Thursday , January 28 2021

Eastern Antarctic views are shuffling



Eastern AntarcticaImage rights
Michael Studinger / Nasa / Iceberg

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Eastern Antarctica has shown very little evidence of change in recent decades

Nasa says she discovered the first signs of a significant melting in the glaciers in East Antarctica.

The region has long been considered stable and is not affected by some of the most dramatic changes occurring elsewhere on the continent.

But satellites have already shown that the ice flowing into the ocean along one eighth of the east coast is thinned and accelerated.

If this trend continues, it has consequences for future sea levels.

There is enough ice in the drainage basins in this Antarctic sector to raise the height of the world's oceans by 28m if everything melts.

"This is water equivalent to four glaciers of glaciers," says Catherine Walker of NASA's Goddard Space Center in Greenbet, Maryland.

Gleasonologist describes in detail his work here at the meeting of the American Geophysical Union (AGU).

Other stories from the AGU meeting you would like:

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NASA

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Glaciers at Bayens Bay show the biggest change in behavior since 2008

Dr. Walker takes maximum advantage of a new initiative at the agency to handle a huge number of satellite imagery to get a more resolute and more timely insight into what is happening in Eastern Antarctica.

Previously, the scientists were aware that the Tetzian glacier in the area was experiencing melting, most likely as a result of its ending being bitter by the warm water coming out of the deep ocean. Almost everything else in this part of the continent is considered stagnant.

New satellite imagery and speeds change this view. They make clear that the nearby glaciers to Totten also start to react in a similar way.

Marked changes are found in the area of ​​Vincennes Bay and Denman only to the west and to Porpoise Bay and the shore of George VI to the east.

The Vincent Bay – which includes the Underwood, Bond, Adams and Vanderford glaciers – has the most tangible ice loss. The slope drops five times higher than in 2008, with a total drop of about 3 meters in height.

"They also accelerated about 3 percent of their speed in 2008, which sounds small, but it is significant enough to change the flow of these glaciers because they are very deep," said Dr. Walker.

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NASA

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Thorn has long been recognized as the fastest moving glacier in East Antarctica

Once again, topiing will probably be warm water that rises from the depth by shifting the sea ice and wind bridges in the region.

The changes that are happening are still pretty subtle and they are really noticeable because of the new automated computer tools that millions of satellite images shot from Antarctica will be looking for.

NASA is preparing to expand access to these tools through a project called the Inter-Mission Time Series of Land Ice Velocity and Elevation or ITS_LIVE.

"I think we can expect that over the next five to 10 years we will have many observations based on observations, such as what Catherine does for the new data coming online," said Alex Gardner glaciers at the Jet Propulsion Engine NASA in Pasadena, California.


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