The largest iceberg on file, B15, broke off from the Ross Ice Shelf in March 2000 measuring greater than 4,200 sq. miles (11,000 sq. kilometers). Despite being greater than twice the scale of A76, Dr. Shuman mentioned, B15 didn’t destabilize the Ross Ice Shelf. B15 has since fractured into a number of icebergs, all however certainly one of which have melted away.
According to Dr. Shuman, the final vital calving occasion on the Ronne shelf was in May 2000.
By finding out the brand new iceberg, researchers hope to higher perceive the general state of Antarctica’s ice cabinets, mentioned David Long, who runs the Antarctic Iceberg Tracking Database at Brigham Young University.
“Understanding when the ice sheets calve helps us understand whether some of these other more unstable ice sheets could break up or disintegrate,” he mentioned. “And that would be important because as these more unstable ice sheets break up they can release the flow of glaciers that are held in place by the ice shelves.”
While ice cabinets are floating on the water, the glaciers behind them are on land. So if they’re launched into the ocean and soften, that may add to sea ranges, he mentioned.
The National Ice Center names and tracks Antarctic icebergs which might be a minimum of 10 nautical miles lengthy or 20 sq. nautical miles giant. The middle, which is operated by the Navy, the Coast Guard and the National Oceanic and Atmospheric Administration, is at present monitoring 42 named icebergs.
The query with A76 is what is going to occur subsequent.
An iceberg about 100 miles lengthy and 30 miles huge that had damaged off from the Antarctic Peninsula in 2017 raised alarm in November when it appeared to be on a collision course with the British island territory of South Georgia. That iceberg, A68a, ended up grounding off the island’s coast. If A76 hits the same present, it might attain the Antarctic Peninsula inside months and will intrude with delivery lanes there, mentioned Christopher Readinger, the Ice Center’s Antarctica crew lead.
As A76 makes its journey, Dr. Jackson mentioned, climatologists can be watching intently — even when a lot of the general public isn’t. Dr. Jackson cited A68a, the iceberg that briefly threatened South Georgia.