In addition to providing regular assessments of scientific literature, the Intergovernmental Panel on Climate Change Process (IPCC) also produces a "Summary for Policymakers" intended to highlight relevant policy issues through data.
While the summary presents powerful scientific evidence, it goes through an approval process in which governments can question wording and the selection of findings but not alter scientific facts or introduce statements at odds with the science. In particular, during this process, the most recent summary on mitigation policies was stripped of several important figures and paragraphs that were in the scientists' draft, leading some IPCC scientists to express concerns about excessive political intrusion.
Delicate issues of political interpretation cannot be avoided, wrote three IPCC authors in the journal Science. In their analysis, the team – which includes Marc Fleurbaey from Princeton University's Woodrow Wilson School of Public and International Affairs – uses global emissions data to show how multiple political interpretations can be made from the same dataset. They argue that the IPCC should consider a writing process that better connects scientific findings with multiple political outcomes.
"The IPCC should consider opening up more channels for dialogue in which salient political discussions are connected to relevant scientific material," said the article's co-author Marc Fleurbaey, the Robert E. Kuenne Professor in Economics, Humanistic Studies and Public Affairs. "Such a collaboration or coproduction is what lends the IPCC its credibility as the voice of scientists – but with more weight for policy."
While the IPCC undoubtedly produces the most up-to-date, comprehensive scientific reports on climate change, its approval process has become tediously extensive. As the panel embarks upon its sixth assessment, those involved have been working toward streamlining the process.
In their review, Fleurbaey and his co-authors – Navroz Dubash from the Centre for Policy Research in India and Sivan Kartha from the Stockholm Environment Institute – write that this approval process sets the IPCC apart from other technical reports. Instead of changing the approval process, they suggest an alternate vision for articulating science and policy at the IPCC.
To illustrate their vision, the researchers analyzed global emissions by reviewing income growth across countries, a key driver of emissions growth. When looking at income, countries are sometimes grouped into such categories as lower-income, lower-middle income, upper-middle income and high-income. The trouble, however, is that some countries are rapidly changing in terms of income, which elides relevant information. Likewise, a few big countries can dominate the statistics, and the time reference used for grouping them also can lead to large differences.
When global emissions are analyzed according to groupings based on current income figures, upper-middle income countries account for 75 percent of the rise in global emissions from 2000 to 2010. This presentation of data was deleted from the recent summary report. A political interpretation of this, Fleurbaey and his collaborators write, may be that country groupings should reflect the increasing role of upper-middle income countries and perhaps impose commensurate emission limits.
However, when grouping countries according to their income in the middle of the decade (2005), global emissions rose three quarters in lower-middle income countries, a change due in part to the fact that China joined the upper-middle income group in 2010 only. This presentation highlighting lower-middle income countries may suggest supporting these countries financially and technologically in developing lower carbon economies.
"As you can see, both representations would be equally faithful to the underlying data, but they are also equally synthetic and incomplete, and they differ markedly in their political extrapolations," said Fleurbaey. "It's hard to accurately group these countries without imposing political perceptions, and analysis by country groups is highly sensitive in the current context of the renegotiation of the groups defined in the Kyoto protocol."
As an illustration that more positive outcomes can be obtained from governmental dealings, the authors report that some sections benefited from the approval process, as they were eventually expanded and clarified by additional explanations. For example, the framing section of the summary, which was taken up for discussion early in the approval process, achieved a smooth convergence between the authors and country delegates.
On the flip side, the international cooperation section was much shortened, simplified and seemingly stripped of controversy. This section had much less time allowed for discussion and was examined in a contentious atmosphere after the removal of several figures involving country groupings.
Fellow IPCC author Michael Oppenheimer, the Albert G. Milbank Professor of Geosciences and International Affairs in the Woodrow Wilson School and Department of Geosciences, who was not an author of the Science article, fully supported its position.
"IPCC, and attempts to solve the climate problem, would benefit immensely from a strengthening of the science-policy interface," Oppenheimer said. "Proposals to completely separate the science and policy functions are simply wrong-headed and self-defeating. This collaboration is what makes IPCC unique and uniquely effective"
"Seemingly technical choices can crystallize into value-laden political conclusions, particularly given tight word and time limits," said Fleurbaey. "It is more productive for authors to be aware of the varying political implications and factor these into their representations of data."
The review, "Political implications of data presentation," was published July 4 in Science.