The credibility factor

ResearchBlogging.orgThe more peer-reviewed papers a climatologist has published and the more often those papers are cited, the more likely it is that the researcher supports the science underpinning anthropogenic climate change (ACC). That's the conclusion of a paper published this week in the Proceedings of the National Academy of Sciences.

This comes as absolutely no surprise to anyone working in or following the field. But scientists like to put numbers to things, and the paper, "Expert credibility in climate change" does a pretty good job of doing just that.

i-21964cd4952b706dd6fc1baa71d94c6b-prallgraph.jpgThere's a marvelous, interactive, graphical illustration of the data at Jim Prall's website. (Click on the screen capture at right to get there.) Here's the bottom line:

...97-98% of the climate researchers most actively publishing in the field support the tenets of ACC outlined by the Intergovernmental Panel on Climate Change, and (ii) the relative climate expertise and scientific prominence of the researchers unconvinced of ACC are substantially below that of the convinced researchers.

There are problems with oversimplifying the spectrum of opinion in any scientific subject. The four authors of the study, William R. L. Anderegg (Stanford), James W. Prall (U of Toronto), Jacob Harold (William and Flora Hewlett Foundation), and Stephen H. Schneider (Stanford), divided climate researchers into two groups, those convinced by the evidence that fossil-fuel emissions are heating the planet, and those unconvinced. The convinced group had far more papers and citations to their name than the unconvinced.

Some critics complain that this kind of dichotomy is misleading. Roger Pielke Jr. of the University of Colorado told the journal Science that "By putting scientists into two categories which do not reflect the subtleties of the debate, ... this paper simply reinforces the pathological politicization of climate science in policy debate." There's some merit in that argument, but the paper's conclusions address a critical problem: the insistence of many mainstream news outlets to treat each side with undeservedly equal levels of respect. As Schneider et al. write:

Despite media tendencies to present both sides in ACC debates, which can contribute to continued public misunderstanding regarding ACC, not all climate researchers are equal in scientific credibility and expertise in the climate system. This extensive analysis of the mainstream versus skeptical/contrarian researchers suggests a strong role for considering expert credibility in the relative weight of and attention to these groups of researchers in future discussions in media, policy, and public forums regarding anthropogenic climate change.

Among the paper's strengths are the depth of analyses of the numbers. As Leo Hickman blogs at The Independent, you'd think that the numbers might be skewed in favor of older researchers, who have had more time to publish and be cited, if all else was equal.

From the ~60% of researchers where year of PhD. was available, mean year of receiving a PhD. for UE [unconvinced by the evidence] researchers was 1977, versus 1987 for CE [convinced by the evidence] researchers, implying that UE researchers should have on average more publications due to an age-effect alone.

The fact that the numbers do not show such a bias only bolster the conclusion that

these methods are likely to provide a reasonable estimate of the preeminent researchers in each group and are useful in comparing the relative expertise and prominence between CE and UE groups

Hickman asks if this may be an example of "retired man syndrome" when "scientists who have already seen the best days of their career pass them by develop a contrarian view in an attempt to seek validation and court attention?" That would certainly fit the bill for Freeman Dyson, for one, who despite not publishing anything even remotely close to the subject for decades, sees fit to challenge the experts now actively working in the field.

At the very least, it would be a good idea for a reporter preparing a story on climate change to check Prall's database before quoting an unfamiliar climatologist.


Anderegg, W., Prall, J., Harold, J., & Schneider, S. (2010). Expert credibility in climate change Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.1003187107

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I checked out the Prall database. 'Contrarian' number 6 is Will Happer, whom it lists as a 'particle physicist'. Will is most definitely not a particle physicist; he's an atomic/molecular physicist, which is very different (ask a physicist, if you don't believe me). The database says his field is not climate related. LOL! Strike 1.

Then I looked at the PNAS paper. The central premise of the paper is that to be credible in climate science, one must publish in climate science. Fair enough. The PNAS paper is categorized as 'social science'. The four authors are a biologist, an electrical engineer, a 'BA from Duke University, where he designed his own major in ethics and intellectual history, and earned an MBA from Stanford's Graduate School of Business', and Schneider, a climate scientist. So none of the authors of this paper in 'social science' has any discernible credentials in social science. Strike 2, but 100% on the complete-obliviousness-to-irony meter.

And, of course, the paper itself was submitted by Schneider to PNAS, meaning that he himself chose the so-called 'peer-reviewers', and handled the refereeing of his own 'paper'.

Strike out.

Careful Mr. Harbison. From the tone of you arguments, one might think your criticisms were primarily ideological.

For instance, I hope you realize that your second point is complete bullshit.

Another contributing factor regarding the volume of work is obviously that the "contrarian" point of view makes no money. Not to mention skepticism is so very unhip and avoided by most scientific journals. I realy get a charge out of the alarmist overexamination of the skeptics and how they pay so little attention to the travesty science is enduring under a politically driven green agenda. What keeps me smiling is I know it is not going to get warmer. I have studied the past and can predict the future. One word of advice, invest in fuel oil.

Gerard, if I can elaborate on Tamarron's admittedly insulting point, the reason your second idea doesn't make sense is that the authors of the paper are not trying to advocate a complete sea change in the field of social science. There'd be nothing wrong with say, a physicist writing about climate change and there's nothing to say that his/her contributions wouldn't be useful. On the other hand, if said physicist is insisting that his physical model is correct, and all the actual climate scientists are wrong, I'd be a lot more skeptical of what they're claiming. As far as your irony meter is concerned, perhaps you shouldn't buy the Wal-Mart brand, I'm not surprised it detects things that aren't irony. Here's a tip, if it goes off when you play that shitty Alanis Morrisette song, then it's not sensitive enough and is reacting to things that most certainly are not ironic.

Don't know what to say about the physicist thing, but unless you have some facts that would lead me to believe the peer reviewers were on the take or incompetent, your accusation about them is groundless and is right up there with the East Anglia "controversy." Having an association with the author of the paper is hardly grounds for questioning it, unless you're the kind of wag who thinks any pharmaceutical company-funded study is corrupt and worthless.

Tamarron, while I can appreciate your disagreement, save the "bullshit" calls for people like Gator, they deserve it much more. The "politically driven green agenda," "I can predict the future," "the contrarian view makes no money." Now THAT is some steaming bullshit that's not even worth debunking, although if Gator's feeling nice he should give us the next winning lottery numbers, seeing as how he's the next incarnation of Nostradumbass.

By Rob Monkey (not verified) on 23 Jun 2010 #permalink