The largest iceberg of all time, B15, broke off the Ross Ice Shelf in March 2000 covering more than 11,000 square kilometers. Although B15 is more than twice the size of A76, B15 did not destabilize the Ross Ice Shelf. B15 has since broken into several icebergs, all but one of which have melted away.
According to Dr. Shuman was the last major calving event on the Ronne shelf in May 2000.
By studying the new iceberg, researchers hope to better understand the overall condition of Antarctica’s ice shelves, said David Long, who runs the Antarctic Iceberg Tracking Database at Brigham Young University.
“If we understand when the ice sheets calve, we can better understand whether some of these other more unstable ice sheets can crack or crumble,” he said. “And that would be important because when these more unstable ice sheets break, they can free the flow of glaciers that are held in place by the ice shelves.”
While ice shelves float on the water, the glaciers behind are on land. So if they got into the ocean and melted, it would raise the sea level, he said.
The National Ice Center names and tracks icebergs in Antarctica that are at least 10 nautical miles long or 20 square miles large. Operated by the Navy, the Coast Guard, and the National Oceanic and Atmospheric Administration, the center is currently tracking 42 named icebergs.
The question with A76 is what will happen next.
An iceberg approximately 100 miles long and 30 miles wide that broke off the Antarctic Peninsula in 2017 set off the alarm in November when it appeared to be on a collision course with the British island of South Georgia. This iceberg, A68a, landed off the coast of the island. If the A76 encounters a similar current, it could reach the Antarctic Peninsula within a few months and disrupt shipping routes there, said Christopher Readinger, team leader of the Antarctic team at the ice center.
On the way of the A76, says Dr. Jackson, climatologists will look closely – even if much of the public doesn’t. Dr. Jackson cited A68a, the iceberg that briefly threatened South Georgia.
