New NASA satellite imagery released February 21 points to a startling, sudden warming event near the tip of the Antarctic Peninsula, the part of the continent closest to South America, where high barometric pressure and changes in wind patterns drove dramatic melting on Eagle Island.
The island lost four inches (10 centimetres) of snow cover, about 20% of its annual snow accumulation, in a single shot, the Washington Post reports, citing Nichols College glaciologist Mauri Pelto.
“During the warming event, about 0.9 square miles (2.33 square kilometres) of snow cover became saturated with meltwater, which shows up on the satellite images as blue-covered melt ponds,” the Post reports. “According to climate models, Eagle Island experienced peak melt of one inch on February 6.”
Satellite images also show widespread surface melting nearby on Boydell Glacier, Pelto said.
“I haven’t seen melt ponds develop this quickly in Antarctica,” he told the Post. “You see these kinds of melt events in Alaska and Greenland, but not usually in Antarctica.”
Pelto added that this type of rapid melting generally results from prolonged periods of above-freezing temperatures which have been more common in Antarctica in recent years. “If you think about this one event in February, it isn’t that significant,” he said. “It’s more significant that these events are coming more frequently.”