25 June 2010

Levi Gets the Last Word on PNAS

Writing at Slate, Michael Levi cogently summarizes the broader issues associated with the PNAS paper.
The evidence that we are running dangerous risks with the climate is overwhelming. In their zeal to convince the public of this fact, environmental advocates sometimes hype sensational studies and predictions that rest on weak or ambiguous logic. Every time they do, their opponents have a field day.

This week the greens have played right into that trap. . . .

he paper, entitled "Expert credibility in climate change," was published Monday in the Proceedings of the National Academy of Sciences (PNAS). Within hours, a host of progressive and environmentalist groups were loudly touting its conclusions, and sympathetic articles appeared in USA Today, The New York Times, and Time. On Wednesday morning, the White House drove the message home with an official tweet: "Scientists agree on climate change...the few that don't? not cream of crop." . . .

All of this would be academic quibbling if it wasn't so consequential. The authors of the paper are right that the world is running dangerous risks with the climate system. They are right to be angry at those who claim that climate change is a hoax, and at those in the media who give them a platform to confuse the public. But the way to confront those skeptics is to show that they're wrong—as many dedicated climate scientists have done, again and again. Hyping this paper, instead, simply reinforces the dangerous perception that climate activists will credulously push any news that might further their case. For those who care about this issue, that's tragic.
What is more damaging to efforts to implement policies to accelerate decarbonization of the global economy, climate skeptics, or the clumsy efforts to delegitimze them?

Levi is right on the mark when he writes:
. . . the advocates have used bad social science to show that the science of climate change is sound.
And that is a fitting last word on PNAS, at least for this blog. But feel free to continue the discussion in the comments if you'd like. I'm returning to more important topics, like energy policy and soccer ;-)


  1. Nigel Calder offers an other, last, word.


    ¨Anderregg et al. claim that scientists convinced about man-made global warming are cleverer and better respected, as well as much more numerous, than scientists who are unconvinced.

    Now I'll say that it's scary but not surprising that the National Academy of Sciences should permit a division of experts into an ingroup and an outgroup, and an evaluation of them by arbitrary tests that have nothing whatever to do with the inherent substance or merit of their research.¨

  2. It is interesting to consider why, if CAGW is so true and settled, so many of its believers and promoters have to resort to untruths and misleading tactics to explain it.
    One obvious answer is that perhaps CAGW is not nearly as true and settled as its adherents frantically claim.

  3. "The evidence that we are running dangerous risks with the climate is overwhelming." Even if one doesn't agree with that statement, Michael Levi is right in saying that the clumsy efforts to marginalize global-warming "deniers" are counter-productive. Some would say, though, that such unfair tactics are being used precisely because the evidence for the "orthodox" position is not as "overwhelming" as he would have us believe.

  4. One of the lesser tidbits I learned in grad school: there is no science in social science.

  5. Anyone noted the irony that the PNAS authors accuse disgareeing scientists of 'dabbling' (in climate science) while they themselves are 'dabbling' (in social science)?

  6. And -- pray tell -- just what is the "overwhelming" evidence that climate risks are dangerous? For once, please tell us and lay it out so we can see it and critique it, rather than simply telling us how overwhelming it is. Papal infallibility does not work in science.

  7. Roger,
    What a relief. I had been warming up to give you a hard time for not noting "running dangerous risks" and then pjoenotes commented and you expressed a view with which I concur.

    "Running a risk" suggests that we have it within our power to do or not do things which will prevent or avoid something the climate might do.

    Wouldn't it be neat if he identified the climate condition we are risking and stated the measures we might take.

    If no measures can avoid or prevent the calamity then I don't see how there can be a risk.

  8. “The evidence that we are running dangerous risks with the climate is overwhelming.”
    Levi is merely exercising the classic “arguments with no arguments”. Its an attempt to present a notion as axiomatic.

  9. The greatest risk is that the world's leaders will not have reliable scientific information on which to base sound decisions because NAS has placed federal funding ahead of basic scientific principles. In my own area of research, the greatest risk is that decisions will be based on misinformation about the Sun ["Earth's heat source - the Sun", Energy & Environment 20 (2009) 131-144] http://arxiv.org/pdf/0905.0704

    With kind regards,
    Oliver K. Manuel
    Former NASA Principal
    Investigator for Apollo

  10. Dr. Manuel said: "The greatest risk is that the world's leaders will not have reliable scientific information on which to base sound decisions ...."

    This seems very likely, or if they do have it, they won't recognize it as such, or understand it.

    I suggest we rely on unintended consequences of whatever action or inaction they take not necessarily being bad; maybe good.

    Maureen Dowd's (NYT) attribution to Speaker Pelosi of a panoply of CAGW misinformation suggests the view above as a reasonable protection for one's sanity.