An iceberg about twice the size of New York City will break off Antarctica’s Brunt Ice Shelf into the Atlantic Ocean, NASA said Sunday.
Satellite images posted by the NASA Earth Observatory show two cracks. The crack along the top of the shelf, dubbed, “The Halloween Crack,” was first observed in October 2016. It has since pushed its way eastward. The greater concern is the rift moving north from the bottom of the Brunt Ice Shelf since the crack recently started accelerating as fast as 2.5 miles per year.
NASA says the break poses an uncertain future for “scientific infrastructure and a human presence on the shelf that was first established in 1955.
The British Antarctic Survey is stationed on the Brunt Ice Shelf at the Halley VIa Research Station.
About 30 science, technical and operation staff live on the Halley Research Station, which was established in 1956 – scientists studying the Earth’s atmosphere in 1985 discovered the ozone hole.
The station has been moved several times over the years due to the threat of chasms and cracks in the ice.
"We don't have a clear picture of what drives the shelf's periods of advance and retreat through calving," said NASA/UMBC glaciologist Chris Shuman. "The likely future loss of the ice on the other side of the Halloween Crack suggests that more instability is possible, with associated risk to Halley VIa."