An AAAS forum on climate change, held this week in Washington, DC illustrates, in microcosm just about everything that is wrong with the climate change debate. The forum was put together ostensibly to present scientific perspectives on climate change. Thus, there were papers presented with titles such as “Complexities in the Temperature Signal: Aerosols and Trace Gases,” “Polar Ice, Melting, and Sea Level Change,” and “What Earlier Warm Periods Can Tell Us About the One We’re In”

But let’s be honest — the public, the media, and policy makers care about climate science not because it is interesting (which it is) but because it has significance for how we think about the nature of the climate problem and the scope of potential options in response. Thus, the forum inevitably saw a sort of “mission creep” from science to politics, e.g., as reflected in media coverage.

Consequently, we see statements like the following (as reported here from scientists who participate in the panel:

“You hope that somehow people will understand that we have got to do something now,” Joyce Penner, an atmospheric scientist at the University of Michigan, said in an interview. “Some people get it — some people are driving hybrids. But there is a problem with the American public.”

“The models … are good enough to tell us we ought to be starting now to do what we can to reduce emissions,” said Michael Oppenheimer, a professor of environmental science at Princeton University.

“In this country it depends a lot on what happens in the next election,” said geochemist Daniel Schrag of Harvard University. “I don’t think we can expect to change the minds of this administration in the next couple of months.”

As I have frequently written (for recent articles see this and this), climate change is a problem worth our attention and both mitigation and adaptation policies are worth considering and adopting. But we are deluding ourselves (and ignoring volumes of solid research on science and decision making) if we think that climate science or climate models can tell us to (a) drive hybrids (or not), (b) reduce emissions (or not), or (c) vote against George Bush (or not). Each of these actions may indeed be very good ideas, but individuals will think them good (or bad) ideas because of the values associated with driving a hybrid, reducing emissions, or voting against President Bush. Climate science can help to inform us about the consequences of alternative courses of action; It cannot tell us how to value those different alternatives.

Science in general and models in particular are simply incapable of dictating values or expectations. As Dan Sarewitz has written:

“What we do, or don’t do, about global warming (or stem cell research, regulation of toxic chemicals, protection of endangered species . . .) will be a reflection of how we choose among competing values, and making such choices is not the job of science, but of democratic politics. Science can alert us to problems, and can help us understand how to achieve our goals once we have decided them; but the goals themselves can emerge only from a political process in which science should have no special privilege… [no one] want[s] to give up on the pretense that these controversies are about science. To do so would be to abandon the high ground created when one can claim to have “the facts” on one’s side. The resulting charade, where everyone pretends that science can save us from politics, undermines science by turning it into nothing more than ammunition for opposing ideologies. Even more dangerously, it damages democracy by concealing what is really at stake – our values and our interests – behind a veil of technical language and competing expertise.”

It is one thing when partisan groups such as the Marshall Institute arguably politicizes science as a tool of advocacy in support of their special interests. It is another thing altogether when a purportedly non-political professional association like the AAAS, ostensibly working for common interests, legitimizes the practice.