James Powell is wrong about the 99.99% AGW consensus

James Powell is wrong about the 99.99% AGW consensus

In a recent article in Skeptical Inquirer, geologist and writer James Lawrence Powell, claims that there is a 99.99% scientific consensus on Anthropogenic Global Warming (AGW). You might think that after all of the harsh criticism that the 2013 Cook et al. paper (C13) has received from climate contrarians that we would be pleased to embrace the results of a critique that claims we were far too conservative in assessing the consensus. While it certainly does make a nice change from the usual rants and overblown methodological nit-picks from the contrarians, Powell is wrong to claim such a very high degree of agreement.

He makes many of the same errors that contrarian critics make: ignoring the papers self-rated by the original authors; and making unwarranted assumptions about what the “no-position” abstracts and papers mean.

Powell’s methodology was to search the Web of Science to review abstracts from 2013 and 2014. He added the search term “climate change” to the terms “global climate change” and “global warming” that were used by C13.  He examined 24,210 papers co-authored by 69,406 scientists and found only five papers written by four authors that explicitly reject AGW. Assuming the rest of the abstracts endorsed AGW, this gives consensus figures of 99.98% (by abstract) and 99.99% (by author).

His definition of explicit rejection would align roughly with the seventh level of endorsement used in C13: “Explicitly states that humans are causing less than half of global warming” . In the abstracts from 1991-2011, C13 found 9 out of 11,914 that fit level 7, which using Powell’s consensus calculation assumptions, would yield 99.92%. So, there is probably not much difference between the two approaches when it comes to identifying an outright rejection paper. It’s what you assume the other abstracts say—or do not say—that is the problem.

C13 also counted as “reject AGW” abstracts that: “Implies humans have had a minimal impact on global warming without saying so explicitly, e.g., proposing a natural mechanism is the main cause of global warming”. These are more numerous than the explicit rejections and include papers by scientists who consider that natural causes are more important than human causes in recent warming, but who do not outright reject some small human contribution.

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Competing Climate Consensus Pacmen. Cook on the left, Powell on the right.

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Temperature tantrums on the campaign trail

Temperature tantrums on the campaign trail

Originally published at Corporate Knights on March 17, 2016.

Sorry Ted Cruz. There’s no conspiracy among scientists to exaggerate global warming by fudging the numbers.

Last year was the warmest year recorded since the measurement of global surface temperatures began in the nineteenth century. The second-warmest year ever was 2014. Moreover, because of the persisting effects of the equatorial Pacific Ocean phenomenon known as El Niño, many experts are predicting that 2016 could set a new annual record. January and February have already set new monthly records, with February half a degree Celsius warmer than any February in history.

This news is deeply unsettling for those who care about the future of the planet. But it is even more upsetting for people opposed to climate mitigation, since it refutes their favourite talking point – that global warming has stalled in recent years.

U.S. Congressman Lamar Smith claims there has been a conspiracy among scientists to fudge the surface temperature records upwards and has demanded, by subpoena, to have scientists’ emails released.

Senator and presidential candidate Ted Cruz recently organized a Senate hearing on the temperature record in which he called upon carefully selected witnesses to testify that calculations of temperature made by satellite observations of the upper atmosphere are superior to measurements made by thermometers at the Earth’s surface.

It’s easy to cherry-pick data in order to bamboozle people. The process of making consistent temperature records from surface measurements and satellite observations is complicated and is easy to misrepresent.

But the fact remains that there are no conspiracies afoot. Here’s why. Continue reading

The Exxon scandal: an industry insider’s view

I have no additional beans to spill about Exxon’s internal discussions on climate change, so if that is what you were looking for, I offer my apologies and advise you to read no further.

Nor will I spend much time rehashing the recent reports from Inside Climate News, the LA Times, the New York Times or the Guardian that recount what Exxon knew about climate change and what they did to promote doubt and delay climate policy in recent years . What I will offer is my perspective as an ex-oil industry insider on Exxon’s corporate culture and why their downplaying of their own in-house research is perhaps even worse than it appears. I’ll also look at how differently Exxon approached climate change compared to BP and Shell.

I have never worked for Exxon but, in my 30-plus years of oil industry experience, I have had a fair bit of exposure to Exxon’s culture through being involved with project partnerships with them, interactions with Exxon employees at technical conferences, and working with colleagues who had spent their formative years at Exxon. Most of my career was spent working for lesser-known, mid-size companies (Husky Oil, OMV, Encana) rather than the notorious Big Oil Companies. From the perspective of the smaller companies, the giant multinationals are seen as lumbering beasts, slow to act, slow to innovate, secretive and over-confident. Exxon was the biggest of the lumbering beasts, easy to run rings around in mature basins. As an example, consider how the big companies were bystanders and taken by surprise in the North American fracking revolution. Continue reading

Unsure about how to talk about uncertainty? Read this

2015-07-05_15-39-46Adam Corner, Stephan Lewandowsky, Mary Phillips, and Olga Roberts have today published The Uncertainty Handbook, which is a twenty-page practical guide for climate communicators. It is excellent, clearly written and I recommend that everyone read it all. Adam Corner has a blogpost outlining the Handbook at Shaping Tomorrow’s World.

As the authors say, everyone is already familiar with making decisions under uncertainty. To make plans means accepting that they may not unfold as expected. The natural world is chaotic, with many known-unknowns and unknown-unknowns. The human world is even more unpredictable. We all develop rules-of-thumb to deal with everyday uncertainty: whether to take an umbrella, when to take a vacation, whose advice to trust. But we humans do not always have good instincts when it comes to grasping the uncertainty of novel and unfamiliar situations. As Daniel Kahneman showed in his masterpiece Thinking, Fast and Slow we are often not very smart when confronting probability or logic problems in our lives, especially when they are expressed numerically.  The Economist reviewer wrote:

In one experiment described by Mr Kahneman, participants asked to imagine that they have been given £50 behave differently depending on whether they are then told they can “keep” £20 or must “lose” £30—though the outcomes are identical. He also shows that it is more threatening to say that a disease kills “1,286 in every 10,000 people”, than to say it kills “24.14% of the population”, even though the second mention is twice as deadly. Vivid language often overrides basic arithmetic.

Framing is everything.

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You can now run a MOOC at your own pace, from July 1

The Denial 101x MOOC (Massive Open Online Course) was a great success, with thousands of participants and many satisfied students. I admit that I was quite touched by the mostly positive student reactions and I am thankful to John Cook for inviting me to contribute to this course in a small way. This video compilation of students’ feedback shows how people from diverse backgrounds all got something from the course.

From July 1, 2015 onwards, the course is available for anyone to follow at their own pace. It’s completely free of charge, naturally!

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Why the 97 per cent consensus on climate change still gets challenged

Here are some excerpts from an article I wrote  for the magazine Corporate Knights, that was published on May 14, 2015. Some references and links have been added at the end. This is cross-posted with Skeptical Science.

In 2004, science historian Naomi Oreskes published a short paper in the journal Science concluding there was an overwhelming consensus in the scientific literature that global warming was caused by humans.

After the paper’s release, there was some unexpectedly hostile reaction. This prompted Oreskes and her colleague Erik Conway to go even deeper with their research, leading to the publication of the book Merchants of Doubt. It documents how a small group of scientists with links to industry were able to sow doubt about the scientific consensus and delay effective policy on DDT, tobacco, acid rain and, now, global warming.

Fast forward to two years ago: a team of volunteer researchers (myself included) associated with the website Skeptical Science decide to update and extend Oreskes’ research. Led by University of Queensland researcher John Cook, we analyzed the abstracts of about 12,000 scientific papers extracted from a large database of articles, using the search terms “global warming” and “global climate change.” The articles had been published over a 21-year period, from 1991 to 2011.

As an independent check on our results, we also sent emails to the more than 8,500 scientist authors of these articles. (These were the scientists whose e-mail addresses we were able to track down). We asked them to rate their own papers for endorsement or rejection of man-made global warming.

Both approaches yielded a very similar result: 97 per cent of the scientific literature that expresses an opinion on climate change endorses the expert consensus view that it is man-made. The results were published in May 2013 in the journal Environmental Research Letters.

We were astonished by the positive reception. Mention of the paper was tweeted by U.S. President Barack Obama, Al Gore and Elon Musk, among others. Obama later referenced it in a speech at the University of Queensland, while U.S. Secretary of State John Kerry has referred to the 97 per cent consensus in recent speeches. John Oliver based an episode of his HBO comedy show Last Week Tonight around it, a clip viewed online more than five million times.


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Skeptical Science is running a MOOC

The volunteers at Skeptical Science, along with staff at the University of Queensland, have been busy over the past several months putting together a Massive Open Online Course (MOOC) on climate change. The course, Making Sense of Climate Science Denial, starts on April 28th and is free to anyone who wants to participate. It will last for seven weeks and will require an hour or two of attention every week.

The University of Queensland has a press release.

Thousands of people have already signed up, but we are hoping for many more. Learning will not just come from watching the many short video lectures we have prepared, but from discussions with fellow students. So, no matter what your level of knowledge, or  your point of view on man-made climate change might be, please join us. I’m looking forward to learning from this course, too.

All anyone needs is an Internet connection, a desire to learn and share your knowledge, and an ability to understand English spoken in American, British, Canadian and Australian accents.

Watch the trailer:

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Dreadful GSA blogpost by Canadian geologists

Geologists, especially those, like me, of a certain age, often have problems with climate science and the idea that humans may be triggering a massive and abrupt change in the climate. Global change, we were taught, occurred slowly and by commonplace mechanisms: sediment carried by water, deposited a grain at a time: erosion effected by water and wind, the hardest rocks slowly ground down crystal by crystal. The great features of the Earth—the canyons, mountains and basins—were built this way and owe their grandeur to Deep Time, geology’s greatest intellectual gift to human culture. In the face of the history of the natural world, geologists feel a certain humility at the insignificance of humans and our tiny lifespans. But we also feel some pride in the role of our subject in piecing together this history from fossils and outcrops of rock. It’s an amazing detective story: diligent scientists patiently working away and uncovering the Earth’s great secrets.

 

Then climate science comes along and grabs all the headlines. Suddenly, we hear, change is coming fast and the outcome could be ugly. The familiar music of natural geological change is about to be disrupted by a noisy interruption in the form of human intervention. To add insult to injury, many of the people delivering this disruptive message do not seem—at least to some geologists—to be sufficiently deferential to the extensive knowledge about the slow and cyclic changes in the geological past.

This is quite false, as I found out for myself. My initial reaction many years ago to hearing about climate change was one of disbelief, mixed with a strong suspicion that the climate forecasters had neglected to take the lessons of Earth history into account. I soon found out that I was completely wrong about this. I confess also, as I read the scientific literature, that I learned more about modern geology than I had in many years working as an industrial geoscientist. Unknown to me, immersed in my own areas of specialty, geology had moved on, especially in palaeoclimatology.

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Don’t Even Think About It: Why our Brains are Wired to Ignore Climate Change—a book review

George Marshall has written a book that is essential reading for everyone interested in communicating the science of climate change and its urgent policy implications. Don’t Even Think About It: Why Our Brains Are Wired to Ignore Climate Change comprises 43 short and well-written chapters that explain why  strenuous efforts to spread the word and spur action on climate change have failed.

There is no question that the problem is far from licked: the Keeling Curve continues its upward rise; American conservatives remain stuck in an intellectual dead end on climate; other countries pay lip service to the threat while making only token gestures to solve it; every year there is a big international get-together at COP meetings where thousands of delegates gather to push the policy boulder up Sisyphus’ hill, only to watch it roll down again. Opinion polls, it is true, show that there is broad public acceptance of the scientific basis of climate change, but the understanding of the problem is shallow. People say they care about climate change, but when it comes time to vote, other issues loom larger.

Marshall has worked for 25 years as a campaigner in environmental movements, including Greenpeace US and the Rainforest Foundation. He is a co-founder of the Climate Outreach Information Network, a UK based charity committed to ensuring that climate change and its impacts are understood and acted upon. Continue reading

Consensus Matters

The publication of the paper that I co-authored, Quantifying the consensus on anthropogenic global warming in the scientific literature,  in May 2013 caused quite a splash. The paper received a lot of positive coverage, including Tweets from Barack ObamaAl Gore and Elon Musk.  (They didn’t always get the details quite right: our survey was of the literature, not of scientists’ opinions and we had nothing to say about how dangerous climate change would be.) The paper has been downloaded, as of June 2nd 2014, 183,335 times, which is a record for any Institute of Physics paper. The editorial board of the journal, Environmental Research Letters, awarded the paper the “Best article of 2013” prize.  The research for the paper was done by a team of unpaid non-specialist volunteers of students and industrial and academic scientists, along with other enthusiasts and the funding for its publication was raised by donations from Skeptical Science readers. No taxpayers were harmed during the making of this article.

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Not everybody was pleased to see our work in print. In particular, many people who are unconvinced of the urgency to act on mitigating climate change have been claiming that our study is flawed and biased. Even somebody like economist Richard Tol—who accepts that global warming is real and caused by humans and who acknowledges that there is an overwhelming scientific consensus—has made extraordinary efforts over the past year to get a critique published. He finally succeeded, with the paper Quantifying the consensus on anthropogenic global warming in the literature: A re-analysis published in the journal Energy Policy,. The journal editors somehow came to believe that this article fell within its scope of  being “an international peer-reviewed journal addressing the policy implications of energy supply and use from their economic, social, planning and environmental aspects“.

Energy Policy was good enough to give us a chance to respond, which we did with this short paper, which has now (June 21, 2014) been  published. We were only allowed 1000 words, however, so we wrote a much longer article, published on the Skeptical Science website, detailing the 24 errors that Professor  Tol made. Continue reading