Giant iceberg breaks free from Antarctic glacier
Friday 26 February 2010
An iceberg the size of Luxembourg has broken off from a glacier in Antarctica after being rammed by another giant iceberg, scientists said on Friday, in an event that could affect ocean circulation patterns.
The 2,500 sq km (965 sq mile) iceberg broke off earlier this month from the Mertz Glacier's 160 km (100 miles) floating tongue of ice that sticks out into the Southern Ocean.
The collision has since halved the size of the tongue that drains ice from the vast East Antarctic ice sheet.
"The calving itself hasn't been directly linked to climate change but it is related to the natural processes occurring on the ice sheet," said Rob Massom, a senior scientist at the Australian Antarctic Division and the Antarctic Climate and Ecosystems Cooperative Research Centre in Hobart, Tasmania.
Both organisations, along with French scientists, have been studying existing giant cracks in the ice tongue and monitored the bumper-car-like collision by the second iceberg, B-9B.
This 97 km long slab of ice is a remnant of an iceberg of more than 5,000 sq km that broke off, or calved, in 1987, making it one of the largest icebergs ever recorded in Antarctica.
The Mertz glacier iceberg is among the largest recorded for several years. In 2002, a iceberg about 200 km long broke off from Antarctica's Ross Ice Shelf. In 2007, a iceberg roughly the size of Singapore broke off from the Pine Island Glacier in West Antarctica.
Massom said the shearing off of the ice tongue and the presence of the Mertz and B-9B icebergs could affect global ocean circulation.
The area is an important zone for the creation of dense, salty water that is a key driver of global ocean circulation. This is produced in part through the rapid production of sea ice that is continually blown to the west.
"Removal of this tongue of floating ice would reduce the size of that area of open water, which would slow down the rate of salinity input into the ocean and it could slow down this rate of Antarctic bottom water formation," he said.
He said there was a risk both icebergs would become grounded on banks or shoals in the area, disrupting the creation of the dense, salty water and the amount that sinks to the bottom of the ocean, he said.
Oceans act like a giant flywheel for the planet's climate by shifting heat around the globe via myriad currents above and below the surface.
Greenland’s dark snow may start global warming ‘feedback loop’
The ugliest animals on earth: Blobfish, axolotl and proboscis monkey battle it out to be named least attractive beast
India's hidden climate change catastrophe
Animal Extinction - the greatest threat to mankind
Climate change means rate of growth of trees has gone up by 77%
- 1 Hilary Mantel 'should be investigated by police' over Margaret Thatcher assassination story, says Lord Bell
- 2 Stamford Hill council removes 'unacceptable' posters telling women which side of the road to walk down
- 3 Kim Kardashian 'nude pictures' leaked on 4chan weeks after Jennifer Lawrence 'The Fappening' scandal
- 4 Iranian blogger found guilty of insulting Prophet Mohammad on Facebook sentenced to death
- 5 New Tricks: Dennis Waterman to leave the show after a decade of crime-solving
Scottish independence referendum: A nation divided against itself
Scottish referendum results: Cross-party consensus collapses amid Tory-Labour spat on the 'English question'
Scottish independence: David Cameron is becoming the 'George Bush of Britain'
Russia freezes Ukraine into submission: Kiev admits country doesn't have enough fuel for winter
Plebgate MP Andrew Mitchell called officer a 'little s**t', claim court documents 'exposing ex-Chief Whip's 'record of abusing police'
Archbishop of Canterbury admits doubts about existence of God
£70000 - £80000 per annum: Ashdown Group: Group Head of Marketing and Communic...
Negotiable: Randstad Education Manchester: Level 3 Nursery Nurse required for ...
Negotiable: Randstad Education Manchester: L3 Nursery Nurses urgently required...
Negotiable: Randstad Education Manchester: We have a number of schools based S...