I’ve written about the IPCCs way of reporting on science before, many times, and there is no doubt that its processes are deeply flawed. To begin with, it was set up to monitor the risks of human influences on climate, not on all influences on climate, and thus its bias is to prefer those papers that show, or purport to show, human influences at work. If, as seems increasingly likely, natural variability of many kinds is at least as important as human influences, if not much more so, then the need for an IPCC of the present kind begins to fade. It is understandable, then, that the IPCC reports keep telling us that warming is inevitable and we must reduce emissions.
Second, the IPCC has what amounts to a fetish about climate models, to the point where observations are dismissed, and model-run outputs preferred. It doesn’t matter how many times critics point out that the models have not been either validated or verified, or that their output is often at great variance with observations, the IPCC goes on talking about model runs as though they amount to ‘experiments’ that produce ‘evidence’.
Now someone has gone into the inner workings of the production of the WG1 scientific paper of AR5, looking at all the comments on what is known as the ‘second order draft’ (SOD — I make no comment). The SOD is the penultimate version of WG1, and the IPCCs procedures allow reviewers to comment; all comments have to be responded to.
A good process? Well, it could be. John McLean, who is a PhD student in climate science with some publications to his credit, decided that he would look at the whole process of turning the SOD into WG1, and that must have taken an awfully long time. I am glad that I didn’t have to do the work involved — but then, neither did he. But he was a reviewer for WG1, and he made a lot of comments — indeed, he must get whatever medal is awarded for making the greatest number of comments: 531. How many reviewers were there? The answer is 831. How many reviewer comments were there in all? 31,021. Amazing.
You can get access to his report on the whole process here, where you can download the report. The statistics are staggering, but what is most memorable, to me, is the dismissal and its tone, when any reviewer pointed out difficulties with models, or the different story observations tell. Chapter 10 of WG1, which is about ‘attribution’ (who dunnit?), is the one to check here. McLean points out that If a substantial part of any warming cannot be attributed to human influences then the rest of the IPCC report is worthless, save for some reasonable summaries (but doubtful interpretations) in the three chapters dealing with observations. I made the same point recently about ‘climate sensitivity’: if it is small, then what are we worrying about?
Chapter 10 was defended strongly, and so was the SOD of the Summary for Policmakers. McLean says The word “evidence” appears 236 times in the comments and responses, frequently in a form similar to “Reject. Reviewer fails to provide scientific evidence in support of his claims”. The phrase “fails to provide” appears 22 times in the IPCC author responses. ‘Evidence’ has to be peer-reviewed article, or the authors won’t have a bar of the criticism. I would call that a most constipated approach to review.
McLean has a neat summary of the whole process, based on his analysis of the comments and their reception.
Here’s how it works
(i) The IPCC produces a report citing published papers and predicting significant warming; governments approve the summary of this report and it becomes the authoritative version.
(ii) Governments bow to pressure from peer governments, the United Nations as a whole, the United Nations Environment Program and the United Nations Framework Convention on Climate Change. This pressure is both direct from these bodies and indirect via the alarmist media statements that these bodies produce and the mainstream media uncritically reports and which the public, who vote governments into office, blindly accept.
(iii) The substantial government-funded research that seeks to support the IPCC’s view results in even more papers for the next IPCC report to cite and conversely a reduction in papers that suggest other causes, the reduction being seized upon as evidence that few scientists support any contrary view.
McLean’s report has all the statistics that anyone might want, but it also has some most interesting commentary, of which I’ve provided only a flavour.
And to finish, here’s an extract from one reviewer who sums up the whole IPCC process for me in what follows:
The logical fallacy of this Chapter is in making the (implicit and ever present in the Report) statement that it is the anthropogenically produced carbon dioxide that is causing the global warming, based on the knowledge that carbon dioxide and other greenhouse gases affect climate to some extent. In other words, they accept the AGW hypothesis as final truth, without even trying to use the Scientific Method and test the hypothesis.
You won’t be suprised to learn that his comment was not accepted.