An iceberg twice the size of New York City has broken off from the 500-foot-thick Brunt Ice Shelf in Antarctica. The 600-square-mile iceberg broke free from Antarctica between 2:00 and 3:00 p.m. ET on Sunday, January 22.
The iceberg breaking away, a phenomenon called "calving," occurred after years of fissures naturally forming on the ice sheet. The ultimate blow was delivered when a fracture known as Chasm-1 completely burst through the whole sheet of ice.
Calving of Iceberg Is Unrelated to Climate Change
According to The Washington Post, scientists discovered the fresh development in Chasm-1 after finding a long-thought-dormant rift in the ice shelf. Since then, scientists have been keeping a tight eye on Chasm-1, anticipating a future rupture.
A news statement from the British Antarctic Survey (BAS), which recorded photographs of the occurrence, reports that the iceberg calved when fissures that had naturally developed over the previous years stretched across the entire ice shelf and caused the new iceberg to break free.
BAS glaciologist Dominic Hodgson said that scientists have been expecting this calving event and are part of the natural behavior of the Brunt Ice Shelf, which means it is not linked to climate change.
Although, the calving event comes amid the record-low sea ice in Antarctica where it is summer. The National Snow and Ice Data Center reported earlier this month that the decline in Antarctic sea ice has been unusually rapid this year despite it being always steep during this period. More so, the Antarctic sea ice extent is at its lowest in the 45-year satellite record.
Researchers said that the low sea ice has been caused in part by a wide band of warmer-than-normal air temperatures, which reached 2 degrees Celsius above average across the Ross Sea in November and December. They also noted that strong winds exacerbated the loss of sea ice.
Recent measurements reveal that the sea ice has not returned, implying that the continent may complete the summer with a new record for the second year in succession. Antarctica has experienced a roller coaster sea ice extent in the past decades, unlike the Arctic ice which is affected by climate change.
Glaciologist Ted Scambos noted that although there is a link between Antarctica and the general warming trend, it is still different from the mountain glaciers and the Arctic. Satellite data shows that Antarctica still produces record-high sea ice as recently as 2014 and 2015 even though it dropped in 2016 and stayed lower than average since.
Brunt Ice Shelf in a Period of Instability
The Brunt Ice Shelf in Antarctica is one of the best-studied ice shelves in the continent and lately, it has been undergoing significant alterations, as per the United States Geological Survey (USGS).
While calving is a natural component of an ice shelf's lifecycle, recent rifting and iceberg calving may indicate that the Brunt Ice Shelf is in an unstable state. It might possibly foretell the fate of other ice shelves in the region.
For almost five decades, Landsat satellites have monitored the ice sheet. A calving event in 1971 decreased its size. Brunt's initial Landsat observations came during the Antarctic summer of 1972-1973, right before the first Landsat was deployed in 1972. Landsat 9 has now joined Landsat 8 in monitoring the developing rifts on the ice shelf.
RELATED ARTICLE: Florida-Sized Doomsday Glacier in Antarctica Is About to Collapse; What Happens Next?
Check out more news and information on Antarctica in Science Times.
