Home / Science / Antarctica’s “doomsday glacier” is in grave danger, new research confirms

Antarctica’s “doomsday glacier” is in grave danger, new research confirms



Scientists call it the doomsday glacier.

This is partly due to the fact that the Thwaites, a Great Britain-sized glacier in West Antarctica, is melting at an alarming rate: it is retreating about half a mile (2,625 feet) per year. Scientists estimate that the glacier will lose all of its ice in about 200-600 years. When it does, sea level will rise by approximately 1.6-2 feet (0.5 meters).

But the sea level rise wouldn’t stop there. Thwaites’s nickname comes mainly from what would happen after he disbanded.

At this time, the glacier acts as a buffer between the warming sea and other glaciers. Its collapse could bring neighboring ice masses into West Antarctica with it. Plus, that process would raise sea levels by nearly 1

0 feet, permanently submerging many coastal areas including parts of New York City, Miami and the Netherlands.

“It’s a major shift, a rewrite of the coast,” David Holland, a professor of atmospheric science at New York University who contributes research to the International Thwaites Glacier Collaboration, told PBS NewsHour in February.

This moth, two new studies have added details to the alarming picture. Research published last week in the journal Cryosphere found that warm ocean currents could erode the belly of the Thwaites Glacier.

A study released Monday, meanwhile, used satellite imagery to show that sections of Thwaites and its neighbor, Pine Island Glacier, are breaking up faster than previously thought. That work was published in Proceedings of the National Academy of Sciences.

The images below reveal what is happening to the Thwaites and nearby glaciers, along with what may happen in the future.

The melting of the Thwaites and Pine Island glaciers already accounts for about 5% of global sea level rise.

thwaites 1(Lhermitte et al., PNAS, 2020)

Over it: Satellite images between October 2014 and May 2019 show extensive damage to the Thwaites and Pine Island glaciers.

It’s not just the Thwaites – the Antarctic ice sheet is melting six times faster than it was in the 1980s. They lose 252 billion tons a year, compared to 40 billion tons 40 years ago.

If the entire Antarctic ice sheet melted, scientists estimate that sea level would rise by 200 feet (60 meters).

Before and after images taken from space show the Thwaites glacier dissolving into the sea.

“What the satellites are showing us is a disintegrating glacier,” Ted Scambos, a senior scientist at the University of Colorado, told NASA in February.

This rapid melting is happening in part because the natural tampons holding Thwaites and Pine Glaciers in place are breaking down, according to new research.

thwaites 2(Ian Joughin / University of Washington)

Over it: Cracks near the ground line of Pine Island Glacier, Antarctica.

Cracks like the ones in the Pine Island Glacier image above form near the cutting edges of glaciers – areas where fast-moving glacier ice meets slower-moving ice or rock, which keeps it contained.

The new PNAS one study found that the shear edges on the Pine Island and Thwaites glaciers are weakening and breaking, which could cause ice to flow into the ocean.

The looming loss of the Thwaites Glacier is so concerning that the US and UK have set up an international agency to study it.

That organization, the International Thwaites Glacier Collaboration, studies the glacier via icebreakers that can break through thick sheets of ice.

In February, researchers discovered a cavity nearly the size of Manhattan at the bottom of Thwaites.

thwaites 3(NASA / OIB / Jeremy Harbeck)

Over it: A nearly 1,000-foot-high cavity is growing at the bottom of the Thwaites Glacier in West Antarctica.

The cavity, which NASA scientists discovered using ice-penetrating radar in 2019, could contain 14 billion tons of ice.

The diagram below shows how warm underwater currents move under the glacier, slowly melting it from the bottom up.

(International Thwaites Glacier Collaboration)(International Thwaites Glacier Collaboration)

Over it: A 3D diagram of the Thwaites Glacier, illustrating the seafloor channels that can bring warm water to the bottom of the glacier and cause it to melt.

When ice sheets melt from below, they can lose their structure, causing them to melt even faster and disintegrate in the ocean, as Thwaites is doing.

The researchers calculated that the Pine Island Glacier has lost an area the size of Los Angeles over the past six years.

“These are the first signs we see that the Pine Island Ice Shelf is disappearing,” said Stef Lhermitte, satellite expert and lead author of the PNAS study, said the Washington Post.

“This damage is difficult to heal.”

According to a 2018 report, sea level rise could affect up to 800 million people by 2050.

thwaites 5(Central climate)

Over it: A projection of what New York City’s sea level would look like with 10 feet of sea level rise.

The report, from the C40 Cities climate network, found that rising sea levels could threaten the nutrition of 470 million people and regularly expose 1.6 billion people to extremely high temperatures.

This article was originally published by Business Insider.

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