Sci­en­tists say tril­lion-tonne ice­berg has bro­ken off in Antarc­tica

The Guardian (Charlottetown) - - WORLD -

A vast ice­berg with twice the vol­ume of Lake Erie has bro­ken off from a key float­ing ice shelf in Antarc­tica, sci­en­tists said Wed­nes­day.

The ice­berg broke off from the Larsen C ice shelf, sci­en­tists at the Univer­sity of Swansea in Bri­tain said. The ice­berg is de­scribed as weigh­ing 1 tril­lion tons (1.12 tril­lion U.S. tons).

The process, known as calv­ing, oc­curred in the last few days, when a 5,800-square-kilo­me­tre (2,240-square-mile) sec­tion broke away.

“We have been an­tic­i­pat­ing this event for months, and have been sur­prised how long it took for the rift to break through the fi­nal few kilo­me­tres of ice,” said Adrian Luck­man of Swansea Univer­sity. “We will con­tinue to mon­i­tor both the im­pact of this calv­ing event on the Larsen C Ice Shelf, and the fate of this huge ice­berg.”

It was a nat­u­ral event that wasn’t caused by man-made cli­mate change, said Swansea glaciol­o­gist Martin O’Leary.

None­the­less, “this puts the ice shelf in a very vul­ner­a­ble po­si­tion,” he said in a state­ment.

Sci­en­tists said the lat­est ice­berg break won’t af­fect sea lev­els in the short term.

NASA and Euro­pean Space Agency satel­lites have been mon­i­tor­ing the shelf — of­fer­ing dra­matic pic­tures of the break that height­ened in­ter­est be­yond the sci­en­tific com­mu­nity. The fi­nal break was first re­vealed in a ther­mal in­frared im­age from NASA’s Aqua MODIS satel­lite in­stru­ment.

Sci­en­tists from the U.K.based Antarc­tic project, MIDAS, have been mon­i­tor­ing the rift in Larsen C for years, fol­low­ing ear­lier re­search on the col­lapse of the Larsen A shelf in 1995 and the breakup of the Larsen B shelf in 2002.

The project, which is in­ves­ti­gat­ing the ef­fects of a warm­ing cli­mate through a com­bi­na­tion of field­work, satel­lite ob­ser­va­tion and com­puter sim­u­la­tion, de­scribes the ice­berg as one of the largest ever recorded.

They re­searchers sug­gest the ice­berg is likely to break into frag­ments and say that while some of the ice may stay nearby for decades, parts of it may drift north into warmer waters. But re­searchers say much more study needs to be done to de­ter­mine the cause.

“At this point it would be pre­ma­ture to say that this was caused by global warm­ing,” said Anna Hogg of the Cen­tre for Po­lar Ob­ser­va­tion and Mod­el­ling at the Univer­sity of Leeds.

AP PHOTO

This Nov. 10, 2016 aerial photo re­leased by NASA, shows a rift in the Antarc­tic Penin­sula’s Larsen C ice shelf. A vast ice­berg with twice the vol­ume of Lake Erie has bro­ken off from a key float­ing ice shelf in Antarc­tica, sci­en­tists said Wed­nes­day.

Newspapers in English

Newspapers from Canada

© PressReader. All rights reserved.