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NASA Data Reveals Mega-Canyon under Greenland Ice Sheet

63 points| olefoo | 12 years ago |nasa.gov | reply

22 comments

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[+] ovis|12 years ago|reply
I wonder how much this new map will effect model predictions of ice velocity and dynamic mass balance. Ice thickness measurements are important for calculating the stresses required to model ice velocity, and these are in turn relevant to predictions for the ice sheet's future because they affect how the ice might respond, for example, to increased melting at either the surface or coastal margins.

I would also be interested in seeing simple calcs of hydraulic potential with the new bed geometry. I wonder if water is still routed along this canyon?

[+] madaxe|12 years ago|reply
Almost certainly. They even say so in the article. Most glacial melt flow is subsurface - disappears down a moulin and flows out under the overhanging shelf, accelerating melt. Feedbacktastic.
[+] jmadsen|12 years ago|reply
Says at the end that "it may play a major role in transporting melt water...into the Arctic Ocean"

Seems to me, we just need to dynamite it shut and Presto world saved from eventual catastrophic flooding.

Don't everyone thank me at once.

[+] U2EF1|12 years ago|reply
Just think, within our lifetimes we'll be able to explore this canyon by foot.
[+] coldtea|12 years ago|reply
Yay!

Millions might have perished from the global warming and it's adverse weather and sea-line effects, but we could explore Greenland, so who cares about that.

[+] ddeck|12 years ago|reply
Perhaps with some deep sea diving gear. The surface of Greenland's bedrock is close to sea level in the interior and the discovered canyon appears to in the area that is below sea level.[1]

In addition, it's estimated that a complete melting of the ice sheet would increase sea levels by ~24ft[2] and that's not taking into account the larger impact of the rest of the world melting (Antarctic ice sheet is much larger).

[1] http://commons.wikimedia.org/wiki/File:Topographic_map_of_Gr...

[2] http://en.wikipedia.org/wiki/Greenland_ice_sheet

[+] Shivetya|12 years ago|reply
I am not sure if anyone could live long enough, there are some theories that suggest that when a sufficient amount of Greenland's ice cover melts it cools the oceans enough to restart the cooling cycle.

Earth seems to have a lot of built in corrective measures, for both the issues it causes and the ones we think we cause.

[+] jaekwon|12 years ago|reply
I read that as "huge crayon", and for a moment thought all my long held suspicions had proven true.
[+] jtms|12 years ago|reply
I read it as both "NSA" instead of "NASA" AND "crayon" instead of "canyon".