Planet Earth - Geothermal Heat in Antarctica

There have been very inaccurate stories on various websites claiming ......

"Volcanoes are the main reason for ice melting in Antarctica."

This is not the case.

The story is mainly a misreading of research on the Thwaites glacier.
This is the actual paper about this research......
            
So what actually is happening? 

 The Thwaites Glacier is behaving more like a warm-based glacier.



The geothermal heat from under the Thwaites glacier is small compared to the overall warming happening around Antarctica.
The Thwaites Glacier is one of a number of glaciers in that part of Antarctica.
“It is true that there are active volcanoes in West Antarctica, and so there may have been some local changes, but in most cases, at most times, volcanoes are not erupting under the ice,” Richard Alley, a geologist at Penn State University, told VICE News. 

“This paper doesn’t tell you anything about why the ice is now thinning.”

Eric Rignot, an earth science professor at University of California Irvine and a principal scientist at NASA, said geothermal heating causes a few millimetres of glacial melting each year.

 Rising sea temperatures can melt up to 100 metres of a glacier each year, he said.A photo of Thwaites glacier in West Antarctica taken by NASA Operation IceBridge. A new study finds a rapidly melting section of the West Antarctic Ice Sheet appears to be in an irreversible state of decline, with nothing to stop the glaciers in this area from melting into the sea. Credit: NASA     A NASA photo of the Thwaites Glacier at the point it meets the ocean.

 The heat flow out of the crust is highest at the spreading ocean ridges.

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