Last week, a city-state sized chunk of ice broke off of Pine Island Glacier (PIG), sending iceberg B-31 into a bay off West Antarctica. Though the formation of the 700 square-kilometer iceberg could be a purely natural event — the result of a floating ice tongue growing too long and losing its balance on the sea — some scientists suspect that changes in Pine Island Glacier are due to changing conditions below.
Five years ago this week, another block of ice broke off of the Antarctic Peninsula (radar image above from November 26, 2008). The seaward edge of Wilkins Ice Shelf spent much of 2008 breaking loose from the continent. Unlike PIG, Wilkins shattered and splintered into much smaller bits. And in that case, few doubted that global warming — or at least warming of the Antarctic Peninsula — played a major role.
NASA satellites are still tracking the last week’s PIG offspring. Check out these images from: