Bill Totten's Weblog

Sunday, September 02, 2007

Updating the book on global warming

by George Monbiot

Here is a portion of George Monbiot's speech at the Camp for Climate Change in London August 18 2007 {1}. He has been studying and writing about global warming for over twenty years and is the Author of Heat (South End Press, 2007) 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. (August 31 2007)

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 {2}. 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 sixty per cent of the people live within fifty kilometers 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.

Combine this with what Richard was talking about and the stuff contained in the IPCC's 4th Assessment Report which shows that in order to have a maximum cap of two degrees of warming we need an 85% global reduction even before you take population growth into account. So when that's added to the fact that we're going to have something like a fifty per cent increase in population, you can see that that pushes way over ninety per cent even before you take the issue of global equity into account which means that the rich nations must cut the emissions much further than anybody else, you realize that we are talking at a minimum of a 100% cut, and it looks like it might have to go to 110% or 115%.

You laugh but we're talking about sequestration and we're talking about such things for example, as growing bio fuel and burying it, simply for growing as much bio mass as we can and sticking it back on the ground ... something ... anything to stave off this catastrophe.

We're not talking anymore about measures which require a little bit of tweaking her and there, or a little bit of political tweaking here and there. We're talking about measures which require global revolutionary change.

And that is a much tougher message than any that I've put out before, and this is the first opportunity really that I've had since that paper came out, to express the fact that what I thought were rather bold and revolutionary proposals in my book Heat, those proposals don't go nearly far enough. Those proposals have been superseded and we need to start thinking on a different scale altogether ...

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.


{1} The entire speech along with other speakers can be listened to free online courtesy of the UK IMC. Mr Monbiot is the second speaker at fifteen minutes in.

{2} Dr James Hansen's Paper (July 15 2007)

Bill Totten


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