BUSTED: Tol takes on Cook's '97% consensus' claim with a re-analysis, showing the claim is 'unfounded'

97_percent_bustedA new paper by Dr. Richard Tol published today in ScienceDirect, journal of Energy Policy, shows that the Cook et al. paper claiming that there is a 97% consensus among scientists is not just impossible to reproduce (since Cook is withholding data) but a veritable statistical train wreck rife with bias, classification errors, poor data quality, and inconsistency in the ratings process. The full paper is available below.

Quantifying the consensus on anthropogenic global warming in the literature: A re-analysis

Richard S.J. Tol dx.doi.org/10.1016/j.enpol.2014.04.045


A claim has been that 97% of the scientific literature endorses anthropogenic climate change (Cook et al., 2013. Environ. Res. Lett. 8, 024024). This claim, frequently repeated in debates about climate policy, does not stand. A trend in composition is mistaken for a trend in endorsement. Reported results are inconsistent and biased. The sample is not representative and contains many irrelevant papers. Overall, data quality is low. Cook׳s validation test shows that the data are invalid. Data disclosure is incomplete so that key results cannot be reproduced or tested.

Conclusion and policy implications

The conclusions of Cook et al. are thus unfounded. There is no doubt in my mind that the literature on climate change overwhelmingly supports the hypothesis that climate change is caused by humans. I have very little reason to doubt that the consensus is indeed correct. Cook et al., however, failed to demonstrate this. Instead, they gave further cause to those who believe that climate researchers are secretive (as data were held back) and incompetent (as the analysis is flawed).

It will take decades or longer to reduce carbon dioxide emissions to zero—the only way to stabilize its atmospheric concentration. During that time, electoral fortunes will turn. Climate policy will not succeed unless it has broad societal support, at levels comparable to other public policies such as universal education or old-age support. Well-publicized but faulty analyses like the one by Cook et al. only help to further polarize the climate debate.

Full paper available in plain text here: http://www.sciencedirect.com/science/article/pii/S0301421514002821

And a PDF here: http://www.sciencedirect.com/science/article/pii/S0301421514002821/pdfft?md5=3ec2c68758ccd267c4c6c63bd5e7bb5a&pid=1-s2.0-S0301421514002821-main.pdf


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Sproing another leak in SS CAGW “Ship of Fools”

Marc Blank

It’s worse than we thought (is that even possible??)


So now we know why Nutty Dana is attacking Tol on the Guardian. No surprise.

Sweet Old Bob

Even though the “books were Cooked ” not a damn thing will happen to him ,except that he will probably gain prestege and be lauded . What a sorry state of affairs…..


There is no doubt in my mind that the literature on climate change overwhelmingly supports the hypothesis that climate change is caused by humans…


It’s never been about reducing CO2. It’s always been about power. Always.
–Andrew, @LawSelfDefense


The only “veritable statistical train wreck rife with bias… poor data quality” is Tol’s bizarre paper.
Can we get you on record, Anthony, endorsing the math behind it? I know that posting it here is an implicit endorsement of Tol’s mangled effort, but could you step up and say outright how impressed you are? Please?
You are going to be embarrassed for having highlighted this. But that’s ok. Nothing we haven’t seen you do many times before.
By the way, Anthony, those extra ~ 300 papers Tol “found” rejecting the consensus. Care to point us to a few?
REPLY: Here’s the thing, I don’t deal with punks that demand that I do specific things who are too timid to use their own names. Bug off – Anthony

Dave N

Cue alarmists pronouncing “ScienceDirect” as a “denier” journal in 3… 2… 1…

Dave N

Hmmm.. The link to the article is broken, or the ScienceDirect site is having issues?

Steve Oregon

Why would Tol (or anyone else_ have “no doubt in their mind” when they acknowledge some have resorted to such “Well-publicized but faulty analyses”?
It’s not like Cook’s work is the only cooked up AGW stunt.
Is Cook’s stunt fraud?


How many times does that paper have to be disproved?
Not that it matters, it is ingrained into the public consciousness and no amount of disproof will dispel the idea. None. You’re trying to fight emotion with fact. You’ll lose every time. EVERY time.
As Hamilton said, “Your people, sir, is nothing but a great beast!” meaning that the ‘public’ is subject to emotions more so than fact.

Latitude says:
June 4, 2014 at 3:12 pm
There is no doubt in my mind that the literature on climate change overwhelmingly supports the hypothesis that climate change is caused by humans…
Of course. The funding for research overwhelmingly supports research that supports the hypothesis, so the literature that flows from said funding will also support the hypothesis. It is just like tobacco in the 1950’s. The funding was all in support of tobacco being harmless, so that is what the research showed. If you show otherwise, you don’t get any more funding. Climate research today is at about the same place that tobacco research was about 1960. The dollars being thrown at it are huge compared to the tobacco scam, so it will take more than a surgeon general’s report to begin a shift.

Rick K

“A new paper by Dr. Richard Tol published today in ScienceDirect … shows that the Cook et al. paper claiming that there is a 97% consensus among scientists is not just impossible to reproduce… but a veritable statistical train wreck rife with bias, classification errors, poor data quality, and inconsistency in the ratings process.”
In other words, ‘ready for prime time climate science’.

From the Conclusion: “climate change is caused by humans”.
Shouldn’t that be, “SOME climate change is caused by humans?”

(A) Welcome to the big leagues, boys.
(B) However, I hope Dr. Tol himself, despite risking funding hits, will eventually stop implying a need to cut emissions drastically and thus ruinously and eventually genocidally, given that the Jesus paper has finally arrived that actually measured the overall greenhouse effect with physical feedbacks and found it to be miniscule despite high theoretical forcing and supercomputer model positive feedbacks:
“Tiny warming of residual anthropogenic CO2”
Abstract: “The residual fraction of anthropogenic CO2 emissions which has not been captured by carbon sinks and remains in the atmosphere, is estimated by two independent experimental methods which support each other: the 13C/12C ratio and the temperature-independent fraction of d(CO2)/dt on a yearly scale after subtraction of annual fluctuations the amplitude ratio of which reaches a factor as large as 7. The anthropogenic fraction is then used to evaluate the additional warming by analysis of its spectral contribution to the outgoing long-wavelength radiation (OLR) measured by infrared spectrometers embarked in satellites looking down. The anthropogenic CO2 additional warming extrapolated in 2100 is found lower than 0.1°C in the absence of feedbacks. The global temperature data are fitted with an oscillation of period 60 years added to a linear contribution. The data which support the 60-year cycle are summarized, in particular sea surface temperatures and sea level rise measured either by tide gauge or by satellite altimetry. The tiny anthropogenic warming appears consistent with the absence of any detectable change of slope of the 130-year-long linear contribution to the temperature data before and after the onset of large CO2 emissions.”
In this case it’s delightfully devilish for Dr. Tol to toe the line completely, to have maximum impact *within* climate science, helping to reform it, and Dr. Tol is after all not a physical scientist but a econometrician who is an expert on applying statistics, mathematics and computational methods in economic theory. So he may not have experienced the sense of jaw dropping shock I did when as an experienced laboratory researcher I started reading the output of climate “science” and noticed that no, they were simply not following the scientific method of tasking themselves with rooting out errors in their own work, at all, nor in their peer review of papers.
(C) When Dr. Tol asserts, “I have very little reason to doubt that the consensus is indeed correct.” then I must point out that the scam nature of IPCC level “science” revolves around a hockey stick team that to this day is ramping *up* the brazenness of the fraud rather than cleaning house since, really, they are themselves the only housekeepers so far, and their Soviet worthy lies now stand fully exposed as of their latest 2013 “super hockey stick”:
After recognizing this undeniable headline grabbing scam, I cannot take at face value his statement of having little reason to doubt a consensus, for any school child may now be savvy to the manipulated nature *of* that consensus, just looking at Willis Eschenbach’s plot of the Marcott 2013 input data. Here Dr. Tol is, after all, quite ironically claiming he has no reason to doubt the 97% consensus opinion, as he simultaneously debunks that such a consensus exists at all, even in climate science, and as any economist knows best of all, you can’t have your cake and eat it too.


Regarding “It will take decades or longer to reduce carbon dioxide emissions to zero—the only way to stabilize its atmospheric concentration.”
It might be better to say:
“It will take decades to centuries to drastically reduce human technology based sources of CO2 emissions (we still need to breathe, don’t we?) but since these emissions are only about 3 to 5 % of all emissions, this will only represent a 3 to 5% reduction of CO2 entering the atmosphere. This has little bearing on the stabilization of atmospheric concentration, since natural sources of CO2 can overwhelm those of human origin”


Gee, I hope someone is archiving this post so it doesn’t quietly disappear!
Everyone here ok with the “sophisticated” math that Dr. Tol is asking you to accept? ‘Cause you have looked under the covers and are persuaded it’s a rock solid piece of research?
Step up with Anthony and signal your personal endorsement of it! Don’t be shy! You know it to be true! Just step up and say something like “I have never seen such an elegant statistical analysis in my life!” or something like that.
Be bold and take a stand! Like, say, like Dr. Tol did in his conclusions!:
“There is no doubt in my mind that the literature on climate change overwhelmingly supports the hypothesis that climate change is caused by humans.”

On the one hand Tol debunks Cook et al, then immediately expresses the overt warmist case “There is no doubt in my mind that the literature on climate change overwhelmingly supports the hypothesis that climate change is caused by humans.” and “It will take decades or longer to reduce carbon dioxide emissions to zero—the only way to stabilize its atmospheric concentration.”. He might as well just agree with Cook’s consensus and have done with it.


subscribing to comments

Rud Istvan

Good for Tol. Steve Mc pleaded with me to withhold a second letter aimed at Cook, the first posted here and elsewhere previously. I replied that disagreed with Tol’s strategy, but would agree to a two week hold on tactics, despite what RT himself suggested. So, with more polish, will be fired off tomorrow. And perhaps JoNova, the Bish, and WUWT might take additional notice.

David Ball

Sorry, also wondering about the “polarization of the climate debate” comment? There has been only one side doing the polarizing.
This is also pointless as the POTUS quoted the 97% crap already and the damage has been done. This is just another distraction from the important questions that remain unanswered.
You earn a living doing this Dr. Tol?

Dana’s panties must be in a mighty knot today as the ASG has put their inability to reach consensus in writing for all the world to see! He’s going to be pissy about EVERYTHING until someone gives him a lolly or gets him down for a nap…..

Lost a post here somewhere….
Remember when there was a discussion thread in here about coming up with a “logo” or something to counteract that stupid red 97% dot of death? The one you posted here with BUSTED over it is PERFECT. Short. Understandable. TRUE. And will make the Hardly Boys wet their pants. It might even make them think TWICE before they develop any more shiny marketing, brainwashing widgets. I won’t hold my breath…but BUSTED can be applied to all of them and sent right back out.

rustneversleeps (June 4, 2014 at 3:52 pm): “Gee, I hope someone is archiving this post so it doesn’t quietly disappear!”
Paper is paywalled for me. Did you read it for free? What exactly do you believe is wrong with it?


Still hopeful that some brave souls will step forward with direct comments (compliments even!) about Dr. Tol’s math that suggests the Cook et al (2013) paper suggests the consensus might be as low as 91%. You agree with his math?
(Of course, even though Dr. Tol makes some badly wrong assumptions that leads to his results going off the rails, he doesn’t even really believe his findings anyway. He’s on record saying:
Published papers that seek to test what caused the climate change over the last century and half, almost unanimously find that humans played a dominant role.
The consensus is of course in the high nineties.
but cut him some slack there, because at least he has the kahunas to try to do the math and try to challenge Cook. So I am specifically asking for your inisghts on how well he did his math. Just for the record. Thanks.)


Are the AGWers now eating their own? What a shame, and what a shock too.


@erik1skeptic – I referring to THIS post, the very one at WUWT which we are currently commenting on. That’s the one I hope is archived in case it quietly disappears.
As to what is wrong with Tol’s paper, I can think of about 24 errors right off the top of my head.
Even if you leave aside some of the quantitative errors – which no one seems to want to investigate here so far – he does things like cite sources that state the exact opposite of the case he is making. Example:
Tol says, discussing Cook(2013)’s raters: “Fatigue may have been a problem, with low data
quality as a result (Lyberg and Biemer 2008).”

But what, in fact, do Lyberg and Biemer (2008) actually say?
“The fatigue discussed by Lyberg and Biemer (2008) addresses fatigue in survey subjects, describing how subjects taking repeated surveys can affect data quality. The abstracts, which are the subjects of the rating process in C13, cannot demonstrate fatigue. The raters performed the function of a survey interviewer in the process of rating abstracts. When contacted, Dr. Biemer confirmed that interviewers exhibit increased proficiency over time. According to T14’s cited source, the effect of rating large numbers of abstracts would have the opposite effect to
that stated in T14.”

Anthony began by referring to a paper as “veritable statistical train wreck rife with bias, classification errors, poor data quality, and inconsistency”. That pretty much describes Dr. Tol’s paper. Which I hope stays up as well.
Have a good evening, all. I am going to watch the New York Rangers – L.A. Kings game, but may find time to visit.


> You agree with his math?
I haven’t seen Dr Tol’s maths yet so I neither agree nor disagree with it.


Following nikfromnewyork’s link to Mann’s face book page revealed an astonishing ignorance by one poster who quoted…”carbon sequestration in peat-lands may have had important climate cooling effects…” ??? What next, “carbon” sequestration in trees?!!

All the links (including dx.doi.org) go to the paywall at Science Direct. 🙁

Tanya Aardman

William Connelly is back as Rustneversleeps -IP analysis confirmed
[no, this is not WMC – mod]

Pamela Gray

The conclusions of Cook et al. are thus unfounded. There is no doubt in my mind that the literature on climate change overwhelmingly supports the hypothesis that climate change is caused by humans.
What a tangled up mess.
1. Tol says the conclusions of Cook et al are unfounded, and then in the very next sentence pretty much says he thinks they are right.
2. The debate is not and never was about IF human activity causes climate change. The debate is about how much and quantifying any harm that may result.
I haven’t seen the full paper as it is pay walled, but from the little I see here, this paper contradicts itself (see 1. above) and adds nothing to our understanding of endangerment, just some hand waving on the issue along with some references to the ability to reduce emissions to zero on some vague assumption that despite the lack of consensus discovered in Tol’s own paper, it still needs to be done.
Rather disappointed actually.

Jake J

I’m not inclined to pay $20 to read Tol’s paper. If someone knows how to get it for free, please say so.


Ok, TerryS,
That’s a good answer.
Anyone else here seen the math? Or are you just confident in your gut the paper must be right? Anthony, you seen the math? Any thoughts on it?
For now, here’s a little sanity check teaser just to see if what Tol is saying passing the smell test.
In his paper, Tol makes the claim that the fact that the two raters of each abstract in Cook et al’s study disagreed about 33% of the time. Disagreements were settled by a reconciliation process, and if the two raters still disagreed, it went to a third tie-breaker. Tol infers from this that were still be residual errors left after that first round of reconciliation. Fair enough, but at this point he goes all “oooh, look at me do math”-y on us, and performs some operations that magically take the number of papers rejecting the consensus in Cook’s study from 78 to 379. Just right out of thin air. He doesn’t tell what papers they might be, just that his test tells him that they *must* be there. This is how he “determines” that the “real” consensus is only about 91%.
Leaving aside the mistaken assumption that he makes in this test that sends him off the rails – and I will assure, there is a very big mistake on this one – does that even make sense to you? That he was able to inflate the number of abstracts rejecting the consensus by a factor of almost 5 just running some test after the fact???? Seriously???
And if it *does* make sense to you, then that means that there were, in fact 379/11,944 = 3.17% of ALL the abstracts in Cook’s study – including the no opinion ones – that rejecting the consensus. If that is the case then about 16 out of every 500 papers should reject the consensus. You think that is correct? You think that would verify Tol’s work? Go ahead. Prove it. All the tools available to do so quite easily are already freely available from Cook.
Guess what. I doubt anyone will try. But I further doubt that, if they do, that they will get anywhere near that result.
It’s nonsense.
REPLY: My advice: if you so strongly believe Cook’s paper is without fault, petition him to release all the data, and let’s replicate it. Otherwise your opinion is just noise in the face of Cook preventing science from doing replication.
Let us know when you’ve got that taken care of. – Anthony

Jake J

@ davidmhoffer, there’s nothing necessarily a “tangled up mess” in what you cited. Cook alleged that 97% of scientific papers he survey support the AGW hypothesis. Tol says he also supports the hypothesis, but that Cook’s paper is invalid. I don’t see any contradiction at all.

Gary Pearse

I commented on the last several times Tol busted cook’s paper. Tol gives this silly stuff more legs when it has pretty well eaten itself to death. Even the Australian Society of Geologists is well over 50% anti-CAGW and has overwhelmingly shut its zealous secretariat up over trying to issue a statement supporting CAGW. This even debunks your conclusion that Cook is right for the wrong reasons. Your even attracting bottom feeders like the climate jackal ”rustneversleeps” who himself is even surprised that there is still meat to be found on this carcass. Dr. Tol, please, we’re away ahead of you on this. Go debunk Piltdown man for a while for a break for all of us.

Jake J;
I don’t see any contradiction at all.
And I don’t see any difference between 97% and “overwhelmingly support”.

Crispin in Waterloo

@rustneversleeps says:
I noticed how you were so interested in shooting messengers that you not only lost the plot, you don’t seem to have a viable one. Are you really Connelly? I thot you had been ‘Wikki-connied’ here.
Wikki-connied: verb, transitive; (1) to ban from a Wikipedia section for displaying an excessive devotion to truth and facts; (2) to ban from scientific discussion select people (as revenge) who have been doing so to others without just cause, in particular on Wikipedia’s climate ‘science’ section. Origin: the well-documented behavior of one William Connelly, a one-time Wikipedia editor whose bias and venom ultimately led to the misinformation of credulous millions.

Pamela Gray

Having read the preprint now, I don’t see much in terms of standard scientific refutation. It seems filled with first person opinion as to methods but supports the conclusion. It’s almost like he is trying to imbue what was dead with Frankenstein-ish life. It’s ugly but it’s alive, says he.
The problem is that we are coming up to a majority of the common people who are now seeing catastrophic AGW as just that. Another attempt by some fool mad scientist to make something look real, and scary, that isn’t real or scary. My new name for catastrophic AGW: Al Grankenstein, in the flesh…er…rotting flesh. Tol is that mad scientist trying to make ugly walk again.

William Astley

In support of:
“It will take decades or longer to reduce carbon dioxide emissions to zero—the only way to stabilize its atmospheric concentration. During that time, electoral fortunes will turn. Climate policy will not succeed unless it has broad societal support, at levels comparable to other public policies such as universal education or old-age support.”
It will take a massive complete absolute worldwide change to nuclear power, along with draconian, fascistic enforced restrictions (population control, elimination of air travel for tourism, change in diet to enforced vegan, and so on) to achieve zero carbon dioxide emissions. There has been no discussion of the reality of what it would take to achieve zero carbon emissions.
Public support for pointless ‘investment’ in green scams will disappear when electrical prices triple, more jobs are lost to Asia, there is no significant reduction in world CO2 emissions, and there is no change in climate changes.

Jake J

Anthony, I tried the link in two different browsers and got ton the same paywall each time.

try following this link and using the scroll bar, the full paper is visible.
Just tried, two different browsers, pay wall is all I can find. Looks like the site may cache credentials, so if you have a subscription or other access that they already recognize, they may be letting you straight in off of that.

Pamela Gray

Anthony, the one I linked to reads almost exactly like the snippet I see on your link. I can’t see the entire paper at your link. So am not sure what scroll bars you are using. They don’t scroll past the abstract for me.

Evan Jones

It’s worse than we thought (is that even possible??)
When IPCC AR4 came out, Jay Leno commented, on his show, to the effect of: “There is a new United Nations report out that says global warming is even worse than they previously predicted. It must be pretty bad. They previously predicted it would destroy the planet.”

Steven Burnett

The Paper is paywalled for me so i can’t check Dr. Tol’s math. However I did read the original Cook paper and came to the same conclusion.
First: the methodology is subjective. Subjectivity is useless
Second: Only one of his 7 categories placed a quantifiable definition of anthropogenic contribution at 50% or greater. This makes the other agreements subjective, and the paper worthless
Third: He compares combinations of different levels of agreement against each other.As most categories are subjective, Comparing numerical and linguistic affirmations is incorrect. thus the paper is useless.
Fourth: There were no significant controls in place for duplicates, rebuttals or pieces unrelated to climate change. Work that has been debunked can still be part of the representative sample. This makes the paper useless..
Fifth: The paper only reviewed the abstracts, that is not the same as reviewing the body of work within the paper. Failure to distinguish between opinion and substantiated evidence maes this paper useless.
Sixth: The source of his independent raters was also a potential source of bias, This makes the results subjective and the paper useless.
Seventh: The raters were not independent, This makes the methodology incorrect and the paper useless.
Eighth: The issue in the climate debates has nothing to do with whether there is or is not an anthropogenic contribution, it is solely about how much,. Failure to restrict the categories to those that have a stated quantifiable human contribution greater than or equal to 50% or more of observed warming makes this paper useless.
Ninth: The policy debate centers around the differences in sensitivity between the models (High) and observations (low). Failure to distinguish papers discussing these variables from those researchers personal beliefs makes the paper useless.
Tenth: Failure to narrowly define consensus makes this paper subjective and therefore useless.
Eleventh: Failure to control for publication rates between researchers, allows more active publishers to skew the data set. This is a source of bias and renders the paper useless.
Twelfth: Science is not a democracy, The failure of a hypothesis to a single repeatable experiment or falsifying evidence is all that matters. Quantifying the consensus is therefore worthless.
thirteenth : Failure to recognize the meaningless nature of consensus in science is a failure of the researcher. Any work produced to that end is there fore useless.
fourteenth Groupthink and the inherent problems is well documented. The idea of a consensus reinforces groupthink. The paper is therefor harmful.
Im sure many of those examples seem repetitive but the truth is the analysis committed multiple failures from concept, methodology, data collection, data analysis, conclusion and impact that each iteration of a bad Idea deserves its own mention. Its like keeping a baby in a closet to see if it develops language. Its wrong on so many levels that each nuance deserves its own point.

Steven Burnett….I love you. Thank you for the perfect list of why I hate (and mock) that paper so much.

I had a nice post ready but then looked up and saw Steven Burnett’s so will merely say – Ditto. (although truthfully, his is far more comprehensive than mine was).

It does seem “unusual” – and noteworthy!!! – that a simple paper (by Toll) that criticizes the basic methodology of the supposed 97% claim so fundamental to the CAGW religion is being so suddenly and rigorously attacked here.
Thus, four papers that SUPPORTED and CREATED the 97% fundamentalism from assumptions and from flawed evidence that WAS ITSELF flawed and distorted were immediately accepted, publicized and praised and funded and reproduced around the world. Ten thousand papers and speeches and papers and publicity releases by the government-paid universities and bureaucracies and laboratories that BENEFIT from the 97% fundamentalism creed are accepted as “truth” and used to support that Creed many tens of thousands times more in millions of classrooms.
ONE paper that criticizes the methodology of the 97% fundamentalism myth is IMMEDIATELY criticized and intimately analyzed in point-by-point detail by anonymous writers in a private web blog sponsored by a single individual. But the 97%?
Well, today’s US president would never use a lie to support his agenda, would he?

Michael Jankowski

I wouldn’t put too much weight in Tol’s comments in the conclusions. You basically can’t get a critical climate science paper published without some disclaimers about how you don’t deny the existence of substantial anthropogenic climate change yadda yadda yadda.