East Antarctica's massive ice sheet may be more exposed to global warming than previously thought, a new study suggests.
In 2014, scientists were left baffled when they found a huge, 2-mile-wide circle over an Antarctic ice shelf. Some speculated that a meteorite may have caused it. Now, a new study by researchers from Belgium and Netherlands revealed that strong warm winds can erode the ice shelf in the eastern peninsula of Antarctica.
Published in the journal Nature Climate Change, the researchers visited the circle on foot for the first time and they found a deep depression with raised edges. In the center, there were three moulins, which are vertical well-like shafts in the ice, which drains two melt water streams.
They drilled through the ice and found what they called "englacial" lakes, which is water sandwiched between the ice's surface and its base, Washington Post reports. In fact, the researchers discovered 55 lakes on or in the ice shelf.
The research team combined climate models, satellite data and on-site measurements. They concluded that strong winds carrying warm air were blowing away reflective snow, paving way for the rays of the Sun to be absorbed into the ice, rather than bouncing back into space.
These winds, which often blows in one direction over the ice sheet, erode the surface snow, exposing the blue ice underneath. Usually, the erosion is compensated by the formation of fresh snow and ice from above. However, oceans are absorbing excess heat generated by global warming, increasing the global air temperatures by 1 degree Celcius.
"These processes-previously unseen in East Antarctica-indicate that further warming may amplify the risk of ice shelf collapse," Martin Siegert at Imperial College London, who commented on the study, said as reported by Phys.org.
The frightening part of the discovery shows that even though the Antarctic ice sheet is a sold mass of ice, it has vulnerabilities and weaknesses in some of its parts. There is a greater potential of collapse, and when this happens, the glacial ice behind it flows more quickly to the ocean, increasing sea levels.