Gigantic iceberg, almost as big as Greater London, breaks off from Antarctic ice shelf

 

A giant iceberg, almost the size of Greater London has broken off from an Antarctic ice shelf, near Britain’s Halley research station, BBC reported. Notably, icebergs are large chunks of ice that break off from glaciers in a process called calving, according to National Geographic.

The massive iceberg, which is nearly 600 square miles (1550 sq km), broke free from the 492ft-thick (150m) Brunt Ice Shelf on Sunday. The iceberg finally calved when the crack known as Chasm-1 fully extended through the ice shelf. However, contrary to speculations, the event is not related to climate change. The British Antarctic Survey (BAS), which monitors the state of the vast floating ice shelf daily at the research station, noted that the calving event was expected and is a ‘part of the natural behavior of the Brunt Ice Shelf’.

‘It is not linked to climate change’, said BAS glaciologist Dominic Hodgson. The BAS also added that the area of the ice shelf where the research station is located currently remains unaffected by the recent calving events. However, the calving of large bergs from a shelf structure can lead to a speed-up in the flow of the ice and also influence the behaviour of other cracks in the area.

This is the second such split in two years. In February 2021, a 1,270 sq km iceberg known as A74 broke away from the 150-metre-thick Brunt Ice Shelf. BAS said that the new iceberg is slightly larger than A74, and is likely to drift in the same direction due to the current. It will be named later by the US National Ice Center. Both these events have taken place a decade after scientists at BAS first detected the growth of vast cracks in the ice. Prior to this latest iceberg and A74, the last major chunk to come off the Brunt was in 1971.

In a press release, Professor Dame Jane Francis, Director of BAS said, ‘Our glaciologists and operations teams have been anticipating this event. Measurements of the ice shelf are carried out multiple times a day using an automated network of high-precision GPS instruments that surround the station. These measures how the ice shelf is deforming and moving, and are compared to satellite images from ESA, NASA and the German satellite TerraSAR-X. All data are sent back to Cambridge for analysis, so we know what is happening even in the Antarctic winter – when there are no staff on the station, it is dark for 24 hours and the temperature falls below minus 50 degrees C’.