STEVE INSKEEP, HOST:
OK, another major U.N. body is meeting in Stockholm. The United Nations Intergovernmental Panel on Climate Change, the world's most widely recognized authority on global warming, is set to release its latest big report on the science of climate change.
Scientists and politicians are gathered together this week to finalize that report. It's their fifth assessment. Over the years, this process has been important for putting climate change on the world's agenda. But some scientists are wondering whether these intensive reviews still make any sense. NPR's Richard Harris reports.
RICHARD HARRIS, BYLINE: The first IPCC report came out in 1990, just a few years before nations of the world agreed to a treaty that said human beings should avoid damaging the Earth's atmosphere. Michael Oppenheimer at Princeton says the group's second assessment, in 1995, warned that humans could already be affecting the climate, and that built political momentum for action.
MICHAEL OPPENHEIMER: That had a big effect in helping governments focus on the need for the Kyoto Protocol.
HARRIS: That was an agreement that called on the world's richest nations to start reining in their carbon dioxide emissions. Reports since then have built increasingly stronger and stronger cases that climate change is real, caused mostly by human beings, and could cause real problems down the line. The IPCC reached its pinnacle in 2007, when it shared the Nobel Peace Prize with Al Gore for bringing this issue to the world's attention. But the science is so well-established, what now?
OPPENHEIMER: There is a certain view now - and I tend to agree with it - that repeating the same story again and simply refining the findings in a way which makes marginal improvements isn't all that helpful.
HARRIS: Particularly since it consumes a huge amount of time of the volunteer scientists who might otherwise be out there doing more science. And Oppenheimer says this as a scientist who has been involved in the IPCC process since the beginning. He's spearheading a chapter in the upcoming report. Part of the problem is it's become more time-consuming and complicated to produce these reports. That's because it turns out that the 2007 report contained some embarrassing errors that they were reluctant to correct.
ROGER PIELKE JR.: The IPCC, somewhere along the line, became very much wrapped up in the politics of the climate debate.
HARRIS: Roger Pielke, Jr. is an environmental scientist at the University of Colorado in Boulder. He says the scientists got so defensive in the last report, that they didn't do an honest job of characterizing all the science.
PIELKE: The IPCC implied that increasing temperatures were causing increasing disaster losses. And the scientific literature just doesn't support that.
HARRIS: Pielke says the authors were too eager to show a link between catastrophes and climate change. But he says the IPCC has corrected that in a supplemental report issued last year.
PIELKE: It had a special report on extreme events that seems to have gotten it back on track.
HARRIS: Part of that adjustment involves a much more comprehensive review process, which has been put to use in this latest report. In addition to the hundreds of authors, there are also hundreds of expert reviewers who generate tens of thousands of comments about the reports. Michael Oppenheimer says authors like him have to respond to each one of these. Pielke and Oppenheimer both suggest that, looking forward, the IPCC might better spend its time doing more targeted reports that take on a narrowly defined issue, like the one that looked at extreme weather events.
OPPENHEIMER: That kind of report that's very focused can be done within perhaps as little as a year, will be very timely, won't be out of date when it hits the streets, and yet can be subject to the same kind of thorough peer review, that that's what the direction that IPCC should be headed.
HARRIS: But that's something to think about for next time. The current mega-report is just about done. A summary of the first part comes out on Friday, and parts two and three are due out in the spring. Richard Harris, NPR News.
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