A massive iceberg, spanning 380 square kilometers, separated from Antarctica’s Brunt Ice Shelf last week. This marks the region’s third major calving event in four years, according to a European Space Agency (ESA) report dated May 23.
Previous calving events
The first major calving was reported in 2021 when iceberg A-74 broke off, followed by the even larger A-81 in 2023. The recent separation of this new iceberg, now identified as A-83, was observed by ESA’s Copernicus Sentinel-1 and NASA’s Landsat 8 satellites.
Causes of the May 20 calving
The May 20 calving event was triggered by the prolonged weakening of ice at the McDonald Ice Rumples and the eastward extension of the ‘Halloween Crack.’ “This calving event results from a prolonged weakening of the ice at the McDonald Ice Rumples and progressive eastward extension of the so-called ‘Halloween Crack’ into the ice shelf,” the report stated.
Satellite monitoring of ice shelves enables scientists to observe the impacts of climate change in remote regions like Antarctica. The routine surveillance helps track changes and predict future events.
Iceberg identified as A-83
The US National Ice Center officially designated the new iceberg as A-83. Antarctic icebergs are named based on the quadrant of their origin, followed by a sequential number, and, if necessary, a sequential letter if the iceberg breaks further.
The British Antarctic Survey’s Halley VI Research Station, situated on the Brunt Ice Shelf, remains safe. The station was moved to the Caird Coast in 2017 due to the instability of the outer ice shelf.
