Clearly, at the outset, the early IPCC reports played an important role showing that there was a high degree of consensus around the reality and basic science of human-induced climate change. It was important to show that, despite a few climate-science deniers, the fundamental science was well-accepted by the mainstream scientific community.
But can anybody point to any important positive outcomes resulting from the IPCC AR4 process? [AR4 is shorthand for the panel's fourth assessment, which was published in 2007.] Is there reason to expect a greater positive impact from the IPCC AR5 process? [This is the forthcoming fifth assessment of climate science and policies, coming in 2013 and 2014]
I am all for scientific reviews and assessments, and I think the multi-model comparisons reviewed by the IPCC have been especially useful. However, it is not clear how much additional benefit there is to having a huge bureaucratic scientific review effort under UN auspices...
(As an aside, I recently resigned as a lead author of an IPCC AR5 chapter simply because I felt I had more effective ways of using the limited amount of time that I have to engage in scientific activities. My resignation was made possible because I believe that the chapter team that I was part of was on the right track and doing an excellent job without my contribution. Had I had a scientific criticism of my chapter team, you can be assured that I would have stayed involved. So, my resignation was a vote of confidence in my scientific peers, not a critique. It is just not clear to me that, at this point, working on IPCC chapters is the most effective use of my time.
About Ken Caldeira
Caldeira is a lead author for the upcoming IPCC AR5 report and was coordinating lead author of the oceans chapter for the 2005 IPCC report on Carbon Capture and Storage. In 2010, Caldeira was elected Fellow of the American Geophysical Union.He was a co-author of the 2010 US National Academy America's Climate Choices report
KENNETH G. CALDEIRA joined the Laboratory's Atmospheric Chemistry Group as a physicist in 1993 and has been an environmental scientist in the Climate System Modeling Group since 1995. He received his Ph.D. and M.S. in atmospheric science from New York University in 1991 and 1988 and his B.A. in philosophy from Rutgers University in 1978. He also served as a postdoc at Pennsylvania State University's Earth System Science Center. Caldeira has published many papers, for example, on climate stability of early Earth and the global carbon cycle as it has been affected by human activity over millions of years.