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Antarctic bulge could flood Washington DC
02-07-2009, 05:44 AM,
#1
Antarctic bulge could flood Washington DC
Antarctic bulge could flood Washington DC

* 19:00 05 February 2009 by David Robson

[Image: dn16545-1_300.jpg]

Rather than spreading out evenly across all the oceans, water from melted Antarctic ice sheets will gather around North America and the Indian Ocean. That's bad news for the US East Coast, which could bear the brunt of one of these oceanic bulges.

Many previous models of the rising sea levels due to climate change assumed that water from melted ice sheets and glaciers would simply run into the oceans and fill them uniformly. These models predict a 5-metre rise in sea levels if the West Antarctic ice sheet melts, but fail to acknowledge three important factors.

First, Jerry Mitrovica and colleagues from the University of Toronto in Canada considered the gravitational attraction of the Antarctic ice sheets on the surrounding water, which pulls it towards the South Pole. As the ice sheet melts, this bulge of water dissipates into surrounding oceans along with the meltwater. So while the sea level near Antarctica will fall, sea levels away from the South Pole will rise.

Once the ice melts, the release of pressure could also cause the Antarctic continent to rise by 100 metres. And as the weight of the ice pressing down on the continental shelf is released, the rock will spring back, displacing seawater that will also spread across the oceans.

Redistributing this mass of water could even change the axis of the Earth's spin. The team estimates that the South Pole will shift by 500 metres towards the west of Antarctica, and the North Pole will shift in the opposite direction. Since the spin of the Earth creates bulges of oceanic water in the regions between the equator and the poles, these bulges will also shift slightly with the changing axis.
Washington awash

The upshot is that the North American continent and the Indian Ocean will experience the greatest changes in sea level - adding 1 or 2 metres to the current estimates. Washington DC sits squarely in this area, meaning it could face a 6.3-metre sea level rise in total. California will also be in the target zone.

"Policy-makers must realise that the effects could be greater or smaller in different areas," says team member Natalya Gomez. The team have so far only considered one ice sheet, so the effects of other ice sheets across the world could also have a similar impact, she says.

However, these models assume that all the West Antarctic sea ice will melt, but Peter Convey from the British Antarctic Survey in Cambridge points out this may not necessarily be the case. "It would be dangerously easy to get people to focus on the 6-metre figure, but it just might not happen like that," he says.

Jonathan Gregory from the University of Reading in the UK, who is part of the Intergovernmental Panel on Climate Change, however, thinks the work should be helpful once this has been reliably evaluated.

Journal reference: Science: DOI: 10.1126/science.1166510

http://www.newscientist.com/article/dn1654...hington-dc.html
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02-07-2009, 07:33 AM,
#2
Antarctic bulge could flood Washington DC
Antarctic shelf collapse could tilt Earth's axis: researchers

By Dan Karpenchuk in Toronto

Posted Fri Feb 6, 2009 7:00pm AEDT

A new study in Canada suggests that the collapse of a large portion of the Antarctic ice shelf would shift the very axis of the planet.

Geophysicists at the University of Toronto looked at the possible effects on the earth if sea levels rise because of a collapse of the west Antarctic ice shelf.

The Toronto researchers say the melting of the ice sheet will actually cause the earth's rotation to shift dramatically - about 500 metres from its current position if the entire ice sheet melts - and that would result in much higher sea levels in some areas than previously expected.

The researchers say the melting would change the balance of the globe in much the same way that tsunamis move huge amounts of water from one area to another.

They say that could mean water migrating from the southern Atlantic and Pacific Oceans north toward North America and into the southern Indian Ocean.

The research has been published in today's issue of the journal, Science.


http://www.abc.net.au/news/stories/2009/02/06/2484792.htm
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02-07-2009, 09:31 PM,
#3
Antarctic bulge could flood Washington DC
With D.C. possibly going under, at least there's an upside to the possible changes on Earth.:P
“Today’s scientists have substituted mathematics for experiments, and they wander off through equation after
equation, and eventually build a structure which has no relation to reality. ” -Nikola Tesla

"When the power of love overcomes the love of power the world will know peace." -Jimi Hendrix
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02-07-2009, 10:24 PM, (This post was last modified: 02-07-2009, 10:25 PM by JazzRoc.)
#4
Antarctic bulge could flood Washington DC
Quote:With D.C. possibly going under, at least there's an upside to the possible changes on Earth.
One lives in hope...

Alternatively, a truck bomb jammed in La Palma's western cliff could do the same thing, albeit temporarily. Would that do?
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