An iceberg about six times the size of Manhattan, known as B31, separated from Antarctica’s Pine Island Glacier on November 13, 2013, and is now being monitored by scientists. NASA geologist Kelly Brunt said the iceberg covers about 255 square miles (660 square km) and is up to a third of a mile (500 meters) thick.
Although the iceberg’s present location is not in an area heavily navigated by ships, Brunt indicates, “It’s one that’s large enough that it warrants monitoring.”
“There’s not a lot of shipping traffic down there. We’re not particularly concerned about shipping lanes. We know where all the big ones are. … It’s like a large sheet cake floating through the Southern Ocean,” Brunt added.
B31 is of particular interest to scientists not only because of its size but also because it originated from an unexpected location.
The glacial crack creating B31 was first discovered in 2011. Pine Island Glacier has been closely studied over the past two decades because it has been thinning and draining rapidly – perhaps an important contributor to sea level rise, according to scientists.
“We are doing some research on local ocean currents to try to explain the motion properly. It has been surprising how there have been periods of almost no motion, interspersed with rapid flow,” said iceberg researcher Grant Bigg of the University of Sheffield in England.
“There were a couple of occasions early on when there might have been partial grounding or collisions with the sea floor, as B31 bounced from one side of the bay to the other,” Bigg said.
Hopefully there will be no collisions with a ship before B31 is swept up in the swift currents of the Southern Ocean.