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Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Science https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ A giant Antarctic glacier is on its way to an irreversible melt

A giant Antarctic glacier is on its way to an irreversible melt



  • Antarctica glaciers melt at unprecedented prices. This fast istab contributes to increasing sea level.
  • In a new study, the researchers found that the Thwaites glacier in western Antarctica is likely to hit a point of irreversible melting, after which it will lose all its ice over 150 years.
  • If the entire Thwaites glacier were to melt, it would raise the sea level by at least 1.5 meters.
  • Some experts warn that the Thwaites glacier collapse could trigger a chain reaction of melting that would raise the sea level by another 8 feet.
  • Visit the Business Insider's website for more stories.

In western Antarctica, a glacier, the size of Florida, loses ice faster than ever before.

Sections of the Thwaites glacier retire by up to 2,625 feet per year, contributing to 4% of the world's highest rise. That ice tea is part of a wider trend: The whole of the Antarctic ice melts almost six times as fast as 40 years ago. In the 1

980s, Antarctica lost 40 billion tons of ice annually. Over the last decade, the number has fallen to an average of $ 252 billion. Tons a year.

Now, authors of a new study report that over the past six years, the rate at which five Antarctic glaciers slough off ice has doubled. This makes the Thwaites glacier a melting time bomb.

The researchers reported in the journal Proceedings of the National Academy of Sciences that the glacier poses the greatest risk of future sea level rise and is likely to march against an irreversible melting point.

"Having reached the tipping point, Thwaites Glacier could lose all its ice cream for 150 years," said Hélène Seroussi, a study author and a NASA scientist, in a press release. "It would result in an increase of about half a meter (1.64 feet) in the ocean."

Alex Robel, another study author, added that if the glacier was to cross the Rubicon, nothing could stop the ice melt – even though Earth's temperatures were no longer standing.

"It will continue in itself, and that is the concern," he said.

Why the Thwaites glacier can reach a drainage point

A gigantic cavity that is nearly 1,000 feet tall grows at the bottom of the Thwaites glacier in West China.
NASA / OIB / Jeremy Harbeck

The Thwaites glacier is a large amount of ice born of snow compressed over time. It is part of the Arctic sheet in Antarctica – a large continental glacier covering at least 20,000 square kilometers of land (on the surface of the United States and Mexico combined).

Antarctica is called by a skirt of ice sheets and floating ice shelves that create a physical barrier between the sea and the ice-locked ice on the continent. These floating sheets act as a dam, like Ross Virginia, director of Dartmouth College's Institute of Arctic Studies, previously told Business Insider. The barrier prevents continental ice from flowing into the sea where it will melt and cause global sea levels to rise.

But as the sea temperature rises, warmer water in the bottom of these ice sheets causes them to melt from below. This melting gives rise to cavities: An almost Manhattan hole was discovered during the Thwaites glacier in February. The cavity was large enough to have had $ 14 billion. Tons is.

Read more: There is a cavity under Antarctica that is two-thirds of the Manhattan size. A separated ice sheet melts faster than we thought

Every year, the part of the Thwaites glacier's floating ice shelf that extends into the sea becomes larger as sea water erodes its base. So scientists like Seroussi and Robel track Thwaites & # 39; ground line: the place where the continental lake lifts the earth and begins to float on the water. (Think of a spit land stretching past a rocky edge in the air – this is the same concept of glaciers, except for air, ice is over water.)

This landline moved nearly 9 miles between 1992 and 2011 , according to a 2014 survey The longer the inland site moves, the more likely it is that the glacier melts.

What a melting Thwaite glacier means to the surface of the sea

Along with Greenland's ice, Antarctic ice layer contains more than 99% of the world's fresh water.

Most of this water is frozen in lots of ice and snow that can be up to 10,000 feet thick. But as human activity sends more greenhouse gases to the atmosphere, the oceans absorb 93% of the excess heat that these gases trap. The hot air and water is what causes ice sheets and glaciers to melt at unprecedented prices.

Seroussi said that Thwaites could reach its tip "in the next 200 to 600 years", after which it could lose all its ice. If the entire Thwaites glacier melted, it would result in a worldwide rise of 1.64 feet, according to the recent survey (although another study estimated the rise to be closer to 2 meters).

A close look at the Thwaites Ice Shelf edge.
James Yungel / NASA via Wikimedia Commons

But Thwaites also prevents its neighboring glaciers from floating into the sea. So some other scientists believe that if the entire Thwaite glacier were to collapse, it could destabilize surrounding glaciers on the Antarctic Arctic sheet.

If you go, they could all go – and that chain reaction would raise the sea level by another 8 feet.


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