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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


Bärbel Winkler lives and works in Germany. She has always had a lot of interest in environmental issues and has been active as a volunteer at the local zoo and a conservation group for many years. Over time and while learning more and more about it, Bärbel became increasingly aware and concerned about climate change and what it will mean for generations to come. As a means to turn her concerns regarding climate change into something productive, Bärbel joined the Skeptical Science team in 2010 and started translating selected content into German. Since 2013 she has been coordinating the translation efforts for all languages and also contributes a blog-post every once in a while

Follow Bärbel on Twitter: @BaerbelW


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., 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+

Jacobs, P. H., Jokimäki, A., Rice, K., Green, S. A., & Winkler, B. (2016). Polluted Discourse: Communication and Myths in a Climate of Denial. In Communicating Climate-Change and Natural Hazard Risk and Cultivating Resilience (pp. 37-54). Springer International Publishing. Link to abstract


Recent blog posts

Paced version of Denial101x starting on March 21!

Posted on 16 March 2017 by BaerbelW &

The next iteration of our free online course, Making Sense of Climate Science Denial, starts on March 21 and will run for 8 weeks as a paced course.

The MOOC (Massive Open Online Course) is a collaboration between Skeptical Science and The University of Queensland and takes an 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. With all the misinformation and outright lies coming out of Washington regarding climate science - not to mention many other topics - our MOOC will give you the knowledge to spot and the tools to effectively counter them.

The course first launched in April 2015. Since then, over 30,000 students from over 160 countries have enrolled in the course. Last year, we were honoured to be named one of the finalists for the first-ever edX Prize for Exceptional Contributions in Online Teaching and Learning (the prize went to TU Delft's Arno Smets). 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:

You can sign up for free via the edX website.

Hope to see you there!



To tweet or not to tweet at Donald Trump? That was the question!

Posted on 8 March 2017 by BaerbelW & John Mason

Knowing Twitter to be the prefered means of communication for the current POTUS and that he “may” have a thing or two to learn about climate science, John Mason recently set out to explain the carbon cycle in a series of 49 tweets in a language we hoped Donald Trump would be able to grasp.

As John explained: “I often wonder if a lot of climate change communication follows formats that may be unattractive to some people. Lengthy posts complete with explanatory graphics are appreciated by many, but others simply may not have the time to work through them for all sorts of reasons. Yet, this should not exclude them from accessing information. So regardless of whether Trump read the tweets or not, I wanted to proceed with this as an experiment in making climate communication available to a wider demographic. The simpler the framing of information, the more quickly it may be scanned and absorbed. I picked a fairly complex aspect of planetary science - Earth’s Carbon Cycle - and set out to simplify it whilst keeping it consistent with what the science says.

So, on February 28, the tweets started to go out on Twitter in a little tweet storm:


A good two hours later the final tweets were sent:




Why claiming that climate scientists are in it for the money is absurd

Posted on 14 February 2017 by BaerbelW &

If you are reading the comments on basically any climate change related article, it won't take long to get to one (or more!) commenters boldly claiming that "climate scientists are only in it for the money". This will often be accompanied by outrageously high $ amounts to really get anybody's hackles up but without any real evidence for their statement.

This article is intended to be a repository listing resources you can use to counter this unsubstantiated claim whenever it crops up somewhere. Some are blog posts, some are videos while others come from social media postings.


One of the best explanations of why the claim is just absurd comes from Richard Alley in this interview snippet:

Many of the scientists interviewed for Denial101x also explain why they do what they do and it doesn't have anything to do with money (big surprise!). All those expert interviews are available in the Wakelet-collection Denial101x Expert Interviews

Blog Posts

John Timmer in ArsTechnica (May 2012) - Accusations that climate science is money-driven reveal ignorance of how science is done



2016 in Review: a recap of what happened at Skeptical Science

Posted on 31 December 2016 by BaerbelW &

Considering what all our team of volunteers managed to get done in 2015 we didn't really go into 2016 with the expectation to "beat" it as far as productivity goes. But, as it turned out, this review article for 2016 is about the same length as last year's so we at least haven't taken a sabbatical! As this post is quite long, you can jump to the different sections via the following links:

Scholarly Publications and books

Other publications and activities

Our MOOC Denial101x

Conferences and presentations

Social Media and some homepage stats


Scholarly Publications and books

thesisOn August 3 SkS founder John Cook received notification that his PhD thesis had been accepted without revision, so he's now Dr. John Cook (but I have a hunch that he still prefers to be called John, at least by his friends and colleagues!). You can download his thesis, aptly titled "Closing the “consensus gap” by communicating the scientific consensus on climate change and countering misinformation” from SkS. It consists of 9 papers published in peer reviewed journals and other publications, the different chapters woven together into a single document by introductory comments. It makes for quite an interesting read! Congratulations to John for this accomplishment!

John co-authored the paper "The ‘Alice in Wonderland’ mechanics of the rejection of (climate) science: simulating coherence by conspiracism" with Stephan Lewandowsky and Elisabeth Loyd. The three authors look at both rhetorical and scientific arguments put out by deniers and list examples of where these various arguments contradict each other as outlined in Graham Readfearn's explainer.

In October, John's in-depth article "Countering Climate Science Denial and Communicating Scientific Consensus" was published online in the Climate Science Oxford Research Enyclopedias from where it can also be downloaded as a PDF document.

Mark Richardson, Kevin Cowtan and Martin Stolpe from the SkS-team  published "Reconciled climate response estimates from climate models and the energy budget of Earth" in Nature Climate Change with Ed Hawkins as another co-author. You can read more about this paper on Kevin's University of York webpage, where he published a background article.

Robert Way published "Underestimated warming of northern Canada in the Berkeley Earth temperature product" in the International Journal of Climatology with co-authors Frank Oliva and Andre Viau from the University of Ottawa.

ExaminingFactsTogether with Daniel Bedford, John published the textbook "Climate Change: Examining the Facts". From the description:

"Climate change is one of the most controversial and misunderstood issues of the 21st century. This book provides a clear understanding of the issue by presenting scientific facts to refute falsehoods and misinformation―and to confirm the validity of other assertions.

Is public understanding of global warming suffering from politically biased news coverage? Is it true that the global scientific community has not reached a consensus on whether humans are causing climate change? This important book addresses these questions and many more about global warming, identifying common claims about climate change and using quantifiable, evidence-based information to examine their veracity." 

2016 saw continued interest in our consensus study (Cook et al. 2013) with the paper surpassing half a million downloads on ERL's website in early summer. As of this writing, the paper still gets downloaded about 2,000 times per week and currently stands at 570,000+ downloads from ERL, making it the most viewed paper in all of the journals published by the Institute of Physics (IOP). It also gets "talked about" on the net a lot as indicated by Altimetric.

In December, Cook et al. (2013) was included as one of the influential papers in ERL's special collection to celebrate its 10th anniversary publishing peer-reviewed scientific papers. ERL celebrated its anniversary with a reception at this year's AGU:


As a reaction to continued attacks on our paper - and especially a published comment by Richard Tol - we collaborated with the authors of 6 other consensus studies and published "Consensus on consensus: a synthesis of consensus estimates on human-caused global warming" in April (Cook et al. 2016). Both of our consensus papers have been consistently listed among the top 3 of ERL's most viewed papers since then and "Consensus on consensus" just passed 100,000 downloads sometime during the last week of 2016.


Several more publications are currently in the works and we’ll let you know about them once they’ve been published.



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.



Getting involved with Climate Science via crowdfunding and crowdsourcing

Posted on 7 December 2016 by BaerbelW &

At a guess, many of you reading this post are already making good personal choices to help mitigate climate change. Some of you would perhaps like to do more. So, here are some suggestions where you can get actively involved either via crowdfunding, where you make a monetary donation or via crowdsourcing, where you donate your or your computer's time to sift through different sets of data.

This post is divided into three sections:

Ongoing crowdfunding - sites and groups listed here are continously looking for donations

Shortterm crowdfunding - these are projects with a target amount and a set deadline

Crowdsourcing - projects looking for your (or your computer's) time

Ongoing crowdfunding

Climate Science Legal Defense Fund (CSLDF)

Logo-CSLDF The Climate Science Legal Defense Fund was established to make sure that legal actions are not viewed as an attack against one scientist or institution, but as attacks against the scientific endeavor as a whole. As well. the CSLDF protects individual scientists facing unfair legal attacks by organized groups. Given the current climate - pun most definitely intended - in the U.S. the CSLDF's work is unfortunately becoming ever more important. Link to donation page

Dark Snow Project

Jason Box's and Peter Sinclair's The Dark Snow Project gathers ‘hard numbers’ from the Arctic to quantify the distant snow/ice melting impact of industrial and wildfire black carbon soot; mineral dust; and microbes, each melt factor having some human driven enhancement. Link to donation page LogoDarkSnow

The Australian Climate Council

LogoClimateCouncil After thousands of Australians chipped in to Australia's biggest crowd-funding campaign, the abolished Climate Commission has relaunched as the new, independent Climate Council. We exist to provide independent, authoritative climate change information to the Australian public. Why? Because our response to climate change should be based on the best science available. Link to donation page

Citizens’ Climate Education (CCE)

Your donation to Citizens’ Climate Education will train ordinary citizens to promote fair, effective, and non-partisan climate change solutions. Citizens’ Climate Education’s volunteers understand that we owe it to tomorrow’s generations to face our climate challenges today. These informed, respectful citizens work to build a clean and prosperous future, leading elected officials towards solutions that reduce carbon pollution, create jobs, and strengthen the American economy. Link to donation page Logo-CCE

Real Skeptic Blog

Logo-RS The goal of Real Skeptic is to look at claims about science and investigate what the scientific literature has to say about it. Since the official start of Real Sceptic a wide array of articles about skepticism were written for this website. There’s a heavy emphasis on the accuracy of the articles published and the usage of high quality sources. Link to Patreon page

Inside Climate News

InsideClimate News is an essential, global voice that exposes the truth about the climate crisis. We connect the dots to those responsible, so that you can hold them accountable. As we enter our 10th year, we’re launching The InsideClimate Circle to ensure that our award-winning nonprofit news organization remains fiercely independent and courageously persistent. Link to membership page ICN-Log




Dear Mr President-elect: a message from across the Pond

Posted on 29 November 2016 by John Mason & BaerbelW

Dear Mr President-elect,

On 6 Nov 2012, at 11:15 am, you tweeted:

“The concept of global warming was created by and for the Chinese in order to make U.S. manufacturing non-competitive.”

We'd like to take you on a quick tour back through the ages, because the early understanding of Earth's climate - and the role that carbon has to play in it - came from the West, not the East. Let's run through it quickly.

In 1800, British astronomer William Herschel first measured the heat that occurs in the warm – now known as infra-red (IR) – part of the spectrum. In 1824, French engineer Jean Baptiste Joseph Fourier calculated that Earth should be colder than it is, at its orbital distance from the Sun. Today, it is common knowledge that outgoing IR radiation is emitted by the Earth's surface in response to heating by the Sun. But Fourier was the first to figure out that the IR was being slowed down during its journey back out to space. The air, he said, must act as a form of insulating blanket, keeping the planet warm. Smart guy.

This was just two years before Samuel Morey patented the first internal combustion engine.

In 1861, Anglo-Irish physicist John Tyndall observed that some atmospheric gases were transparent to IR radiation. But he found that others, like water vapor and carbon dioxide, were powerful IR absorbers. He was the first to propose that changes in the amount of carbon dioxide in the atmosphere could influence the Earth's climate. In 1896, Swedish scientist Svante Arrhenius took it further. He made the first detailed calculations to see what a doubling of carbon dioxide levels might do to temperatures. His answer was a 5-6°C increase in the average global temperature. His ‘hot-house theory’ was set out for the first time in 1908 in his popular book ‘Worlds in the Making’.

In 1909, American astronomer Andrew Douglass developed the techniques of studying tree-rings and was the first to find the connection between tree ring widths and climate. In 1931, American physicist E.O Hulburt ran calculations to determine the effect of doubling carbon dioxide with the added burden of water vapor. His figure? 4°C of warming. In 1938, English engineer Guy Callendar discovered evidence of a warming temperature trend in the early twentieth century. He also found that CO2 levels were increasing and he warned that over the coming centuries there could be a climate shift to a permanently warmer state.



Join the self-paced version of Denial101x - Making sense of climate science denial!

Posted on 20 October 2016 by BaerbelW &

The next run of our free online course, Making Sense of Climate Science Denial, started on Oct. 18 and will be open until March 7, 2017 as a self-paced course. This means that there are no deadlines apart from the final day of the MOOC and that you can work through all of the material as your time allows. If you participated in one of the earlier iterations but missed some deadlines, this is the opportunity to see it through.

The MOOC (Massive Open Online Course) is a collaboration between Skeptical Science and The University of Queensland, that takes an 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.



Handy resources when facing a firehose of falsehoods

Posted on 3 May 2016 by BaerbelW & jg

Chances are high that you will have come across somebody somewhere on the internet who still doesn't accept the overwhelming scientific consensus on human-caused global warming. That somebody may well have used a veritable firehose of falsehoods - usually referred to as a gish-gallop - where a big list of myths is fired off in quick succession. Creating such a gish-gallop is quick & easy and the urge to try and debunk all the misinformation it contains is often quite strong, but it's also a very time-consuming task to undertake. One time-saving option to tackle it, is to just concentrate on the most egregious instances of misinformation as examples of how the writer tries to mislead his readers and to ignore the rest. But, this has the disadvantage that others might accuse you of cherry-picking what you chose to debunk.

So, what other options do you have to fairly quickly dispense with such a firehose of falsehoods?

Option #1 - The Fact-Myth-Fallacy overview

Our MOOC Denial101x debunked around 50 of the most often heard myths related to climate science using the recipe to start out with the fact, followed by a short mention of the myth (with a warning!) and finishing off with explaining the fallacy employed. A condensed version of these debunkings is available as a four-page-PDF which you can download from here:

Fact-Myth-FallacyThe fallacies are based on the five techniques used by science deniers to distort facts: fake experts, logical fallacies, impossible expectations, cherry picking evidence, and conspiracy theories. The acronym FLICC is an easy way to remember these techniques.

FLICC: Fake experts, Logical fallacies, Impossible expectations, Cherry picking, Conspiracy theories. John Cook



The Uncertainty Handbook: Download and Translations

Posted on 23 February 2016 by BaerbelW &

UHB-EN-ThumbHave you ever struggled with the communication of climate change uncertainties? Are you frustrated by climate sceptics using uncertainty - inherent in any area of complex science - as a justification for delaying policy responses? Then the new ‘Uncertainty Handbook’ - a collaboration between the University of Bristol and Climate Outreach (former COIN) - is for you.

The Handbook distills the most important research findings and expert advice on communicating uncertainty into a few pages of practical, easy-to-apply techniques, providing scientists, policymakers and campaigners with the tools they need to communicate more effectively around climate change. Download the report here, and check out our 12 principles for more effectively communicating climate change uncertainty here.


The Authors:

The Uncertainty Handbook was authored by Dr. Adam Corner (Climate Outreach), Professor Stephan Lewandowsky (University of Bristol), Dr Mary Phillips (University of Bristol) and Olga Roberts (Climate Outreach). All are experts in their fields and have expertise relating to the role of uncertainty in climate change or how best to communicate it.



Get It Here or via iBooks.

The Consensus Project Website



(free to republish)



The Scientific Guide to
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