Close to 2,240 square-mile (5,800 square kilometers) chunk of ice has broken away
Animated GIF of the growth of the crack in the Larsen C ice shelf, from 2006 to 2017, as recorded by NASA/USGS
A massive iceberg the size of Delaware has broken free from Antarctica and is floating in the sea.
“Put any adjective you like on it: a corker, a whopper — it’s a really large iceberg,” says Anna Hogg, a researcher with the United Kingdom’s Centre for Polar Observation and Modelling at the University of Leeds. Earlier Wednesday, scientists announced that the 6,000-square-kilometer (about 2,300 square miles) iceberg had come loose, after satellites detected it had calved off the Larsen C ice shelf on the Antarctic Peninsula.
“The interesting thing is what happens next, how the remaining ice shelf responds,” said Kelly Brunt, a glaciologist with NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and the University of Maryland in College Park. “Will the ice shelf weaken? Or possibly collapse, like its neighbors Larsen A and B? Will the glaciers behind the ice shelf accelerate and have a direct contribution to sea level rise? Or is this just a normal calving event?”
Dan McGrath, a glaciologist at Colorado State University who has been studying the Larsen C ice shelf since 2008. McGrath said the growth of the crack, given our current understanding, is not directly linked to climate change.
“The Antarctic Peninsula has been one of the fastest warming places on the planet throughout the latter half of the 20th century. This warming has driven really profound environmental changes, including the collapse of Larsen A and B,” McGrath said. “But with the rift on Larsen C, we haven’t made a direct connection with the warming climate. Still, there are definitely mechanisms by which this rift could be linked to climate change, most notably through warmer ocean waters eating away at the base of the shelf.”
The U.S. National Ice Center will monitor the trajectory of the new iceberg, which is likely to be named A-68. The currents around Antarctica generally dictate the path that the icebergs follow. In this case, the new berg is likely to follow a similar path to the icebergs produced by the collapse of Larsen B: north along the coast of the Peninsula, then northeast into the South Atlantic.
Wide view of Larsen C ice shelf and its recently calved iceberg. Darker colors are colder, and brighter colors are warmer, so the rift between the iceberg and the ice shelf appears as a thin line of slightly warmer area. Image from July 12, 2017.