Warning over melting glacier the size of Britain ‘which could trigger 6ft sea level rise'

The Thwaites Glacier in Antarctica is seen in this undated NASA image. Vast glaciers in West Antarctica seem to be locked in an irreversible thaw linked to global warming that may push up sea levels for centuries, scientists said on May 12, 2014. Six glaciers including the Thwaites Glacier, eaten away from below by a warming of sea waters around the frozen continent, were flowing fast into the Amundsen Sea, according to the report based partly on satellite radar measurements from 1992 to 2011. REUTERS/NASA/Handout via Reuters (ANTARCTICA - Tags: ENVIRONMENT SCIENCE TECHNOLOGY) 
The Thwaites Glacier in Antarctica in an image from NASA (Reuters) (NASA NASA / Reuters)

An environmental expert has offered a chilling warming of what might happen if an Antarctic glacier the size of Great Britain melts.

Research published in December suggested that the Thwaites glacier may be becoming unstable - and could collapse within 10 years.

On its own, the collapse could raise sea levels by 65cm - but the knock-on effects could be catastrophic, a researcher has warned.

The Thwaites glacier is often described as ‘the doomsday glacier’, due to the catastrophic effects if it collapsed.

Ella Gilbert, Postdoctoral Research Associate in Climate Science, University of Reading said in an essay for The Conversation: “Were it to empty into the ocean, it could trigger a regional chain reaction and drag other nearby glaciers in with it, which would mean several meters of sea-level rise.

“That's because the glaciers in West Antarctica are thought to be vulnerable to a mechanism called Marine Ice Cliff Instability or MICI, where retreating ice exposes increasingly tall, unstable ice cliffs that collapse into the ocean.

“A sea level rise of several meters would inundate many of the world's major cities – including Shanghai, New York, Miami, Tokyo, and Mumbai.

“It would also cover huge swathes of land in coastal regions and largely swallow up low-lying island nations like Kiribati, Tuvalu, and the Maldives.”

Thwaites Glacier is 74,000 square miles, the size of Great Britain, and is thought to be particularly susceptible to climate change.

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Even now, ice draining from Thwaites into the Amundsen Sea accounts for about four percent of global sea-level rise - as it dumps 50 billion tonnes of ice into the ocean each year.

But scientists speaking to the BBC warned in December that dramatic changes could occur within ten or even five years.

The scientists warn that a floating section of Thwaites Glacier could ‘shatter like a car windscreen.’

Prof Ted Scambos, US lead coordinator for the International Thwaites Glacier Collaboration (ITGC) said: "There is going to be dramatic change in the front of the glacier, probably in less than a decade. Both published and unpublished studies point in that direction.

"This will accelerate the pace (of Thwaites) and widen, effectively, the dangerous part of the glacier.”

ANTARCTICA -- FEBRUARY 28, 2021:  Maxar medium view satellite imagery of a pyramid looking mountain in Antarctica.  Please use: Satellite image (c) 2021 Maxar Technologies.
Many of the world's largest cities could be threatened if the glacier melts. (Reuters) (Maxar via Getty Images)

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Paul Cutler, programme director for Antarctic glaciology at America’s National Science Foundation said, “It is a keystone for the other glaciers around it in West Antarctica . . . If you remove it, other ice will potentially start draining into the ocean too.”

Cutler says that the Thwaites glacier is losing ice faster and faster, and that the process seems to be accelerating.

Cutler said, “The big question is how quickly it becomes unstable. It seems to be teetering at the edge.”

Teams of scientists are drilling into Thwaites Glacier, to find out if it’s about to collapse.

Over the past 30 years, the amount of ice flowing out of Thwaites and its neighbouring glaciers has nearly doubled.

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Rob Larter, UK principal investigator for the Thwaites Glacier Project at the British Antarctic Survey told the FT, “It is the most vulnerable place in Antarctica.”

The South Pole, the most remote place on the planet, has warmed three times faster than other areas over the past three decades, researchers say.

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