One of the biggest icebergs ever recorded, a trillion-ton behemoth more than seven times the size of New York City, has severed of Antarctica, activating difference among researchers about whether global warming is to blame.
The occasion, caught by satellite, happened at some point in the past few days when the giant chunk snapped off an ice shelf.
While such “calving” of icy masses is not bizarre, this is a particularly huge one. It covers a range of around 2,300 square miles (6,000 square kilometers), more than double the extent of Luxembourg. Its volume is twice that of Lake Erie, as indicated by Project MIDAS, a research group based in Britain.
It broke loose from the Larsen C ice shelf, which researchers had been observing for a considerable length of time as they watched a split develop more than 120 miles (200 kilometers) in length.
Scientists say global warming has caused a thinning of such shelves. However, they contrast on whether the most recent occasion can be faulted for climate change.
The iceberg is considered unlikely to pose any threat to shipping. Furthermore, since the ice was at that point gliding, the separation won’t raise sea levels in the short term, the project said in a statement.
But it removed more than 10 percent of the ice shelf, and if that, in the long run, rushes the stream of ice sheets behind it into the water, there could be a “very modest” ascent in sea level, the project said.
Two other Antarctic ice shelves, farther north on the Antarctic Peninsula, collapsed in 1995 and 2002. That accelerated the slide of ice sheets, which added to ocean level ascent, David Vaughan, chief of science at the British Antarctic Survey, said in a statement.
“Our glaciologists will now be watching closely to see whether the remaining Larsen C ice shelf becomes less stable than before the iceberg broke free,” he said.
Eric Rignot, a glaciologist at the University of California, Irvine, said the severing of the chunk of ice “is part of a major long-term loss of the ice shelves in the peninsula, progressing southbound and resulting from climate warming.”
But Swansea University glaciologist Martin O’Leary, a member of the MIDAS project, called it “a natural event, and we’re not aware of any link to human-induced climate change.”
Also, a spokeswoman for the British Antarctic Survey said there’s not enough information to state whether the calving is an impact of environmental change, though there’s good evidence global warming has caused thinning of the ice shelf.
On any danger to navigation, scientists said the iceberg would probably break up, and its pieces will hover Antarctica for quite a long time or decades rather than drifting northward into shipping lanes.