The world's largest ice sheet may be more vulnerable to climate change than previously believed, according to declassified spy satellite imagery of the East Antarctic Ice Sheet's coastline.
Due to its intensely cold temperatures, which are capable of dropping below negative 30 degrees Celsius at the coast and even colder farther inland, East Antarctica has long been considered relatively immune to global warming. However, a new study based on the newly-revealed information suggests this may not be the case.
A team of scientists from Durham University used the data gathered between 1963 and 2012 to map the changes in some 175 glaciers located in the region. In doing so, they found a distinct correlation between phases of rapid and synchronized advancement and retreat in the ice sheet's Pacific Coast and both cooling and warming periods.
According to co-author Chris Stokes of the school's geography department, these changes came as "a big surprise" to the researchers, but that "it made perfect sense when we looked at the climate and sea-ice data."
"When it was warm and the sea-ice decreased, most glaciers retreated, but when it was cooler and the sea ice increased, the glaciers advanced," he said in a statement.
In particular, the researchers detected a glacial retreat during the 1970s and 1980s, which was paired with an increase in temperatures. Then, as temperatures dropped during the 1990s, the glaciers advanced. This was followed by a mix of retreat and advance during the 2000s as temperatures increased and then decreased.
Based on these findings, the researchers argue that more attention should be paid to the region that, if it were to melt completely, would single-handedly raise global sea levels by over 50 meters.
"If the climate is going to warm in the future," Stokes said, "our study shows that large parts of the margins of the East Antarctic Ice Sheet are vulnerable to the kinds of changes that are worrying us in Greenland and West Antarctica -- acceleration, thinning and retreat."