“IPCC Does Not Guard Itself Against Groupthink” – Richard Tol

On Friday last week (April 25), climate economists Richard Tol of Sussex University and Robert Stavins of Harvard University separately posted critiques of the process by which the Intergovernmental Panel on Climate Change (IPCC) drafts, edits, and approves the Summaries for Policy Makers (SPMs) of its huge assessment reports.

Tol caused a stir last month when Reuters reported that, in September 2013, he quit the 70-member team authoring the SPM of Working Group II (Impacts) of the IPCC’s Fifth Assessment Report (AR5). Tol said he pulled out because, “The drafts became too alarmist.”

According to Reuters (Mar. 27):

Tol said the IPCC emphasized the risks of climate change far more than the opportunities to adapt. A Reuters count shows the final draft has 139 mentions of “risk” and 8 of “opportunity”.

Tol said farmers, for instance, could grow new crops if the climate in their region became hotter, wetter or drier. “They will adapt. Farmers are not stupid,” he said.

He said the report played down possible economic benefits of low levels of warming. Less cold winters may mean fewer deaths among the elderly, and crops may grow better in some regions.

“It is pretty damn obvious that there are positive impacts of climate change, even though we are not always allowed to talk about them,” he said. But he said temperatures were set to rise to levels this century that would be damaging overall.

In an op-ed a few days later (Mar. 31), Tol explained his basic disagreement with the SPM perspective on climate impacts: “The idea that climate change poses an existential threat to humankind is laughable.”

In his April 25 blog post (“IPCC again”), Tol discusses the political dynamics shaping the WG2 SPM. Some key excerpts:

AR5 is a literature review of 2,600 pages long. . . .The SPM then distills the key messages into 44 pages – but everyone knows that policy and media will only pick up a few sentences. This leads to a contest between chapters – my impact is worst, so I will get the headlines.

In the earlier drafts of the SPM, there was a key message that was new, snappy and relevant: Many of the more worrying impacts of climate change really are symptoms of mismanagement and underdevelopment.

This message does not support the political agenda for greenhouse gas emission reduction. Later drafts put more and more emphasis on the reasons for concern about climate change, a concept I had helped to develop for AR3. Raising the alarm about climate change has been tried before, many times in fact, but it has not had an appreciable effect on greenhouse gas emissions.

I reckoned that putting my name on such a document would not be credible – my opinions are well-known – and I withdrew.

The SPM, drafted by the scholars of the IPCC, is rewritten by delegates of the governments of the world, in this case in a week-long session in Yokohama. Some of these delegates are scholars, others are not. The Irish delegate, for instance, thinks that unmitigated climate change would put us on a highway to hell, referring, I believe, to an AC/DC song rather than a learned paper.

Other delegations have a political agenda too. The international climate negotiations of 2013 in Warsaw concluded that poor countries might be entitled to compensation for the impacts of climate change. It stands to reason that the IPCC would be asked to assess the size of those impacts and hence the compensation package. This led to an undignified bidding war among delegations – my country is more vulnerable than yours – that descended into farce when landlocked countries vigorously protested that they too would suffer from sea level rise. . . .

The SPM omits that better cultivars and improved irrigation increase crop yields. It shows the impact of sea level rise on the most vulnerable country, but does not mention the average. It emphasizes the impacts of increased heat stress but downplays reduced cold stress. It warns about poverty traps, violent conflict and mass migration without much support in the literature. The media, of course, exaggerated further. . . .

The IPCC does not guard itself against selection bias and group think. Academics who worry about climate change are more likely to publish about it, and more likely to get into the IPCC. Groups of like-minded people reinforce their beliefs. The environment agencies that comment on the draft IPCC report will not argue that their department is obsolete.

Stavin’s post is also harshly critical of the SPM process, as indicated by the title: “Is the IPCC Government Approval Process Broken?”

Stavins is coordinating lead author (CLA) of Chapter 13, “International Cooperation: Agreements and Instruments,” of IPCC Working Group III (Mitigation).

Politically-driven editing was so pervasive in the WG3 SPM that Stavins and “several” fellow CLAs thought the document “should probably be called the Summary by Policymakers, rather than the Summary for Policymakers.” Stavins does not blame anyone in particular but rather a “structural” conflict of interests:

. . . . I do not believe that the responsibility for the problems that arose are attributable to any specific country or even set of countries.  On the contrary, nearly all delegates in the meeting demonstrated the same perspective and approach, namely that any text that was considered inconsistent with their interests and positions in multilateral negotiations was treated as unacceptable. 

To ask these experienced UNFCCC negotiators to approve text that critically assessed the scholarly literature on which they themselves are the interested parties, created an irreconcilable conflict of interest. . . . 

Over the course of the two hours of the contact group deliberations, it became clear that the only way the assembled government representatives would approve text for SPM.5.2 was essentially to remove all “controversial” text (that is, text that was uncomfortable for any one individual government), which meant deleting almost 75% of the text, including nearly all explications and examples under the bolded headings. . . .

I understand that country representatives were only doing their job, so I do not implicate them personally; however, the process the IPCC followed resulted in a process that built political credibility by sacrificing scientific integrity. . . .

The problem is structural, not personal.  In my view, with the current structure and norms, it will be exceptionally difficult, if not impossible, to produce a scientifically sound and complete version of text for the SPM on international cooperation that can survive the country approval process. 

Tol concludes that the IPCC should be “taken out of the hands of the climate bureaucracy and transferred to the academic authorities.” Stavins, too, implies that country delegations should be kicked out of the SPM drafting process.

I’m not sure how much that would help, since governments are the big winners from climate policy; they nominate most of the experts who serve as CLAs and lead authors; and they finance the entire process.

The notion, moreover, that IPCC bias stops at the SPM edge is a bit hard to swallow. The IPCC has an institutional interest in building the scientific case for global climate treaties. That is its raison d’être.

IPCC reports are assessments, which means the authors’ judgments inevitably influence the selection and presentation of evidence. What we get is not The Science but an interpretation of the science. It is not the whole story, as can be seen from Climate Change Reconsidered II: Biological Impacts, which reviews hundreds of studies on the environmental and health effects of global warming and carbon dioxide (CO2) emissions that WG2 either ignores or downplays.

Nonetheless, the Tol-Stavins reform couldn’t hurt and is simply common sense. As Donna Laframboise observed in July 2013 about the politicking over the SPM for WG1 (Physical Science), “If it [the IPCC] were a scientific body, scientists would summarize those 14 chapters and that would be the end of the matter.”