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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Climate Hustle

John Cook

John is an Research Assistant Professor at the Center for Climate Change Communication at George Mason University. He holds a PhD in cognitive psychology at the University of Western Australia and a Bachelor of Science at the University of Queensland, achieving First Class Honours with a major in physics. He co-authored the 2011 book Climate Change Denial: Heads in the Sand with Haydn Washington, and the 2013 college textbook Climate Change Science: A Modern Synthesis with Tom Farmer. He also lead-authored the paper Quantifying the Consensus on anthropogenic global warming in the scientific literature, which was tweeted by President Obama and was awarded the best paper published in Environmental Research Letters in 2013.


Cook, J., Lewandowsky, S., & Ecker, U. (in press). Neutralizing Misinformation Through Inoculation: Exposing Misleading Argumentation Techniques Reduces Their Influence. PLOS ONE. doi:10.1371/journal.pone.0175799

Cook, J. (2017). How to Effectively Debunk Myths About Aging and Other MisconceptionsPublic Policy and Aging Report. 27(1), 13-17. doi: 10.1093/ppar/prw034

Cook, J. (2016). Closing the “consensus gap” by communicating the scientific consensus on climate change and countering misinformation. (Doctoral dissertation, University of Western Australia).

Bedford, D., & Cook, J. (2016). Climate Change: Examining the Facts. Santa Barbara, CA: ABC-CLIO.

Cook, J. (2016). Countering Climate Science Denial and Communicating Scientific Consensus. Oxford Encyclopedia of Climate Change Communication. London: Oxford University Press.

Lewandowsky, S., Cook, J., & Lloyd, E. (2016). The ‘Alice in Wonderland’mechanics of the rejection of (climate) science: simulating coherence by conspiracismSynthese, 1-22.

Cook, J., Oreskes, N., Doran, P. T., Anderegg, W. R., Verheggen, B., Maibach, E. W., Carlton, J. S., Lewandowsky, S., Skuce, A. G., Green, S. A., & Nuccitelli, D. (2016). Consensus on consensus: a synthesis of consensus estimates on human-caused global warming. Environmental Research Letters, 11(4), 048002.

Cook, J. & Lewandowsky, S. (2016). Rational Irrationality: Modeling Climate Change Belief Polarization Using Bayesian Networks. Topics in Cognitive Science.

Cook, J., Schuennemann, K., Nuccitelli, D., Jacobs, P., Cowtan, K., Green, S., Way, R., Richardson, M., Cawley, G., Mandia, S., Skuce, A., & Bedford, D. (April 2015). Denial101x: Making Sense of Climate Science Denial. edX

Benestad, R. E., Nuccitelli, D., Lewandowsky, S., Hayhoe, K., Hygen, H. O., van Dorland, R., & Cook, J. (2015). Learning from mistakes in climate researchTheoretical and Applied Climatology, 1-5.

Lewandowsky, S., Cook, J., Oberauer, K., Brophy, S., Lloyd, E. A., & Marriott, M. (2015). Recurrent Fury: Conspiratorial Discourse in the Blogosphere Triggered by Research on the Role of Conspiracist Ideation in Climate DenialJournal of Social and Political Psychology3(1), 142-178.

Cook, J., & Cowtan, K. (2015). Reply to Comment on ‘Quantifying the consensus on anthropogenic global warming in the scientific literature’Environmental Research Letters10(3), 039002.

Cook, J., Ecker, U. & Lewandowsky, S. (2015). Misinformation and how to correct it, Emerging Trends in the Social and Behavioral Sciences. Robert Scott and Stephen Kosslyn (Eds.), Hoboken, NJ: John Wiley and Sons.

Cook, J., Bedford, D. & Mandia, S. (2014). Raising Climate Literacy Through Addressing Misinformation: Case Studies in Agnotology-Based Learning. Journal of Geoscience Education, 62(3), 296-306.

Cook, J., Jacobs, P. (2014). Scientists are from Mars, Laypeople are from Venus: An Evidence-Based Rationale for Communicating the Consensus on Climate. Reports of the National Center for Science Education. 34, 6, 3.1-3.10.

Cook, J. (2014). Research on Climate Consensus Provokes Strong Reactions. The Winnower. Available at

Verheggen, B., Strengers, B., Cook, J., van Dorland, R., Vringer, K., Peters, J., Visser, H. & Meyer, L. (2014). Scientists’ views about attribution of global warmingEnvironmental science & technology48(16), 8963-8971.

Cook, J., Nuccitelli, D., Skuce, A., Way, R., Jacobs, P., Painting, R., Honeycutt, R., Green, S.A. (2014). Reply to Comment on ‘Quantifying the consensus on anthropogenic global warming in the scientific literature: a Reanalysis’. Energy Policy. DOI: 10.1016/j.enpol.2014.06.002

Cook, J., Nuccitelli, D., Skuce, A., Way, R., Jacobs, P., Painting, R., Lewandowsky, S. & Coulter, A. (2014). 24 critical errors in Tol (2014): Reaffirming the 97% consensus on anthropogenic global warming.

Cook, J. (2014). How Has the Carbon Tax Affected the Public ‘Debate’ on Climate Change? Quiggin, J., Adamson, D., & Quiggin, D. (Eds.), In Carbon Pricing: Early Experience and Future Prospects (pp. 49-64). Cheltenham Glos: Edward Elgar Publishing.

Abraham, J. P., Cook, J., Fasullo, J. T., Jacobs, P. H., Mandia, S. A. & Nuccitelli, D. A. (2014). Review of the Consensus and Asymmetric Quality of Research on Human-Induced Climate Change, Cosmopolis, 2014-1, 3-18.

Farmer, G. T. & Cook, J. (2013). Climate Change Science: A Modern Synthesis. Dordrecht, Netherlands: Springer Science+Business Media.

Cook, J., Nuccitelli, D., Green, S. A., Richardson, M., Winkler, B., Painting, R., Way, R., Jacobs, P., & Skuce, A. (2013). Quantifying the consensus on anthropogenic global warming in the scientific literature. Environmental Research Letters, 8(2), 024024+.

Bedford, D., & Cook, J. (2013). Agnotology, Scientific Consensus, and the Teaching and Learning of Climate Change: A Response to Legates, Soon and Briggs. Science & Education, 22(8), 2019-2030.

Nuccitelli, D., Way, R., Painting, R., Church, J., & Cook, J. (2012). Comment on ocean heat content and Earth's radiation imbalance. II. Relation to climate shifts. Physics Letters A, 376(45), 3466-3468.

Lewandowsky, S., Ecker, U. K., Seifert, C. M., Schwarz, N., & Cook, J. (2012). Misinformation and its correction continued influence and successful debiasing. Psychological Science in the Public Interest, 13(3), 106-131.

Washington, H., & Cook, J. (2012). Climate change denial: Heads in the sand. Routledge.

Cook, J., & Lewandowsky, S. (2011). The Debunking Handbook. St. Lucia, Australia: University of Queensland. ISBN 978-0-646-56812-6. [available at].


Recent blog posts

Heartland Institute's misinformation campaign into schools

Posted on 21 April 2017 by John Cook &

Last month, the Heartland Institute sent a climate denial booklet to 25,000 teachers around the US. In Episode 8 of the Evidence Squared podcast, we look at the why and how of this book. What is the chief motivation for the book’s misinformation and what are the techniques they employ to cast doubt on climate science?

Follow Evidence Squared on iTunesFacebookTwitterYouTube and Soundcloud.



New podcast Evidence Squared by John Cook & Peter Jacobs

Posted on 29 March 2017 by John Cook &

Since arriving in the US two months ago, I've been developing a podcast with Peter Jacobs, a PhD student studying paleoclimate at George Mason University. While there are a number of podcasts about climate change, there were no podcasts about the science of science communication, how to talk about climate change. Today, we've launched our podcast, Evidence Squared.

You can check us out on iTunes and listen to our first four episodes (more on those in a moment). Be sure to subscribe and rate us



What do gorilla suits and blowfish fallacies have to do with climate change?

Posted on 10 February 2017 by John Cook &

The ConversationThis article was originally published on The Conversation. Read the original article.

A famous psychology experiment instructed participants to watch a short video, counting the number of times players in white shirts passed the ball. If you haven’t seen it before, I encourage you to give the following short video your full attention and follow the instructions:


At the end, participants discovered the point of the video when asked if they had observed the gorilla walking through the players. Half the participants didn’t notice the gorilla at all. The lesson? When we laser-focus on specific details (like players in white shirts), we can miss the gorilla in the room.

What does this have to do with climate change? I’m a cognitive psychologist interested in better understanding and countering the techniques used to distort the science of climate change. I’ve found that understanding why some people reject climate science offers insight into how they deny science. By better understanding the techniques employed, you can counter misinformation more effectively.

Every movement that has rejected a scientific consensus, whether it be on evolution, climate change or the link between smoking and cancer, exhibits the same five characteristics of science denial (concisely summarized by the acronym FLICC). These are fake experts, logical fallacies, impossible expectations, cherry picking and conspiracy theories. When someone wants to cast doubt on a scientific finding, FLICC is an integral part of the misinformation toolbox.

The five characteristics of science denial. Skeptical Science, CC BY-ND



Skeptical Science at AGU 2016 - a recap

Posted on 26 December 2016 by BaerbelW & John Cook

This year's Fall Meeting of the American Geophysical Union (AGU) has come and gone and quite a lot happened during the week from Dec. 12 to 16. As mentioned in our earlier post, several SkS teammembers were actively involved with giving talks and/or presenting posters while others were there to take it all in as was the case for me with attending AGU for the very first time.

This post is a (long) recap divided into the following sections:

SkS presentations

Denial101x featured in a poster session

Rally to stand up for Science

ERL's 10th anniversary reception

NCSE Friend of the Planet awards

Interviewing Stephan Lewandowsky

Further Reading


Some impressions from AGU 2016 (photos: Baerbel Winkler)

SkS presentations

John Cook presented a talk A Brief History of Consensus (PPT 6.8Mb), outlining the misinformation campaign against consensus, the studies quantifying the level of scientific agreement and how to neutralise misinformation.

Dana Nuccitelli presented a talk on climate model accuracy – comparing past global temperature projections to observations, and effectively debunking associated myths.  The model-data comparisons can be seen in the video below.



Skeptical Science at AGU 2016

Posted on 11 December 2016 by John Cook &

Next week is going to be an exciting and busy period for Skeptical Science. Several of us will be presenting talks and posters at this week's AGU 2016 Fall Meeting.


John Cook and Dana Nuccitelli will each be presenting talks in a Monday morning session on climate literacy (session ED12A in Moscone South, room 307). This session will also feature Naomi Oreskes, Richard Alley, Mark Jacobson, Peter Sinclair, Stephan Lewandowsky and Alan Robock - not to be missed!)

John Cook will be presenting a poster about our Denial101x MOOC  in a poster session on science communication through curricula (ED13A-0923) on Monday afternoon. You can check out the poster below (full PDF 28Mb):

Sarah Green (who happens to cameo in John Cook's poster shown above, sporting a very fashionable jacket!) is also presenting a poster Monday afternoon:



Trump or NASA – who's really politicising climate science?

Posted on 25 November 2016 by John Cook &

This article was originally published on The Conversation. Read the original article.The Conversation

Climate research conducted at NASA had been “heavily politicised”, said Robert Walker, a senior adviser to US President-elect Donald Trump.

This has led him to recommend stripping funding for climate research at NASA.

Walker’s claim comes with a great deal of irony. Over the past few decades, climate science has indeed become heavily politicised. But it is ideological partisans cut from the same cloth as Walker who engineered such a polarised situation.

Believe it or not, climate change used to be a bipartisan issue. In 1988, Republican George H.W. Bush pledged to “fight the greenhouse effect with the White House effect”.

Since those idealistic days when conservatives and liberals marched hand-in-hand towards a safer climate future, the level of public discourse has deteriorated.

Surveys of the US public over the past few decades show Democrats and Republicans growing further apart in their attitudes and beliefs about climate change.

For example, when asked whether most scientists agree on global warming, perceived consensus among Democrats has steadily increased over the last two decades. In contrast, perceived consensus among Republicans has been in stasis at around 50%.

Polarisation of perceived consensus among Republicans and Democrats. Dunlap et al. (2016)



Debunking climate myths with Leonardo DiCaprio's Before The Flood

Posted on 29 October 2016 by John Cook &

On Sunday October 30, 9 PM EST, Leonardo DiCaprio's film Before The Flood will screen free online as well as on National Geographic. The film explores the causes and impacts of climate change, arguing for urgent action and a rapid transition off fossil fuels.

It will be streamed all week on Facebook, Youtube, Hulu, Playstation, and can be viewed on demand on Apple iTunes, Amazon, and GooglePlay. Here's more details on how to see the film and here's the trailer:

I was invited to contribute to, debunking some of the most common myths about climate change. Here are my pages on Leonardo DiCaprio's site:



Researching climate change communication at George Mason University

Posted on 7 September 2016 by John Cook &

Next January, I’ll be relocating to the Center for Climate Change Communication at George Mason University. For a Brisbane boy who has never lived outside of Australia, moving to walking distance from Washington, DC is a big call. Two factors influenced this life-changing decision.

First, since I initially learnt about psychological research into debunking, my approach to climate communication has been guided by social science. When I started my research fellowship at GCI at The University of Queensland, my two-pronged approach was to research how to better communicate science, while putting that research into practice. 

As we communicated the scientific consensus on climate change, I also ran psychological experiments into the efficacy of consensus messaging. While we’ve debunked over 190 climate myths, we’ve also published the Debunking Handbook, a summary of psychological research into misinformation. Our MOOC on climate science denial is informed by a synthesis of cognitive psychology, inoculation theory and educational research.

What attracted me to MASON'S Center for Climate Change Communication (or 4C) was their approach to climate communication: a mix of theoretical research combined with practical outreach. They’re not ivory tower boffins - they directly engage with the public, putting into practice their research into the psychology of climate change.

Second, I was also enticed by the collaborative research environment at 4C - a center of scientists and students conducting academic research into the psychology of climate communication. The potential for future lines of enquiry springing from that community is quite exciting.

So after long, thoughtful conversations with my family plus focused research into how to source Vegemite in the U.S., I made the life-changing decision to relocate to the USA. Over the last five years that I’ve been at The University of Queensland, the Skeptical Science team has achieved impact far beyond our expectations, being highlighted by Senators, Presidents and Prime Ministers. My hope is that working at 4C will take our societal impact to another level.



One Nation's Malcolm Roberts is in denial about the facts of climate change

Posted on 5 August 2016 by John Cook &

This article was originally published on The Conversation. Read the original article.The Conversation

The notion that climate science denial is no longer a part of Australian politics was swept away yesterday by One Nation Senator-Elect Malcolm Roberts.

In his inaugural press conference, Roberts claimed that “[t]here’s not one piece of empirical evidence anywhere, anywhere, showing that humans cause, through CO₂ production, climate change”.

He also promoted conspiracy theories that the CSIRO and Bureau of Meteorology are corrupt accomplices in climate conspiracy driven by the United Nations.

His claims conflict with many independent lines of evidence for human-caused global warming. Coincidentally, the University of Queensland is releasing a free online course this month examining the psychology and techniques of climate science denial. The very first video lecture addresses Roberts’ central claim, summarising the empirical evidence that humans are causing climate change.

Consensus of Evidence (from Denial101x course)

Scientists have observed various human fingerprints in recent climate change, documented in many peer-reviewed scientific papers.

Satellites measure less heat escaping to space at the exact wavelengths at which CO₂ absorbs energy. The upper atmosphere is cooling at the same time that the lower atmosphere is warming – a distinct pattern unique to greenhouse warming. Human activity is also changing the very structure of the atmosphere.

Human fingerprints in climate change Skeptical Science



Online course on climate science denial starts Aug 9

Posted on 2 August 2016 by John Cook &

The next run of our free online course, Making Sense of Climate Science Denial, launches next Tuesday, August 9. The MOOC (Massive Open Online Course) is a collaboration between Skeptical Science and The University of Queensland, that takes a interdisciplinary look at climate science denial. We explain the psychological drivers of denial, debunk many of the most common myths about climate change and explore the scientific research into how to respond to climate misinformation.

The course first launched in April 2015. Since then, over 25,000 students from over 160 countries have enrolled in the course. A few weeks ago, we were honoured to be named one of the finalists for the first-ever edX Prize for Exceptional Contributions in Online Teaching and Learning. We've received some wonderful feedback from students who've taken the course, particularly teachers who are using our course videos in their classes. Here is a video compilation of some feedback from the students:



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