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After the Climategate emails scandal of last winter, and discoveries of some embarrassing errors in the work of the Intergovernmental Panel on Climate Change (IPCC), its chairman, Rajendra Pachauri, asked the Inter-Academy Council (IAC) to review IPCC procedures. The IAC is a little-known branch of the Inter-Academy Panel, itself a little-known committee that connects national academic societies. It was a safe choice for Pachauri.

The last IAC report was a glowing tribute to alternative energy schemes, co-authored by Pachauri himself, along with current Obama administration appointee Stephen Chu and a group of others. So I do not expect much independence of mind or hard-headed objectivity from the IAC. But with the report due out on Aug. 30, I guess we shall soon see.

I was one of hundreds of people asked to respond to a set of inquiry questions. The questions, and my replies, are available on my Web page ( Here is a summary of some of my input.

IPCC policies, such as the requirement for an “objective, open and transparent” review process, sound impressive, but my experience is that the written policies are not always followed, and there do not appear to be any consequences when they are breached.

For example, one rule states: “Review Editors will need to ensure that where significant differences of opinion on scientific issues remain, such differences are described in an annex to the Report.” Yet no such annexes have been produced. I was involved in numerous areas where there were significant differences of opinion on scientific issues, such as flaws in surface temperature data, improper estimation of trend uncertainties and methodological flaws in paleoclimate research. None of these differences were resolved during the review process, yet no annexes were ever published, creating a false impression of consensus.

After the publication of the AR4 I found that important text had been altered or deleted after the close of the review process, and the Lead Authors of Chapter 3 had fabricated evidence (on Page 244 of the Working Group I Report), by claiming that statistical evidence in two published, peer-reviewed articles on surface data contamination was statistically insignificant, when the articles show no such thing. The paragraph was inserted after the close of peer review and was never subject to external scrutiny. That Lead Authors are able to insert evidence and rewrite the text after the close of review makes a mockery of the idea that the IPCC reports are peer reviewed, and undermines the claim that they contain the consensus of experts.

Selection of Working Group Chairs and Lead Authors appears to be under the control of a small circle of people committed to a predetermined view on global warming. In combination with the fact that the review process is toothless, this guarantees that the report contents are predictable given the names of the Lead Authors. Indeed there is not much point even publishing the report anymore: Once the list of Lead Authors is known, we can all guess what the conclusions will be. I am sure that there are many areas in the IPCC report where the conclusions will be sound. But in the areas where I have detailed knowledge and experience, this has not been the case.

A major problem with the IPCC is that the assignments for Lead Authors (LA’s) often put them in the position of reviewing not only their own work but also that of their critics. There is too much conflict of interest built into the report-writing process, and what few safeguards are in place are ineffective.

An example concerns the treatment of tree ring-based climate reconstructions in the Third IPCC Report. At the time, there were three studies presenting hemispheric temperature histories back to the Medieval era. One was by Michael Mann, whom the IPCC had picked to be Lead Author, and the others were by, respectively, Keith Briffa and Phil Jones (with coauthors).

Briffa’s study did not support the view that the 1990s were the warmest decade of the millennium. In principle, that should not be viewed as a problem. The task of the IPCC is to summarize the science, and if the science is uncertain, then that is what the summary should say. The problem is that Mann’s study claimed the 1990s were the warmest, and he had the discretion to impose a judgment, putting him in a conflict of interest. Mann (and Jones) dealt with Briffa’s counterevidence by simply deleting the divergent portion of his data from the graph in the report, without explanation. In the 2007 IPCC report, the same trick was applied. This time at least one expert reviewer noticed it (Stephen McIntyre) and objected, but the objections were dismissed.

The IPCC “peer review” process is not like the one academic journals use, in which reviewers actually have the authority to recommend rejection and require changes; instead it is more like a limited, voluntary public comment process. Since the IPCC gives Lead Authors the sole right to determine content and accept or dismiss comments, it is more like a weblog than an academic report.

In addition, no one is assigned the role of reviewing a particular section or chapter. It is conceivable that parts of a report might not be read by any reviewers: Nothing in the IPCC procedures prevents this.

Although there are more than 140 governments in the IPCC, only 23 governments submitted any review comments on the 2007 IPCC scientific report, and more than half of the comments were from only two countries: the United States and Australia. Not one African country submitted a comment, nor did any Middle Eastern or Arabic countries, nor did Russia nor the former Soviet states. Brazil submitted comments on three chapters and Chile commented on one chapter; other than that, there were no comments from any South American countries. None of the small island states in the Pacific submitted comments. In Eastern Europe, the Czech Republic commented on one chapter, and Hungary commented on three chapters; other than that, there were no comments from any government in Eastern Europe.

Yet the fact that all the member states “accepted” the report and its conclusions is routinely invoked as evidence of its authority. It is hard to see why the government review process even exists, except to serve as window dressing.

Ultimately, if the IPCC is going to have a review process at all, it has to delegate some actual authority to reviewers rather than treating them as chumps and discarding their input. In addition, there has to be a point in the review process at which an agreed-upon text is frozen and cannot be rewritten thereafter by Lead Authors after the reviewers have signed off.

The IPCC began before the Internet did, and its structure is now obsolete. It adopted a rigid bureaucratic structure that had some relevance in the days before the Internet imposed deep transparency on public organizations. But times have changed and public expectations have evolved. Henceforth, from the start of the chapter review process, the attention of international bloggers will be intense, and every aspect of the report-writing process will occur in a fishbowl. Without major reforms to the process, the next Assessment Report will simply explode on impact. All it will take is for one error to be found, or one email to be leaked, or one graph to be manipulated, and the entire report will be discredited.

This is not because there are armies of nasty, unreasonable bloggers out there. It is because the IPCC has become one-sided and brittle, and has no real ability to cope with legitimate differences of opinion. That makes it inevitable that there will be growing numbers of critics who see it as biased and insular. The choice is whether simply to press onwardº with the hope the IPCC will somehow regain its former glory, or to consider whether the critics actually have a point, in which case the process needs correction.

Ross McKitrick is a professor of economics at the University of Guelph.

Financial Post 28 August 2010