Giant iceberg breaks off in Antarctica, ESA: “It’s 5 times bigger than Malta”

The European Space Agency has released the images of the Copernicus Sentinel satellites: “It detached from the Brunt ice shelf, the crack had started to widen in 2012”

It fell away from Brunt Ice Shelf of theAntarctica L‘giant iceberg whose crack had begun to open in 2012. And, according to glaciologists, the detachment would not have occurred due to climate change. To see the detachment were the Sentinel satellites of the European Copernicus program of ESA el‘European Space Agency announced that satellite images confirm that a massive iceberg, about five times the size of Malta, has finally calved off Antarctica’s Brunt Ice Shelf. ESA reported today that the new berg – which according to the British observatory Bas would have detached last Sunday 22 January – is estimated to be about 1,550 square kilometers wide and about 150 meters thick, gave way when the crack, known as Chasm-1, has extended completely northwards, severing the western part of the ice shelf. The crack that caused the iceberg to break off was first detected in 2012 after having been dormant for several decades. After several years in which the mass of ice remained ‘clinging’ to the Brunt shelf, image data from the Copernicus Sentinel missions has now ‘visually confirmed the calving event’, ESA announced.

Glaciologists had been monitoring the giant iceber for years, so much so that the European Space Agency even speaks of ‘birth’ and explains that the timing of the detachment, “although unexpected, had long been anticipated. For years, glaciologists have monitored the numerous cracks and chasms that formed in the thick Brunt Ice Shelf, which borders the coast of Coats Land in Antarctica’s Weddell Sea sector.It was only a matter of time before Chasm 1, which had lain dormant for decades, encountered Halloween Crack, first spotted on Halloween 2016”. ESA points out that the new iceberg is expected to be named A-81 with the smaller northern piece likely identified as A-81A or A-82. Icebergs, ESA explains, are traditionally identified by a capital letter indicating the Antarctic quadrant in which they were originally sighted, followed by a sequential number, then, if the iceberg breaks into smaller pieces, by a letter sequential lowercase. The split was first reported by the Bas-British Antarctic Survey as having occurred on 22 January between 1900 and 2000 UTC during a spring tide. Bas’s Halley VI research station, where glaciologists monitored the behavior of the ice shelf, was unaffected by the calving event. ESA recalls that the research station was relocated in 2017 to a safer location after the ice shelf was deemed unsafe. The station is currently about 20km from the breakline and there are currently 21 people working on the station maintaining the feeders and facilities that keep the science experiences running through the winter.

“The detachment of the iceberg has finally occurred” articulates the researcher and ice expert Mark Drinkwater of the European Space Agency who thus welcomed the news of the detachment of the giant iceberg, 5 times the size of Malta and the event according to the glaciologist Dominic Hodgson of the British Antarctic Survey “is not linked to climate change”. Drinkwater points out in a post on esa.int that “after several years of monitoring the ‘calving’ of the iceberg, the long-awaited separation of the Brunt A81 iceberg has finally occurred”. “The northward propagation of Chasm 1 and Bas’s timely decision to move Halley Base to safer ground were accompanied by what has been perhaps the most detailed and longest-running examination of the events leading up to the natural calving from an Antarctic ice shelf,” explains the scientist. “Thanks to Copernicus, combined with in situ and aerial measurements made by the British Antarctic Survey, the safety of Halley base has been preserved. In the meantime – continues Drinkwater – the combination of Sentinel-2 summer images and the availability of monitoring throughout year and winter by Sentinel-1 radar has placed the pattern of deformation and propagation of an ice shelf fracture under the worldwide public microscope.”

For Dominic Hodgson, Bas glaciologist, “this ‘calving’ was expected and is part of the natural behavior of the Brunt ice shelf. It is not related to climate change. Our scientific and operational teams continue to monitor the ice shelf in real time to ensure it is safe and to maintain the delivery of the science we undertake at Halley 0ESA and Bas scientists report that ‘iceberg calving from an ice shelf is followed by an adjustment of ice flow into the ice shelf “. “If Brunt now experiences an acceleration, it could affect the behavior of other cracks in the area” they add finally.



Source-www.adnkronos.com