The B31 iceberg, six times larger than the borough of Manhattan, is large enough to warrant special attention from NASA.
In November 2013, the giant iceberg broke free from the Pine Island Glacier in Antarctica. This is a fairly unusual place to observe such pieces breaking free from the frozen continent. The ice shelf at the glacier has been moving about two-and-a-half miles per year. The area has been closely monitored by researchers who believe global warming may be leading to retreat of ice at the landmark.
The floating frozen mountain is roughly 20 miles in length by 12.5 miles wide, giving it a total area of 255 square miles, about half the size of Greater London. Ice composing the floating island is one-third of a mile thick.
After breaking off the glacier, B31 may have partly grounded on the floor of Pine Island Bay, as the massive object rocked from side-to-side.
"The iceberg is now well out of Pine Island Bay and will soon join the more general flow in the Southern Ocean," Grant Bigg of the University of Sheffield said.
No shipping lanes are currently threatened by B31, although the space agency is keeping a careful eye on the island of ice. Federal agencies routinely monitor dozens of icebergs, partly due to difficulties predicting behavior of the ice islands.
"It is hard to predict with certainty where and when these things will drift. Icebergs move pretty slowly, and watching this iceberg will be a waiting game," Kelly Brunt, NASA glaciologist, said.
In the open ocean, it becomes even more difficult to predict the future path of the iceberg then in shallower waters.
"[The iceberg] could take a very long time to melt, well over a year or even longer," Bethan Davies, from the University of Reading, told the press.
The research scientist said she believes B31 could drift to populated shipping lanes, possibly posing a hazard in coming months. As summer approaches in the Northern Hemisphere, winter is coming to Antarctica.
Depending on conditions, B31 could either go around the frozen continent heading west, if it is caught in the coastal counter-current, or eastward if the iceberg enters the wider circumpolar current.
The largest iceberg ever measured, B15, broke off the Ross Ice Shelf of Antarctica in March 2000. At one time, it covered 4,250 miles, roughly the size of the island nation of Jamaica. Fourteen years after it cleaved off the ice shelf, pieces of it are still floating in the waters of Antarctica.
