Six degrees: our future in six posts

A compressed and referenced version of Mark Lynas' data-rich book on global warming

Mark Lynas' Six Degrees is a fine book and a paradise for climate change activists, but it calls out for compression. For climate change newbies out there, the 2007 book (republished 2008) takes each degree of possible warming -- from one to six -- and catalogues the likely consequences they will bring for climate, geography, and life on earth. "Catalogue" is the right word, since Lynas (a UK journalist) based the book on a systematic study of peer-reviewed articles he found in the Oxford University Radcliffe Science Library.

Lynas clearly did his homework. In the 56 pages of the chapter on Three Degrees, I count 102 separate references to peer-reviewed articles and other respectable authorities (this excludes newspaper articles, press releases, and Worldwatch Magazine, but includes government, UNESCO, and WWF reports). That's almost two per page, which may not be a lot for an academic paper, but is rare for a 300-page popular book.

Lynas' research ethic has a downside. It means that Six Degrees is a bit like listening to Lord Stern talk about the economics of climate change -- you are soaked in a torrent of very informative details, but once the flood has passed you feel a bit damp and confused. Plus there is a lot of froth in the book, speculative sketches of a warming world that go beyond the published science.

What one wants is a neat row of frozen facts that one can pick up, examine at leisure, and launch at any passing skeptics. To this end I am going to list 5-10 of the most striking and well-supported scientific results in each chapter, starting with One Degree and moving up the mercury. To be useful, the items on the list need to be:

authoritative: no NYT articles or press releases
consensual: ie. Lynas doesn't cite any contrary evidence (fallible, I know, but the best I can do here)
convincing: a study of the extinction of six species is more convincing than a study of one
novel: ie. I haven't heard about them before -- shockingly subjective, but again it's the best I can do
powerful: if their predictions come true, they will effect large numbers of people and/or people close to home, where "home" is England
precise: numbers are better than words

Six Degrees was so successful that it is unlikely that any of the results are really novel. By now most of them, from the greening of the Sahara to the melting of Peruvian glaciers, have probably been raked over by skeptics and activists alike. But jogging the memory is an excellent form of exercise.

Some of the results in the book may been challenged since 2007. And there is no guarantee that Lynas has given us a representative sample of the peer-reviewed literature on climate change (though I'm inclined to think he has, given the scale of his research and his willingness to report countervailing results, when they arise). So the next six posts may give a lop-sided view of the consequences of warming. But as Lynas shows -- and as the next six posts may show -- that view has a lot going for it.