Antarctica's troublesome 'hairdryer winds'

[nitpicker]

http://www.bbc.com/news/science-environment-39759329

Antarctica's troublesome 'hairdryer winds'

Jonathan Amos
Science correspondent

30 April 2017

From the section Science & Environment

It's an ill wind that blows no good - at least not for the ice shelves on the eastern side of the Antarctic Peninsula. A new study has found an atmospheric melting phenomenon in the region to be far more prevalent than anyone had realised. This is the foehn winds that drop over the big mountains of the peninsula, raising the temperature of the air on the leeward side well above freezing.

"The best way to consider these winds is how they translate to german now, which is 'hairdryer' ('Foen')," explained Jenny Turton from the British Antarctic Survey (BAS). "So, they're warm and they're dry and they're downslope. If you take the spring, the air over the ice shelf is usually minus 14 but during the foehn winds it’s above freezing.”
(snip)

Turton presented the foehn research at the European Geosciences Union General Assembly in Vienna. It is timely work because there is considerable interest currently in the status of the Larsen C Ice Shelf - a floating projection from the Peninsula that is the size of Wales. Scientists are wondering if this shelf will follow the demise of its siblings, Larsen A and Larsen B, further to the north. These collapsed in 1995 and 2002, respectively; Larson B doing so in spectacular style.

Larsen C shares some similarities - notably, the presence of those summer melt pools. This liquid water is problematic because of the way it can seep into crevasses and help to open them up. The water pushes down on the fissures, driving them through to the base of the shelf in a process known as hydrofracturing. They weaken the shelf.

"The thing about Larsen B though was that it was covered in them," recalled Prof Bernd Kulessa from Swansea University. "By the time the shelf reached a really weak state, there were literally thousands of ponds. On Larsen C, the ponds are still very much focussed in the inlets (close to the mountains). There are few ponds on the shelf itself and so it is not quite as pre-conditioned."
(snip)

[OnlinePoker]

1. Sounds like the Chinooks that can blow down from the Rockies into the Prairies

Temperatures can rise 40 degrees Celsius in a few hours.