How not to Keep Climate Science Separate from Politics

A group of top-flight scientists have a letter (subs. req’d) in the new issue of Science (h/t: Joe Romm, who likes the letter a lot more than I do) calling for

“the science community to develop, implement, and sustain an independent initiative with a singular mandate: to actively and effectively share information about climate change risks and potential solutions with the public, particularly decision-makers in the public, private, and nonprofit sectors.”

It’s a laudable project, and I’m inclined to be supportive, particularly given this admonition from the authors:

“[The initiative] should not advocate specific policy decisions; good decision making involves weighing the best available information with the values of the decisionmakers and those affected by the decisions.”

That’s why I find the opening line of the leter absolutely ridiculous:

“According to broad international agreement, a global warming increase beyond 2°C is unacceptable.”

Pardon? This is a purely political statement. The authors’ own letter explains why: to settle on a two degree target, rather than something higher or lower, one must integrate science with an assessment of values. Indeed while all the other citations in the letter point to scientific papers or statements by scientific societies, the reference for this particular claim points to a G8 communique (PDF). What’s worse, the sentence is totally unnecessary. There is nothing else in the letter that rests on it; it could have been left out with no loss whatsoever.

I know that some readers will object, pointing out that the authors don’t actually say that an increase beyond 2°C is unacceptable; they simply say that there’s “broad international agreement” on that point. But these are smart people, and they know how their letter will be read.  (I know several of the authors, and have great respect for them.) This is a group of scientists, writing in a scientific journal, clearly deploying their scientific authority. They do not even bother to add to word “political” in front of “agreement”. They ought to understand that they themselves are mixing value judgments with science, or at least encouraging others to do so in a very specific way. That may be fine, in principle, but it seems to be the opposite of their declared objective.

Let me close with one more quote from the letter:

“In the face of efforts to undermine public confidence in science, [the initiative] must become a trusted broker of unbiased information for people on all sides of the issue.”

I’m all for that. Those who are involved in the initiative will need to be far more careful to keep value judgments out of their communications if they’re going to succeed.