East Antarctica is
supposed to be different. It is extremely remote and cold. It doesn't
see such warm temperatures in the summer - yet - and so its ice tends to
remain more pristine.
"Many people refer to East Antarctica as
being too cold for significant melt," says Jan Lenaerts, a glaciologist
with the Utrecht University in the Netherlands.
"I mean there's marginal melt in summer, but there's not a lot."
That's
the common wisdom, at least, but it is challenged in a new study in
Nature Climate Change, by Lenaerts and his colleagues from universities
in the Netherlands, Belgium and Germany. They do so based on research
they conducted atop the very large Roi Baudouin ice shelf in East
Antarctica, which floats atop the ocean, and where they found a very
Greenland-like situation in early 2016.
The researchers had
traveled to investigate what had been described as a nearly 2-mile-wide
"crater" in the shelf, glimpsed by satellite, which some sources
believed had been caused by a meteorite. To the contrary, they found
that it was a large, 10 foot deep, icy lake bed. In its center,
meanwhile, were multiple rivers and three moulins that carried water
deep down into the floating ice shelf.
And even this, perhaps,
was not the most dramatic finding. The researchers also drilled through
the ice and found what they called "englacial" lakes, sandwiched between
the surface of the ice shelf and its base, which is in contact with the
ocean beneath it. They found 55 lakes in total on or in the ice shelf,
and a number of them were in this buried, englacial format.
This
meant that the ice shelf is anything but solid - it had many large
pockets of weakness throughout its structure, suggesting a greater
potential vulnerability to collapse through a process called
"hydrofracturing," especially if lake formation continues or increases.
That's bad news because when ice shelves fall apart, the glacial ice
behind them flows more rapidly to the ocean, raising sea levels.
But why was all this happening, and here?
http://www.nzherald.co.nz/world/news/article.cfm?c_id=2&objectid=11766187
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