Posted on 03/09/2011 8:54:27 AM PST by Ernest_at_the_Beach
Theres some surprising reaction to the press release we covered on WUWT recently.
Knowing how the massive ice sheets atop Antarctica and Greenland work is key to
predicting how global warming could raise sea levels and flood coastal cities. But a new study upends what scientists thought they knew. It turns out its not just ancient snow that makes up the ice sheets, but water deep under the sheets also thaws and refreezes over time.
To put it in non-scientific terms, lead scientist Robin Bell told msnbc.com, the study
redefines how squishy the base of ice sheets can be. This matters to how fast ice will flow and how fast ice sheets will change.
It also means that ice sheet models are not correct, she said, comparing it to trying to
figure out how a car will drive but forgetting to add the tires. The performance will be very
different if you are driving on the rims.
Reporting in this weeks issue of the peer-reviewed journal Science, Bell and his team
described how ice-penetrating radar peeled back two miles of ice a million years old in the
center of Antarctica.
In the antarctic the glass of water will never melt, it will freeze forever.........Since we know the ice will never melt in that glass, the question that needs to be asked is whether or not a glass of gin with ice will freeze over and is the antarctic the perfect environment for martinis
Okay, vodka martoonies too!
Even without geothermal activity, the sheer pressure of a mile deep ice sheet would keep the bottom portion in a liquid state. This is nothing new. See Lake Vostok.
Translation: We need more money to study the issue.
Could explain why CO2 in the ice cores is lower than expected....
Lot's of questions as I see it.
Ditto that TE.
Thanks for the link...good stuff.
I'm sorry but that is not accurate. Water under pressure will still freeze but the freezing point will be lowered only slightly. The fact that the bottom of Lake Vostok is unfrozen is due entirely to geothermal activity..........An analogy would be why you have to dig fence poles at a certain depth below your prevailing frost lines.
As a side note, the deepest known ice lies in the antarctic and rests 2,555 meters below sea level, where the ice is over 4 kilometers thick.
It was at the Vostok station that the coldest temperature ever observed on Earth (−89 °C (−128 °F)) was recorded on 21 July 1983. [1] The average water temperature is calculated to be around −3 °C (27 °F); it remains liquid below the normal freezing point because of high pressure from the weight of the ice above it. Geothermal heat from the Earth's interior warms the bottom of the lake. The ice sheet itself insulates the lake from cold temperatures on the surface.Source: http://en.wikipedia.org/wiki/Lake_Vostok
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At the base of any substantial glacier, there will be liquid water simply due to the pressure, with or without geothermal warming. Same in the oceans where you can seem water temps below 0C at great depths. It does not have to do with frost lines... simply the pressure that changes the freezing point of water. Pressure also raises the boiling point.
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