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Cracks Signal Massive Iceberg Forming In Antarctica
Several readers have submitted news (as covered by an AFP article carried by the Sydney Morning Herald) that a massive iceberg is forming in the Antarctic. The rift in the PIne Island Glacier "is widening at a rate of two metres a day, said NASA project scientist Michael Studinger. When the ice breaks apart, it will produce an iceberg more than 880 square kilometres, said Mr Studinger, who is part of the US space agency's IceBridge project. But the process is not a result of global warming, he said." Also at the BBC.
It seems reasonable and responsible to avoid this being dragged into the AGW/CC debate one way or another if the scientists concerned are pretty sure that CC plays no significant part in this event, because lots of glacier/calving activity *has* been tied to CC, pro or anti.
So, it wouldn't be ignorance that would lead people to wonder. And thus forestalling inappropriate linkage is good.
Rgds
Damon
http://m.earth.org.uk/
"...Intuitively, a block of ice breaking away from a bigger block of ice kinda makes me think there's melting, thus warming, involved..."
Why do you think that? This is the end of a GLACIER. Usually, glaciers move (slowly) downhill, until they reach warmer regions, where they melt. In this case the glacier moved downhill until it met the sea, upon which it floated out. After a fair bit has floated out, it will break off, due to flexing in the waves and tides. That is what has just happened, with a rather big bit...
Actually, if it is cold and snowy up in the mountains, the glaciers will move faster. And more bits will fall off the end of the glacier, more rapidly. This is often shot by journalists at the foot of the glacier, and used as 'confirmation of Global Warming'.....
A paper published in Nature back in December describes the cause: http://www.nature.com/ngeo/journal/v4/n8/full/ngeo1188.html
Here we combine our earlier data with measurements taken in 2009 to show that the temperature and volume of deep water in Pine Island Bay have increased. Ocean transport and tracer calculations near the ice shelf reveal a rise in meltwater production by about 50% since 1994. The faster melting seems to result mainly from stronger sub-ice-shelf circulation, as thinning ice has increased the gap above an underlying submarine bank on which the glacier was formerly grounded. We conclude that the basal melting has exceeded the increase in ice inflow, leading to the formation and enlargement of an inner cavity under the ice shelf within which sea water nearly 4C above freezing can now more readily access the grounding zone.
I am amazed by the amazement of how ignorant people are about how ignorant other people are.
Don't fight for your country, if your country does not fight for you.
On this image of antartic elevation http://en.wikipedia.org/wiki/File:AntarcticBedrock.jpg you can see alot of what we think of the continent of Antartica would actually be open ocean if the ice wasn't there. (As it's below sea level.)
Did you know 80 to 90% of the moderators on slashdot wouldn't recognize a troll even if one dragged them under a bridge.
As one of the readers who mentioned this in a submission: http://video.stv.tv/bc/ITN_041111_worldICEBERG04/?redirect=no is a good short video story version on this, including some graphics on ice flows and pictures of the crack. Quite well done. Not this isn't a GW/CC event, but it is a chance to see the formation of a crack in progress, which we do not always catch. All icebergs start with this cracking process, and icebergs form in warm and cold periods of history. Understanding the ice dynamics of how flows of build up turn into stress is the ice equivalent of studying plate tectonics: the science of large solid plates bending, cracking, and then failing.
Fugue for Aaron Swartz