A jigsaw not a House of Cards

This is the blog post I was never going to write, its about climate change.

This post will contain pretty much no science, if you're interested in that then I've put some references at the end. Instead this is a post about my personal journey with anthropogenic global warming (AGW).

So why did I decide to write this now? A couple of reasons really: the Copenhagen Climate Summit is next week but mainly climategate, the publication of leaked e-mails and data from University of East Anglia Climate Research Unit. I was listening to the Today programme Radio 4 in the UK in the gym, I was so frustrated by their climategate piece I had to turn the radio off and start to compose this post in my head. It's the mindless spouting of John Humphrey's about something of which he clearly has no understanding which is frustrating.

My journey begin in 2007 when "The Great Global Warming Swindle" (TGGWS) was broadcast. Ben Goldacre wrote about it on his blog. People I knew started talking about it and the balanced view it presented: yet it was utterly at variance with what I knew about global warming. I still haven't seen "The Great Global Warming Swindle", nor have I see it's antithesis Al Gore's "An Inconvenient Truth". Subsequently OFCOM ruled that several scientists had been treated unfairly by TGGWS, and I decided that I was going to treat any further science broadcast by Channel 4 (the broadcaster) with overwhelming skepticism.

I say my journey began in 2007, but actually it began long before then. I've been reading New Scientist for the last 20 years, New Scientist is a popular science news magazine; I've also been reading Nature for quite a few years. Nature is a general scientific journal, with science news - getting a paper in Nature is like winning a gold medal at a national sporting event for a scientist. So by 2007 I had absorbed the conventional scientific view of on AGW via stories in the scientific press, In much the same way as I have conventional opinions on continental drift, evolution, the big bang, and mass extinction.

"The Great Global Warming Swindle" stimulated me to action, here was purportedly a scientific question which should have a scientific answer. First stop was the Intergovernmental Panel on Climate Change (IPCC) 3rd Assessment report published in 2001 succeeded closely by the 4th Assessment report published 2007. I focused on the Physical Science Basis (WG1): the Summary for Policymakers for this report is short (18 pages) and written in a pretty accessible style, the following chapters filling out the detail and referencing the primary peer-reviewed literature. This is the coal-face of science, it's where I publish my professional work. Ultimately I also got myself an undergraduate textbook on atmospheric physics and Spencer Weart's book on the history of climate science.

So how does a scientist get on outside their field? Well, the IPCC reports are no problem for me to understand. I can get on fine with understanding the abstracts of most the papers in the primary literature, but I would really struggle to contribute to this literature and I would not be able to pick out subtle errors, or judge between opposing expert views. This is unsurprising, because these papers will have passed peer-review and this means in most cases anything obviously wrong would have been weeded out.

I also plunged into the blogosphere, reading both contrarian and conventional sites. The only one I'll cite here is realclimate.org, a blog by climate scientists which reports on new papers in the literature - I still read this. It was in the blogosphere that I came to my conclusions on the contrarian view: it's wrong. I'll expand on that slightly, there's a huge bunch of stuff that's just rubbish from the scientific point of view, there's a smallish bunch of stuff where people from other areas of science have published work on climate science that may well be accurate for their field but the climate science looks a bit wobbly, there are a very few academic climate scientists who think that IPCC AR4 exaggerates the problem but on the other hand there are quite a few academic climate scientist who think AR4 was overly optimistic.

Thus armed with knowledge I set out to argue the scientific case for the existence of anthropogenic global warming... I think I gave up on arguing about AGW when, in an exchange on a discussion forum, I suggested reading an undergraduate text in atmospheric physics was a useful thing to do in understanding climate science and the response was "Just goes to show what you know", it seemed knowledge was counting against me - blind prejudice was what was required. I had mistakenly believed I was arguing a scientific case, when in fact most other people were having a political argument dressed up as a scientific one. Which is odd really because it never occurred to me that global warming was a political question.

It seems to be a characteristic of contrarians that they view climate science as a house of cards, that if they disprove the contents of a single scientific paper then the whole edifice will fall. Hence there are very long arguments about single papers such as the original hockey stick controversy. However, science is a jigsaw, not a house of cards: to test a piece of science you look at the pieces of science around it to see how they fit, rather than staring very hard at the one piece. This view of science also makes it less personal, nothing in science depends solely on the work of one person. If they didn't exist someone else would independently come up with the same result before too long.

People are naturally political, democratic animals. They like to consider both sides of a dispute and come up with what seems like an balanced solution. Science is not democratic, there is not a middle ground. If we vote on science, nature will not accommodate to match the outcome.

References

Intergovernmental Panel on Climate Change 4th Assessment Report (know as IPCC AR4 published 2007)
Copenhagen Diagnosis (an update the IPCC AR4)
Physics of Atmospheres by John Houghton
The Discovery of Global Warming by Spencer Weart