A satellite image from the European Space Agency captures what it says is the first documented instance of an Antarctic ice shelf breaking apart in winter.
The Wilkins Ice Shelf, located at the base of the Antarctic Peninsula, in the western half of the continent, has been retreating since the 1970s and
in February lost about 400 square kilometers (154 square miles) in a summer breakup. The most recent breakup, in late May and early June, has now nearly severed the shelf’s connection between two islands. Ice shelves usually break up in summer, as warm temperatures create large melt ponds on the shelf’s surface. Meltwater then seeps into the shelf, fracturing it. The northern third of the western Antarctic Peninsula is warming faster than any place on earth, and its ice sheets have been weakening and, in some cases, breaking up, as air and sea temperatures rise. The ice shelves are plates of ice that flow off land-based ice sheets and float atop the sea. The loss of ice shelves does not raise sea level, but their disappearance often leads to glaciers flowing much more rapidly into the sea, which does increase sea level. The Wilkins Ice Shelf is one of Antarctica’s smallest, measuring 129 km by 96 km (80 miles by 60 miles) before this year’s break-up.
European Space Agency