Saturday, 9 January 2010

Book Review: Fred Pearce, "The Last Generation: how nature will take her revenge for climate change"

Right from the start I had mixed feelings about this book. Fred Pearce is a science writer who I respect. Recently he published an article pointing out that there are reasons other than the risk of climate change for cutting back on the use of fossil fuels, citing their use for the production of artificial fertilisers. This corresponds to my own view which is that fossil fuels are a finite resource, at some point in the future they will inevitably be exhausted and the sooner we start to plan our transition the smoother it is likely to be. Also a few years ago he published a longish article in New Scientist based on some of my work which has prejudiced me in his favour.

On the other hand I believe that books with cover (front and back) pictures of a city engulfed in flames and alarmist titles like “The Last Generation” are counterproductive. Particularly when the only review quoted on the front cover reads “This is the most frightening book that I have ever read.” (Eat your heart out Stephen King.) So how did I resolve my conflicts?

The book is, literally, wide ranging. Polar research stations, Brazilian rain forests, the Sahara, Indonesian peat bogs, Siberian permafrost and glaciers in the four corners of the earth: all are part of the climatic picture he presents. In many cases the author has been to the parts of the world he is talking about: when he has not he has still managed to talk face-to-face with most of the scientists involved.

The science is accurately covered but not always without bias. He is too kind to Michael Mann and his Hockey-stick. The book was of course written before the release of the CRU emails but the Wegman report, which he does not mention, should have alerted him to the fact that other papers from a small group of authors which also produce ‘hockey-sticks’ could not be considered as independent confirmation.

Anybody who has studied climate change can be forgiving for thinking of it as a gradual process. The sedate dance of the earth and sun which follows the Milankovitch cycles of 20,000, 40,000 and 100,000 years. The 1,500 cycle which is so gentle that some people doubt its existence. The 11 year sunspot cycle which occasionally produced a diminuendo but always follows it by a gentle crescendo. What this book does is to show that this is not the case; that large changes in temperature, falls and rises, can come about in periods measured in decades rather than centuries or millennia.

Some of these changes are well attested, the Dansgaard-Oeschger events for example. Temperature estimates from Greenland ice cores these show that temperature can rise 2 to 10 C in a decade, remain there for a century or so and then fall. Others are more speculative. It is known that the warming from the last ice age was interrupted and the earth’s temperature dropped again for more than 1,000 years. The widely accepted reason for this is that vast quantities of dammed up melt water flowed suddenly into the north Atlantic and interrupted the circulation of the oceans. Some scientists speculate that melting caused by global warming could have a similar effect.

Whilst it alright for Stephen King to generate tension among his readers by hinting at vaguely defined dangers it does not go well with a scientific explanation of climate change. The author recognises this and is open about the fact that even when the speed and magnitude of the changes to climate are well supported by scientific evidence there is little agreement on what caused them. He says “After many generations of experiencing global climate stability, human society seems in imminent danger of returning to a world of crazy jumps. ...There is still a chance that the jumps won’t materialise... but the chances are against it.”

Whilst those who are already firmly convinced that global warming is a serious and imminent threat will find new arguments in this book many dyed-in-the-wool sceptics will remain unconvinced. I work with a wide variety of scientists from many different disciplines and nothing annoys them more than phrases such as “the science is settled”; they know from their own experience that science rarely achieves that degree of absolute certainty. A book like this which describes the science accurately and is honest about the uncertainties is more likely to convince open minded sceptics than one which only presents one apocalyptic side of the story.

So, Fred Pearce has retained my respect. But what about the title. Well, in the chapter on “Conclusions” he back-tracks a bit. He explains that he did not mean the title to imply that we would be last generation ever to live, only that we would be the last generation to live with certainty of a stable climate. I suspect that the publisher believed, rightly unfortunately, that an accurate title such as “Climate instability: a balanced review of the possibilities and uncertainties” would not sell.


Eden Project Books
ISBN: 9781903919880

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