Two of the larger fragments were named A-68E and A-68F. On 22 December 2020, images from ESA's Sentinel-1 radar satellite showed that A-68A had experienced a major break-up.
#Antarctica iceberg breaking off 2017 free#
The new free floating iceberg has been designated A-68D. to either anchor in the shallow waters around the island or move past it in the coming days." On this date it was also reported that a corner had been knocked off A-68A, most likely due to impact with the seabed. National Geographic reported that "cientists expect the iceberg. Īs of 17 December 2020, a part of the iceberg was just 50 km (31 mi) from South Georgia, but the concern seemed to have lessened. The RAF conducted reconnaissance flights over the iceberg on 18 November and 5 December 2020. On 9 December 2020, the Royal Air Force released video footage of A-68A, 150 km off South Georgia. A spokesman from the British Antarctic Survey stated that the iceberg could become stuck for a number of years, causing disruption to wildlife and the local fishing industry. On 4 November 2020, it was reported that A-68A was approaching South Georgia Island and that there was a strong possibility that the iceberg might run aground on the shallower continental shelf near the island, posing a grave threat to local penguins and seals. mi.) broke off the iceberg and was named A-68C. On 23 April 2020, a chunk measuring about 175 sq. On 6 February 2020, A-68A began moving into open waters. In 2018 or 2019, a large chunk almost 14 km × 8 km ( 9 miles × 5 miles) broke off and was named A-68B, with the mother iceberg now being A-68A. During 2018, A-68 continued to drift northwards. Ī British expedition on RRS James Clark Ross intended to sample the marine life at the A-68 cleavage line in March 2018, but had to turn back due to thick sea ice. The gap was approximately five kilometers (3.1 miles) wide and contained a thin layer of loose, floating ice and a cluster of more than 11 'smaller' bergs, one much larger than the others. Post November 2017, satellite images showed that A-68 was slowly drifting northward, with a widening gap to the main shelf. Scientists are looking into the possibility of the ice shelf collapsing as a result of the split with A-68, or whether the iceberg was the "cork" for Larsen C that allows ice to flow more freely into the sea, thereby contributing to rising sea levels. Satellite images from the ESA and EU's Copernicus Program show that as the iceberg moved, it was gradually shrinking and splintering, forming more icebergs in the process. Scientists assess that A-68 "didn't just break through in one clean shot, it formed a lace-network of cracks first." The resulting iceberg was around 175 km long and 50 km wide, 5,800 km² in area, 200 m thick and weighed an estimated one trillion tonnes.
#Antarctica iceberg breaking off 2017 crack#
Scientists found the crack beginning to form in November 2016. On 30 January 2021, Iceberg A-68A broke into other icebergs called A-68H, A-68I, A-68J, A-68K, A-68L, A-68M.Ī-68 was part of Larsen C, a section of the Larsen Ice Shelf. The larger child icebergs were designated in order of birthing, as A-68B, A-68C, A-68D, A-68E, A-68F, and in January 2021, splitting almost in half to birth A-68G. It broke into parts with the mother berg dubbed A-68A. The name "A-68" was assigned by the US National Ice Center. Historical data shows that many icebergs that break off from the Antarctic Peninsula reach South Georgia and the South Sandwich Islands.
The calving of A-68 reduced the overall size of the Larsen C shelf by 12 percent. With a surface area of 5,800 square kilometres (2,200 sq mi), twice the size of Luxembourg, over a quarter the size of Wales, and larger than Delaware, it was one of the largest recorded icebergs, the largest being B-15 which measured 11,000 square kilometres (4,200 sq mi) before breaking up. By 16 April 2021, no significant fragments remained. Iceberg A-68 was a giant tabular iceberg adrift in the South Atlantic, having calved from Antarctica's Larsen C ice shelf in July 2017. The drift of Iceberg A-68A from 1 May 2018 to 26 August 2018
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