NASA satellite images in late May showed A-76A, an iceberg twice the size of Los Angeles, breaking into pieces near South Georgia Island.
Fragments of the world's largest iceberg A-76A, captured by NASA's Terra satellite on May 24. Photo: NASA Earth Observatory/MODIS/Wanmei Liang
A-76A is the largest remaining piece of A-76, an iceberg measuring about 4,320 square kilometers, 170 kilometers long and 25 kilometers wide, that broke off from the Ronne Ice Shelf, Antarctica, in May 2021. By October 2022, satellite imagery showed that A-76A, then about 135 kilometers long and 26 kilometers wide, had entered the "Drake Passage" sea area, where icebergs are often swept away from Antarctica by strong ocean currents.
On May 24, NASA’s Terra satellite captured new images of six pieces of A-76A drifting away from each other near South Georgia Island in the Scotia Sea, meaning the giant iceberg broke up a few days ago, according to NASA’s Earth Observatory. The pieces are about 2,415 kilometers (1,500 miles) from where A-76 broke away from Antarctica in 2021.
"It's impressive that it's come this far in just about two years. It shows how powerful the currents are in this part of the Southern Ocean," said Christopher Shuman, a glaciologist at the University of Maryland and NASA's Goddard Space Flight Center.
The world’s previous largest iceberg, A-68A, also broke up near South Georgia Island in December 2020 after drifting through the Drake Passage. A-76A did not directly collide with South Georgia, but it could still affect nearby marine ecosystems. By mid-2021, when A-68A had completely melted, scientists estimate it would have dumped about 900 million tons of freshwater into the ocean, much of it near South Georgia. A-76A is also likely to release large amounts of freshwater into the surrounding area, affecting marine food webs.
Mark Belchier, director of Fisheries and Environment for South Georgia and the South Sandwich Islands, warned that new icebergs would continue to break off and could become a major concern for vessels operating in the area.
Thu Thao (According to Live Science )
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