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The Contender
Con (against)
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The claim that "97% of scientists agree 'man made global warming' exists" is a lie.

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Voting Style: Open Point System: 7 Point
Started: 10/26/2015 Category: Science
Updated: 11 months ago Status: Post Voting Period
Viewed: 1,187 times Debate No: 81592
Debate Rounds (3)
Comments (17)
Votes (1)




John Kerry has been quoted as saying, "And let there be no doubt in anybody"s mind that the science is absolutely certain. . . 97 percent of climate scientists have confirmed that climate change is happening and that human activity is responsible. . . . . they agree that, if we continue to go down the same path that we are going down today, the world as we know it will change"and it will change dramatically for the worse."

This is very false.

But leaving aside the catastrophic/"change dramatically for the worse" assertion which is not supported by any scientific agreement.

The most common source of this 97% number is in Cook et al. (2013) which leaves out the 'catastrophic' part. In Cook"s summary of his paper: "Cook et al. (2013) found that over 97 percent endorsed the view that the Earth is warming up and human emissions of greenhouse gases are the main cause." ( main cause meaning over 50%)

97% of what? Of papers they surveyed. Not climate scientists.

However, if we were to say "97 percent of papers by climate scientists endorsed the view that the Earth is warming up and human emissions of greenhouse gases are the main cause" this too would also false.


This is not a debate on if global warming exists or doesn't exist.
This is not a debate on if global warming is harmful to humans.

This is a debate on the 'Man Made' with the 97% claim.
If it is not man made then it's usage is meaningless, and the claim should not be used.
If there is not a 97% consensus, the the claim should not be used.

My argument is that 97% of scientists, or climate scientists, or climate papers DO NOT agree that 'man made global warming' exists, and anyone who claims this is misrepresenting facts, and that the 97% claim should be disregarded a false.

The Con side must prove that: 97% of scientists/climate scientists/climate papers agree that Warming is Man Made(51%).


Let me jump right in.

You claim that the 97% of scientists absolutely do not side with the notion that global warming is man-made. Quite the opposite, the issue of global warming is a fatal by-product from years of pollution and toxic waste dumping that has called for a need for a change in. Illustrating this point, various organizations are able to prove that 97% of scientists agree that global warming is man-made. According to NASA and their "Scientific Consensus" page, "97 percent or more of actively publishing climate scientists agree..." going so far as to provide footnotes and sources, along with the names of other major scientific organizations to back up its claims, such as John Cook, et al., in "Quantifying the consensus on anthropogenic global warming in the scientific literature," and “Expert Credibility in Climate Change,” published in the National Academy of Sciences and W. R. L. Anderegg. Furthermore, other institutions and respectable websites such as Scientific American (How to Determine the Scientific Consensus on Global Warming) to (Santorum's Climate Consensus Claims).
Debate Round No. 1


As I stated before, and as you mentioned the primary source of this claim is cited from "Cook et al. (2013).

It is from "Cook et al. (2013) that we get the claim, and quoting from the Abstract, "Among abstracts expressing a position on AGW, 97.1% endorsed the consensus position that humans are causing global warming. "

The first issue with “Cook et al. (2013) is
“explicit endorsement with quantification” vs “explicit endorsement without quantification”

Within the Abstract section 2. Methodology, of “Cook et al. (2013), we can observe the paper broken down as follows:

(1) Explicit endorsement with quantification.
(2) Explicit endorsement without quantification
(3) Implicit endorsement
(4a) No position
(4b) Uncertain
(5) Implicit rejection
(6) Explicit rejection without quantification
(7) Explicit rejection with quantification

“explicit endorsement with quantification” is representative of a paper that states that: "Explicitly states that humans are the primary cause of recent global warming"—primary cause in usage meaning more than 50 percent.

This is the only category anyone claiming "X number of papers endorse Man Made Climate Change." should reference, because this is the only category where that statement is true.

“explicit endorsement without quantification” are papers in which the author, by Cook’s admission, did not say whether .001 percent or 1 percent or 50 percent or 100 percent of the warming was caused by man. The crux of "explicit endorsement without quantification" is that man has contributed SOME amount.

Then there is "Implicit endorsement", which "Implies humans are causing global warming. E.g., research assumes greenhouse gas emissions cause warming without explicitly stating humans are the cause".

The important distinction here is that neither the “explicit endorsement without quantification” or the "Implicit endorsement" make the claim that Human beings are the primary cause. However the theory of AGW([Anthropogenic, or human-cause, Global Warming) is that human being ARE the PRIMARY cause.

However within his results he breaks down the summery of abstracts with AGW([Anthropogenic, or human-cause, Global Warming) position (%) as follows:

Endorse AGW 97.1%
Reject AGW 1.9%
Uncertain on AGW 1.0%

In formulating his result of "Endorse AGW", Cook lumps together "Implicit endorsement" & “explicit endorsement without quantification” with “explicit endorsement with quantification”. Thus lumping together papers which suggest that human contribute some portion, with those stating that we are the primary cause.

Further examination of Cooks data shows the truth of the matter:

By his count, the number of articles classified into each category was:

Level 1 = 64
Level 2 = 922
Level 3 = 2910
Level 4 = 7970
Level 5 = 54
Level 6 = 15
Level 7 = 9

The 97% figure was the sum of levels 1-3. Assuming the count is correct—that 97% breaks down as:

Level 1: 1.6%
Level 2: 23%
Level 3: 72%

This shows only 1.6 percent explicitly stated that man-made greenhouse gases caused at least 50 percent of global warming.

Only Level 1 corresponds to "the Earth is warming up and human emissions of greenhouse gases are the main cause." (emphasis mine) Hence when John Cook attributed that view to 97% on the basis of his Cook et. al. (2013) he was misrepresenting 1.6% as 97%. Adding up his categories 5-7, the levels of rejecting of AGW, we find that more papers explicitly or implicitly rejected the claim that human action was responsible for half or more of warming than accepted it. According to Cook's own data.

So no, Cook et. al. did not find that "over 97% endorsed the view that the Earth is warming up and human emissions of greenhouse gases are the main cause."


Not only does Cook's own data not prove the case, but much of cook's data is improperly categorized. As Popular Technology investigated,

Quoted from their interviews:

"Dr. Scafetta, your paper 'Phenomenological solar contribution to the 1900–2000 global surface warming' is categorized by Cook et al. (2013) as; "Explicitly endorses and quantifies AGW as 50+%"

Is this an accurate representation of your paper?
Scafetta: "Cook et al. (2013) is based on a strawman argument because it does not correctly define the IPCC AGW theory, which is NOT that human emissions have contributed 50%+ of the global warming since 1900 but that almost 90-100% of the observed global warming was induced by human emission.

What my papers say is that the IPCC view is erroneous because about 40-70% of the global warming observed from 1900 to 2000 was induced by the sun. This implies that the true climate sensitivity to CO2 doubling is likely around 1.5 C or less, and that the 21st century projections must be reduced by at least a factor of 2 or more. Of that the sun contributed (more or less) as much as the anthropogenic forcings.

The "less" claim is based on alternative solar models (e.g. ACRIM instead of PMOD) and also on the observation that part of the observed global warming might be due to urban heat island effect, and not to CO2.

By using the 50% borderline a lot of so-called "skeptical works" including some of mine are included in their 97%."

Any further comment on the Cook et al. (2013) paper?
Scafetta: "Please note that it is very important to clarify that the AGW advocated by the IPCC has always claimed that 90-100% of the warming observed since 1900 is due to anthropogenic emissions. While critics like me have always claimed that the data would approximately indicate a 50-50 natural-anthropogenic contribution at most.

What it is observed right now is utter dishonesty by the IPCC advocates. Instead of apologizing and honestly acknowledging that the AGW theory as advocated by the IPCC is wrong because based on climate models that poorly reconstruct the solar signature and do not reproduce the natural oscillations of the climate (AMO, PDO, NAO etc.) and honestly acknowledging that the truth, as it is emerging, is closer to what claimed by IPCC critics like me since 2005, these people are trying to get the credit.

They are gradually engaging into a metamorphosis process to save face.

Now they are misleadingly claiming that what they have always claimed was that AGW is quantified as 50+% of the total warming, so that once it will be clearer that AGW can only at most be quantified as 50% (without the "+") of the total warming, they will still claim that they were sufficiently correct.

And in this way they will get the credit that they do not merit, and continue in defaming critics like me that actually demonstrated such a fact since 2005/2006.""



Zexcoiler_Kingbolt forfeited this round.
Debate Round No. 2


Con has forfited the round. My argument stands, Vote Pro.

Con has forfited the round. My argument stands, Vote Pro.


Further, I wanted to include some peer-review against cook's paper.

Climate Consensus and 'Misinformation': A Rejoinder to Agnotology, Scientific Consensus, and the Teaching and Learning of Climate Change (PDF) [Archive]
(Science & Education, pp. 1-20, August 2013)
- David R. Legates, Willie Soon, William M. Briggs, Christopher Monckton of Brenchley

Abstract: Agnotology is the study of how ignorance arises via circulation of misinformation calculated to mislead. Legates et al. (Sci Educ 22:2007–2017, 2013) had questioned the applicability of agnotology to politically-charged debates. In their reply, Bedford and Cook (Sci Educ 22:2019–2030, 2013), seeking to apply agnotology to climate science, asserted that fossil-fuel interests had promoted doubt about a climate consensus. Their definition of climate 'misinformation' was contingent upon the post-modernist assumptions that scientific truth is discernible by measuring a consensus among experts, and that a near unanimous consensus exists. However, inspection of a claim by Cook et al. (Environ Res Lett 8:024024, 2013) of 97.1 % consensus, heavily relied upon by Bedford and Cook, shows just 0.3 % endorsement of the standard definition of consensus: that most warming since 1950 is anthropogenic. Agnotology, then, is a two-edged sword since either side in a debate may claim that general ignorance arises from misinformation allegedly circulated by the other. Significant questions about anthropogenic influences on climate remain. Therefore, Legates et al. appropriately asserted that partisan presentations of controversies stifle debate and have no place in education.

Quantifying the consensus on anthropogenic global warming in the literature: A re-analysis(PDF) [Archive]
(Energy Policy, Volume 73, pp. 701-705, October 2014)
- Richard S. J. Tol

Abstract: 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.

Quantifying the consensus on anthropogenic global warming in the literature: Rejoinder(PDF) [Archive]
(Energy Policy, Volume 73, pp. 709, October 2014)
- Richard S. J. Tol

Abstract: In my critique of Cook et al. (2013), I raised a number of issues (Tol, 2014). Cook et al. (2014) respond to a few only. They do not dispute

(1) that their sample is not representative,
(2) that data quality is low,
(3) that their validation test is not passed,
(4) that they mistake a trend in composition for a trend in endorsement,
(5) that the majority of the investigated papers that take a position on (anthropogenic) climate change in fact do not examine any evidence, and
(6) that there are inexplicable patterns in the data.

Comment on 'Quantifying the consensus on anthropogenic global warming in the scientific literature' (PDF) [Archive]
(Environmental Research Letters, Volume 10, Number 3, March 2015)
- Benjamin John Floyd Dean

Abstract: I read the study by Cook et al with great interest [1]. The study used levels of endorsement of global warming as outlined in their table 2; however, I could see no mention as to how these levels were created and how reliable they were in terms of both inter-rater and intra-rater reliability (Cohen's kappa). Best practice on rater reliability indicates that both inter-rater and intra-rater should have been measured and documented in a study such as Dr Cook's [2] and I am surprised that this fact appears to have been neglected. It would be of considerable benefit to readers for some robust rate reliability metrics to be included, if at all possible.


Zexcoiler_Kingbolt forfeited this round.
Debate Round No. 3
17 comments have been posted on this debate. Showing 1 through 10 records.
Posted by Zexcoiler_Kingbolt 12 months ago
Aaaaaand, my side of the debate was submitted the wrong way. I hate these glitches.
Posted by Zexcoiler_Kingbolt 12 months ago
Challenge accepted, LandonWalsh.
Posted by DATXDUDE 12 months ago
ur mom is upheld
Posted by Lexus 12 months ago
Ah, it's 97.001% therefore the resolution is upheld.
Posted by distraff 12 months ago
Another issue is what is meant by endorsing human caused climate change. The study was done in two phases. The first was where the researchers classified the papers, and the second where the the authors themselves said that their papers supposed/did not support/no opinion of human caused climate change.

Both phases came to similar conclusions so we can know the authors were not just misinterpreting papers.

To be endorsing global warming this debate requires that the scientists to say that at least 51% of global warming come from humans. According to the survey the positions are given in words not numbers. Here are supporting positions:

1. Explicitly states that humans are the primary cause of recent global warming.
2. Explicitly states humans are causing global warming or refers to anthropogenic global warming/climate change as a known fact.
3. Implies humans are causing global warming. E.g., research assumes greenhouse gas emissions cause warming without explicitly stating humans are the cause.

This seems equivalent to saying that humans cause at least 51% of global warming.
Posted by distraff 12 months ago
Think about it. If we are talking about 97% of publishing climatologists then it is fair to assume that they have published papers on the subject. So we can survey papers rather than the people. The only problems with this method is that more experienced scientists have published more papers than less experienced ones so their vote counts for more. But experience is a good thing so maybe this bias is great.

Another problem is that a lot of these scientists have not published anything about climate change that has a explicit opinion of global warming. Another problem is that this survey only looks at papers about climate change so scientists who don't publish about it are left out. So this statistic does not perfectly track scientific opinion although the fact that 97% supports global warming is strong evidence that there is a strong consensus all by itself.

You can read the paper yourself. 66% of all abstracts about climate change have no opinion of human-caused Global Warming, 33% endorse it, and .7% oppose it. If you only look at the ones with an opinion, 97% endorse it.
Posted by LandonWalsh 12 months ago
If you are that cocky Zexcoiler_Kingbolt... Take the challenge.
Posted by Zexcoiler_Kingbolt 12 months ago
Are you sure you aren't Ken Ham?
Posted by LandonWalsh 12 months ago
Hey mayahcw,

I have made it as wide as possible to justify the 97% number.

In relation to climate change as a whole the MOST important factors related to the discussion are:
Is it man made(51+%).
Is the effects of CO2 on climate a constant.
Is it catastrophic to human beings.

The climate change debate would not matter to anyone if it was not claimed that:
1. We are in grave danger.
2. We are the cause.

If one can prove 97% of anything or anyone supports any of the above... You win.
1 votes has been placed for this debate.
Vote Placed by Berend 11 months ago
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Total points awarded:10 
Reasons for voting decision: Con FF'ed. I do not give votes for FF most times, but a simple accepting opening statement is not enough to win over a debate. Some form of convincing rhetoric and sources would been needed. Pro wins my vote.