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The whole layer of Antarctic ice melts at an alarming rate: LifeStyle



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Last update enabled July 10, 2019 09:42

In the last decade, Antarctica lost 252 million tonnes of ice annually.

(Web Desk): to the west of the Antarctic, a glacier of the size of Florida is losing ice faster than ever. The sections of the Thwaites glacier retreated to 800 meters per year (2,625 feet) and contribute to 4 per cent of the rise in sea levels worldwide.

This loss of ice is part of a broader tendency: the entire Antarctic ice layer melts almost six times faster than it was 40 years ago.

In the 1980s, Antarctica lost 40 billion tons of ice annually. In the last decade, this number rose to an average of 252 million tonnes per year.

Now, the authors of a new study report that during the last six years the rate with which five Antarctic glaciers has doubled. This causes the Thwaites glacier to be a fusion bomb.

Scientists reported in the journal Proceedings of the National Academy of Sciences that the glacier is the biggest risk for sea level rise and is likely to move to an irreversible point of merger.

"After reaching the turning point, the Thwaites glacier could lose all its ice in a period of 150 years," said Hélène Seroussi, author of NASA's scientific and scientific study, in a press release

"This would mean a rise of sea level approximately half a meter (1.64 ft)".

Another study author, Alex Robel, added that if the glacier had to cross this Rubicon, nothing could stop the melting of the ice, although the temperatures of the Earth would stop growing.

"It will continue on its own and that is the concern," he said.


Why the Thwaites Glacier can reach a turning point


The Thwaites Glacier is a large mass of ice born from snow that has been compressed over time. It is part of the Antarctic ice layer: a large continental glacier that covers at least 20,000 square kilometers of land (around the United States and Mexico combined).

The Antarctic is surrounded by a skirt of ice sheets and floating ice shelves that create a physical barrier between the ocean and the landed ice of the continent. These floating sheets "act like a prey", as Ross Virginia previously said, director of the Institute of Arctic Studies at Dartmouth College. Business Insider.

The barrier prevents continental ice from flowing into the ocean, where it melts and causes global sea level to rise.

But as ocean temperatures increase, the warmest water in the base of these ice sheets causes them to melt below. This thaw creates cavities: in February a first size vacuum of Manhattan was discovered under the Thwaites glacier.

This cavity was large enough to contain 14,000 million tons of ice.

Every year, the part of the ice platform of the Thwaites glacier that extends to the sea increases as ocean water erodes its base.

Thus, scientists such as Seroussi and Robel keep track of Thwaites' land line: the place where continental ice rises from the ground and begins to float to the water. (Think of a spurt of land that is beyond the edge of a cliff in the air; it is the same concept with glaciers, except in place of air, ice it's on the water).

This land line moved almost 9 miles (14 kilometers) between 1992 and 2011, according to a 2014 study; The closer the interior moves, the more likely it is to melt the glacier.


What does a Thwaites melting glacier mean for sea level?


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

Most of this water is frozen in masses of ice and snow that can be 10,000 feet (3 km) thick.

But as human activity sends more greenhouse gases to the atmosphere, the oceans absorb 93 percent of the excess heat that is the gas traps. Hot air and water make ice sheets and glaciers melt at an unprecedented pace.

Seroussi said that Thwaites could reach his inflection point "in the next 200 to 600 years," after which he could lose all his gel.

If all the Thwaites glacier was melted, according to the recent study, there would be a rise of sea level of 1.64 feet worldwide (although another study that the rise was closer to 2 feet).

But Thwaites also prevents its neighboring glaciers from reaching the ocean. Thus, some other scientists think that if the entire Thwaites glacier collapsed, it could also destabilize the glaciers around the Antarctic ice layer.

If you were going away, everyone could go and this chain reaction would increase sea level by about 2 meters.

This article was originally published by Business Insider.

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