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Tuesday, June 22, 2010

Anderegg, Prall, Harold, Schneider, PNAS (2010), Expert credibility in climate change

Proceedings of the National Academy of Sciences,

Expert credibility in climate change

William R. L. Anderegg, James W. Prall, Jacob Harold and Stephen H. Schneider


Although preliminary estimates from published literature and expert surveys suggest striking agreement among climate scientists on the tenets of anthropogenic climate change (ACC), the American public expresses substantial doubt about both the anthropogenic cause and the level of scientific agreement underpinning ACC. A broad analysis of the climate scientist community itself, the distribution of credibility of dissenting researchers relative to agreeing researchers, and the level of agreement among top climate experts has not been conducted and would inform future ACC discussions. Here, we use an extensive dataset of 1,372 climate researchers and their publication and citation data to show that: (i) 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. 


Pete Ridley said...

This is a comment that I have just posted on another blog ( is continung to push the highly suspect claims in this paper.

Mike, on 16th Dec. @ 00:53:42 you made reference to the PNAS paper “Expert credibility in climate change” ( was written by Stephen H Schneider, a devout “disciple *”. This same “disciple” is on record ( as saying “On the one hand, as scientists we are ethically bound to the scientific method, in effect promising to tell the truth, the whole truth, and nothing but — which means that we must include all the doubts, the caveats, the ifs, ands, and buts. On the other hand, we are not just scientists but human beings as well. And like most people we'd like to see the world a better place, which in this context translates into our working to reduce the risk of potentially disastrous climatic change. To do that we need to get some broadbased support, to capture the public's imagination. That, of course, entails getting loads of media coverage. So we have to offer up scary scenarios, make simplified, dramatic statements, and make little mention of any doubts we might have. This 'double ethical bind' we frequently find ourselves in cannot be solved by any formula. Each of us has to decide what the right balance is between being effective and being honest. I hope that means being both. (Quoted in Discover, pp. 45–48, Oct. 1989. For the original, together with Schneider's commentary on its misrepresentation, see also American Physical Society, APS News August/September 1996.[6])" ( but see also

The pronouncements of any scientist who only “hopes” that scientists “must” tell the truth have to be regarded with scepticism. That is not “denial *”, merely a sensible application of caution.

There is no convincing scientific evidence supporting the doctrine, only speculations and estimations merged with some scientific evidence that our use of fossil fuels could have caused a proportion of what is claimed to have been an increase in mean global temperature of about 1C during the past 150 years. This has all been packaged together to produce some wonderful propaganda in support of agenda that have nothing to do with taking over nature’s job of controlling global climates. The real agenda are:
- redistribution of wealth from developed to underdeveloped economies,
- establishment of a framework for global government,
- enhancement of the finances of a privileged few.
Evidence of the first two can be found in the draft and final agreements coming out of the UN’s COP15 “caper in Copenhagen and its COP16 “conspiracy in Cancun”. More will be available after what is hoped will be the final COP17 “debacle in Durban”.

* - of the doctrine that our continuing use of fossil fuels is leading to catastrophic changes in the different global climates (

Best regards, Petye Ridley

Pete Ridley said...

I have posted a comment about the highly suspect claims in this paper by Schneider about 97-98% of scientists supporting the doctrine that our continuing use of fossil fuels is leading to catastrophic changes to the different global climates (see Kopen's classificartion).

I tried to post the comment here but I think there were too m,any links in it.

My comment appears on the Watching the Deniers blog "Fox News: their idea of fair and balanced .. " thread.

I'll post the link separately.

Best regards, Pete Ridley

Pete Ridley said...

THe link (witout the https://) is: