Why science and politics don't mix

But you’d be hard-pressed to argue that all parts of the climate-science community, for instance, had nurtured opportunities for the falsification of their own beliefs. The e-mails published during the Climategate scandal suggest that was not a priority. Groupthink, getting with the program and extreme impatience with dissent seem more to the fore in some climate-science quarters than zealous self-criticism.

Climate science, a far-flung family of loosely related disciplines, is unusual because it has become closely aligned with a set of costly and controversial policy proposals. This political orientation raises a question: Which comes first — the science of climate or the art of persuasion?

Many climate scientists believe global warming requires urgent measures to cut greenhouse-gas emissions. They look despairingly at governments unable or unwilling to respond and campaign all the more aggressively. They have a case (I’m for a gradually increasing carbon tax, if you’re wondering), but their standing as advocates and activists has undermined their authority as disinterested scientists. The Intergovernmental Panel on Climate Change, which will release its fifth assessment report on global warming next year, is likewise seen by many as an advocacy organization rather than a neutral compiler of scientific evidence. This has done great harm: The scientist-advocates overreached and diminished their own effectiveness.

What to do about climate change is indeed a political question. Good science, along with good economics, is needed to inform the political judgment, but to claim that the science is settled and that the right policy is dictated by undisputed facts is false. The science isn’t settled, and even if it were, it wouldn’t dictate the policy. Voters know this, which is why the tactic didn’t work. Science, for its own sake and everybody else’s, should keep a cautious distance from politics.