Predictions of Global Warming are not sufficiently pessimistic

[Wise Young]

http://www.indymedia.org.uk/en/2007/08/379803.html

George Monbiot Updates His Global Warming Book

reposted | 28.08.2007 16:15 | Ecology
Here is a portion of George Monbiot's speech at the Camp for Climate Change in London Aug. 18, '07. He has been studying and writing about global warming for over twenty years and is the Author of "Heat" which is about climate change and what needs to be done about it. He explains that because of recent scientific discoveries the book needs an extreme update.

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I'm going to start with some bad news, and the bad news is this. Two
degrees is no longer the target. And the news is contained in a recent
paper written by James Hansen of NASA in the Philosophical Transactions
of the Royal Society(1). And what Hansen shows is that the profoundly
pessimistic assumptions in the latest IPCC Report are insufficiently
pessimistic.

And the reason for this is as follows. The IPCC assumes that the melting
of the ice sheets at the poles will take place in a gradual and linear fashion.
And Hansen's own work with the paleontological record shows that that is
an "entirely implausible" (to use his term) scenario.

the last time we had two degrees of warming in the Pliocene 55 million
years ago, the ice sheets at the poles did not melt - as the IPCC proposes -
over a millennia, but within the course of one century. And they did not cause
a maximum sea level rise within the course of one century - as predicted by
the IPCC - of 59 centimeters, but of 25 meters.

And Hansen proposes that through a series of factors - the collapse of the
buttresses that prevent the ice from sliding into the sea, the melt water
trickling down through crevasses and lubricating the base of the ice sheets,
and melt water on the surface of the ice sheets changing the albedo, making
the ice darker and therefore absorbing more heat, will lead to the sudden
and - certainly in geological terms - almost immediate collapse of both the
West Antarctic and Greenland ice sheets within the course of one a century
at somewhat less than two degrees of warming.

Not only does this lead to the immediate affect of inundation of most of the
inhabited world - something like 60% of the people live within 50 Km of the
coast - it also means that you get a severe and sudden change in global
albedo change as white stuff at the poles gives way to dark stuff absorbing
much more solar radiation.

And he proposes that we can't go beyond 1.5 to 1.7 degrees of warming
above 1990 levels.

<more>

And I'm afraid the second uncomfortable message I have to put out to you tonight is that when it comes to dealing with a problem of this scale, small is no longer beautiful. We have to start thinking on the biggest possible terms....

We have very very little time in which to act. We have very very little time in which to bring about the largest economical and political transformation the world has ever seen.

Whew.