers said.
Multiple glaciers along a stretch of coastline 750km long have suddenly and consistently started to shed ice into the ocean at a constant rate of 60 cubic km or 55 trillion litres of water each year, they report in the journal Science.
This would make this region of Antarctica, which until 2009 showed no signs of melting, the second largest contributor of sea level rise in Antarctica, with no indication of it waning, they said.
“To date, the glaciers added roughly 300 cubic km of water to the ocean. That’s the equivalent of the volume of nearly 350,000 Empire State Buildings combined,” said Bert Wouters of the University of Bristol, the lead author of the study.
“The fact that so many glaciers in such a large region suddenly started to lose ice came as a surprise to us. It shows a very fast response of the ice sheet. In just a few years the dynamic regime completely shifted,” Dr Wouters said.
The scientists believe that warmer ocean currents are the cause of the melting ice. Westerly winds in the region have increased in strength as a result of global warming and ozone depletion, which has contributed to the ice shelves on the coast to be eaten away, they said.
The ice shelves of Antarctica, where land ice sticks out over the sea, are seen as crucial to holding back the massive land-based ice sheets behind them. The loss of ice shelves is thought to increase the risk of massive parts of the Antarctic ice sheet slipping towards the ocean, where they can contribute to global sea-level rise.
Source: The Independent, 21st May 2015. For the full text, see www.independent.co.uk/environment/climate-change/glaciers-in-part-of-antarctic-thought-to-be-stable-suddenly-melting-at-a-massive-rate-say-scientists-10268053.html
