Thwaites: Antarctic glacier headed for dramatic change

Scientists warn of drastic changes occurring at Antarctica's largest glacier, possibly within the next five to ten years.

14 December 2021 Tuesday 13:23
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Thwaites: Antarctic glacier headed for dramatic change

According to them, a floating section at Thwaites Glacier's front that has been stable up until now could "shatter like car windscreen."

Due to Thwaites' melt rate, researchers from the US and UK are currently involved in an intensive study program at Thwaites.

It is already dumping 50 million tonnes of ice each year into the ocean.

Although this is not having a significant impact on global sea levels today, there is enough ice upstream in the glacier drainage basin to raise ocean heights by 65 cm if it all melts.

Although such a "doomsday scenario" is unlikely to occur for many centuries, the study team claims that Thwaites is responding to a warming planet in very rapid fashion.

"There will be a dramatic change at the front glacier, likely in less than ten years." "Both published and unpublished studies point to that direction," stated Prof Ted Scambos (US coordinator of the International Thwaites Glacier Collaboration, ITGC).

He stated that this would "accelerate the pace (of Thwaites), and increase, effectively, the dangerous portion of the glacier," BBC News reported.

Thwaites: New maps show a vulnerability called 'Doomsday Glacier'

Climate change and the road to the "doomsday glacier"

"Boaty McBoatface" survives the ice missionThwaites was a huge. It is roughly the same size as Florida or Great Britain and its outflow speed doubled over the past 30 years.

This is what the ITGC has proven. It's the result of warm ocean waters melting Thwaites floating front or ice shelf.

Warm water thins and weakens this ice, making the ice run faster and pushing back the area where the main glacier body becomes buoyant.

The leading edge of the eastern Ice Shelf is currently held in place by an underwater ridge. This means that its flow speed is only a third of what is seen in the western Sector, which is free from such constraints.

The ITGC team believes that the eastern shelf will become detached from the ridge over the next few decades, which will cause it to be unstable. Even if the pinning continues, the continued development of fractures within the shelf ice almost certainly will break up the entire area. It's a bit like a car window with a few cracks, but then suddenly there is a bump and it starts shattering in all directions," said Dr Erin Pettit of Oregon State University.

Although the affected area is small, when viewed in context of the entire glacier, it is the shift towards a new regime and the implications for further ice loss that are truly significant.

The eastern shelf is currently moving forward at 600m per annum. It has a width approximately 40km. This change in status will likely cause the ice to accelerate by about 2km per annum, the same speed as the velocity in the 80 km-wide western sector.

The five-year ITGC project, jointly funded by the US National Science Foundation (USA) and the UK's Natural Environment Research Council (UK), places Thwaites under extraordinary scrutiny.

Every Antarctic summer season, scientists from all walks of the scientific community investigate the behaviour of the glaciers. Satellite, on the glacier, and even from ships right in front of Thwaites.

These teams are currently on their way to the new season, with some of them in Covid quarantine before they deploy to the field.

One of the New Year's projects will see the yellow submarine "Boaty McBoatface", also known as the "Boaty McBoatface", dive under Thwaites floating ice to collect data on water temperature and current direction - all factors that affect melting.

The autonomous vehicle will travel on one- to four-day missions, following its own route through the cavity below the shelf. The seafloor terrain is very rugged, so this is a high-risk mission.

"It's scary. "We might not get Boaty back," said Dr Alex Phillips, UK's National Oceanography Centre.

"We have spent a lot of time this year developing collision avoidance for our vehicle to ensure it doesn't collide with the seabed. There are contingencies that allow the vehicle to retrace its steps and return to safety if it gets into trouble.

This week, the American Geophysical Union Fall Meeting is in New Orleans will present the latest science about Thwaites Glacier.