As soon as an iceberg is born it starts to die. Waves chip away at its edges, air thaws it from above, and water melts it from below. Scientists recently chronicled such death throes for one of the world’s largest-known icebergs.
In July 2017, Iceberg A-68 broke from the Larsen C Ice Shelf, along the east coast of the Antarctic Peninsula. At the time, it was the largest iceberg in the world and the sixth-largest berg in three decades of records. It measured nearly 5,800 square kilometers (2,200 square miles), or about the size of Delaware. In other words, A-68 had a lot to lose. Across three and a half years, the berg broke apart and melted, leaving its mark on the ocean environment, especially near the remote island of South Georgia.
“Icebergs are a source of cold fresh water and nutrients in the Southern Ocean,” said Anne Braakmann-Folgmann, a doctoral candidate at the University of Leeds. “However, where and how much of this is released is not very well studied and not included in ocean models yet, especially for the largest icebergs.”
Braakmann-Folgmann and colleagues set out to chart the journey of A-68A. (The new name was given to the main berg after a few small pieces broke off.) The researchers used satellite data to document changes in the iceberg’s thickness, area, volume, and mass from the time it broke from the ice shelf in July 2017 until it started to quickly disintegrate in January 2021.
Read more at: NASA Earth Observatory
Photo Credit: NASA Earth Observatory