An iceberg the size of the city of Norfolk in Virginia, has broken off the Brunt Ice Shelf in the British Antarctic.
The announcement was made by the research center, British Antarctic Survey's Halley Research Station. Glaciologists say the 490-square mile glacier was expected to break free for at least a decade.
“The first indication that a calving event was imminent came in November 2020 when a new chasm – called North Rift – headed towards another large chasm near the Stancomb-Wills Glacier Tongue about 11,000 feet away. North Rift is the third major crack through the ice shelf to become active in the last decade.
“During January, this rift pushed northeast at up to 1 km per day, cutting through the 150-m thick floating ice shelf. The iceberg was formed when the crack widened several 328 feet in a few hours on the morning of February 26, releasing it from the rest of the floating ice shelf,” the British Antarctic Survey's Halley Research Station writes.
The BAS research station is currently closed for the Antarctic winter and will likely be unaffected by the calving event, scientists said. The BAS said the station was moved further inland in 2016 to "avoid the paths" of two chasms named "Chasm 1," which formed in 2012, and the "Halloween Crack," which formed in 2016. Neither have grown in the past 18 months.
“Over coming weeks or months, the iceberg may move away; or it could run aground and remain close to Brunt Ice Shelf. Halley Station is located inland of all the active chasms, on the part of the ice shelf that remains connected to the continent. Our network of GPS instruments will give us early warning if the calving of this iceberg causes changes in the ice around our station.”