Correspondence | Published:

Climate: open review may ease acceptance of report

Naturevolume 441page406 (2006) | Download Citation



As executive director of the Office of the US Global Change Research Program from 1993 to 1997, I was responsible in 1995 for urging adoption of the national review process of the IPCC report that is questioned in your News story “US posts sensitive climate report for public comment” (Nature 441, 6–7; 2006).

The IPCC has always used a multi-stage review process. The first review is by nominated technical experts. In the second review, however, copies of the report are also sent to governments and all non-governmental organizations registered with the IPCC. In this round, the governments can each choose their own review process. What led to the US decision for open review was a query from one industry association that was interested in the environment but had not been sending a representative to IPCC plenary meetings. It asked why it was denied a chance to review the report when similar groups with a clear advocacy position were not. We could think of no acceptable answer. If all the world's nations and hundreds of scientists and non-governmental groups could review the report, how could we say some groups could not?

In response, at my urging, the US government agreed to a process whereby notice of the report's availability would be published in the Federal Register, calling for comments. This has been the practice ever since, and initial fears that it would be abused, for example, by large numbers of coordinated pleadings, have not materialized.

We did insist that those submitting comments identify themselves: a step we hoped would encourage careful and responsible presentation of comments. But we decided that what would matter was the merit of the comment, not its origin. Each comment was evaluated by an interagency team of government programme managers with interests and expertise in the area under consideration. In general, most comments were accepted: industry reviewers often had special insight into issues relating to emissions and approaches to mitigation; environmental-group reviewers had views on ecosystem behaviour and related pollution issues; and public reviewers had views on the clarity of presentation, or the significance or uncertainty of the findings. There were some off-the-mark and gratuitous comments, but not many, and these were filtered out by the interagency review process.

My impression was that the process worked well through the second and third IPCC assessments, and that the comments submitted helped to improve the overall quality of the assessments. There were instances of a strong difference of opinion within the expert community. But in all cases, through communication between authors and reviewers, we were able to facilitate a positive outcome. There was a sense that all legitimate perspectives (those written up in peer-reviewed or other equivalent form) had been fairly considered.

I have not been part of the government's planning or conduct of this review round. I am impressed, however, by their commitment to continuing the open approach. Let's not fear getting comments; in my opinion, promoting wide involvement in the review process, where questions can be clarified, has much greater potential for winning general acceptance of the findings than springing results on uninformed parties through some media blitz at the end of the process.

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  1. Climate Institute, 1785 Massachusetts Avenue NW, 20036, Washington DC, USA

    • Michael MacCracken


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