The IPCC process and public opinion
I understand that the IPCC [Intergovernmental Panel on Climate Change] uses as a source of information only papers already published in peer-reviewed journals. Peer-reviewing ensures that papers do not wander too far from prevailing opinion without a very good reason. This maintains scientific quality, but also ensures that authors express themselves temperately and conservatively, regardless of how alarmed they may personally be by their findings. The process also adds to publication delays which may amount to some years in some journals. The result is that IPCC reports are both conservative and a year or two out of date on publication. The Copenhagen conference, on the other hand, seems to have been a discussion among working scientists, talking in real-time about their recent findings and current concerns. The thousands of peer-reviewed papers they will later publish will influence future IPCC reports, but there is a case for greater urgency in filling or at least highlighting knowledge gaps, and in identifying dangerous new trends. The precautionary principle does not require scientific certainty, and we should be very precautionary about climate change since the stakes are so high. I welcome the enhanced public awareness and understanding of climate issues allowed by media coverage of Copenhagen. For it is ultimately public opinion that will drive real political inventiveness.
Julian Caldecott, BBC web-site, 17 March 2009.