Scientists warn of drastic changes at Antarctica’s largest glacier.
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 in the next ten years, most likely in less than a ten year. “Both published and unpublished studies point to that direction,” stated Prof Ted Scambos (US coordinator of the International Thwaites Glacier Collaboration).
He stated that this would “accelerate the pace (of Thwaites), and increase, effectively, the dangerous portion of the glacier,” BBC News reported.
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Thwaites is a giant. It is roughly the same size as Great Britain or Florida 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 that of 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, fractures in shelf ice almost certain to break up the area.
“I imagine it somewhat like that car window with a few cracks and they are slowly growing, then suddenly you bump into a bump and the whole thing starts to shatter,” 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 80km-wide western section.
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 the ships directly 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.
