Scientists may have only identified the Achilles heel of the Thaits Glacier.
This Antarctic colossus is melting at a rapid rate, throwing billions of tons of ice into the ocean each year and raising global sea-level.
Now, a UK-US team has surveyed the deep seabed channels in front of the glacier that provide almost hot water access to infiltrate and attack the lower reaches of the Thaits.
That is the information that will be used to try to predict the future of ice flow.
“These channels have never been mapped in this kind of detail before, and what we’ve found is that they’re actually much bigger than anyone thought – up to 100 m. Thana. Think back six football pitches,” said Dr Kelly. . Hogan of the British Antarctic Survey (BAS).
“And because it is so deep and wide – the floating front of these whites as well as its ice that sits on the shore allow more water to melt and melt,” he told BBC News.
Why is the Thaits Glacier so important?
The whites flowing west of the Antarctic continent are as large as Great Britain.
It’s a rosy view, with its cheerful front or “ice shelf”, protruding too far into the ocean and carving out a huge iceberg. But satellite monitoring indicates that this glacier is melting at an accelerated rate.
It lost more than 10 billion tons of ice that year in the 1990s. Today, it is about 80 billion tons. The reason for the melting is believed to be the rush of relatively warm bottom water drawn from the vast ocean.
Currently, the loss of Thai ice contributes about 4% to the annual rise in global sea-level, with a total of 65 cm. Is likely to be added.
Some think this will happen in the short-medium term, but whites are considered particularly vulnerable in the warming world, and scientists certainly prefer to know how quickly any change happens.
What does the latest research show?
The UK and USA joined forces in 2019 to investigate Thwets.
Their scientists found the shape of the glacier’s icebergs, the bottom of a ship equipped with an echo-sounder.
The plane also flew back and forth on the shelf to measure small differences in gravitational pull. These deviations reflect the irregularity of the seabed below the shelf.
The two datasets taken together now offer the best view of the topography under Thaits. They find their way into a network of deep channels that cut through a rigidity before joining any large cavities under the ice shelf.
“The connected channels that we’ve mapped in detail for the first time are potential ways to get into the warm waters of the deep ocean and damage the place where the glacier is still in the coastal land, where it starts to lift. And float,” said a BAS ally. Dr. Tom also explained to Jordan, “But to melt the base of the ice shelf, which will make the ice in the glacier flow more upward if you weaken it.”
How will the new survey information be used?
Scientists need real-world data to coral their models models so that when they run simulations of future behavior, they get real results.
The new information improves the volumes for differentiating hot water that can be considered possible under different scenarios.
In their survey, even scientists now have a better idea of the general roughness of the coast.
This tells them about the different types of ice in the glacier that it moves towards the rock and silt. What the researchers have produced, if you like, is a kind of “stickiness index” to limit computer models.
What is likely to happen in the near future?
At the moment, the east side of the ice shelf is bent over a wide ridge, which gives it stability. But the current melting trend indicates that the situation will not last long, says Dr. Robert Larter of BAS.
“When the eastern ice shelf is unpinned, the ice will spread and thin, eventually breaking, because we can see the glacier happening right now (in the middle) on the tongue.” “Even before the ice shelf break-up, unpinning and thinning will reduce the impact of the ice shelf on the flow above its glacier, resulting in increased ice flow velocity. This in turn will accelerate the retraction of the glacier and grounding line.”
British and American scientists had to temporarily suspend their investigation into thwats due to the Covid-19 crisis.
The teams were due to return to the glacier this summer, but the remoteness of the location means the risks are much higher if anyone falls ill. Once the coronavirus outbreak, scientists will return, however.
“It’s amazing to see the change happening right before your eyes in a place like Thwites,” said Dr. Hogg. “When we were there in 2019, we could easily reach the ice shelves, and we could do that and make observations because the historically ever-living icebergs and sea-ice have begun to disappear.”
The latest research has been published in two papers in George Kreifier and can be accessed here and here.
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