RUTHFULLY YOURS

Last week week, a routine entry in the searchable database at the website of the South Dakota Department of Environment and Natural Resources indicated that the Dakota Access Pipeline saw an 84-gallon crude-oil spill in April. The environmental Left rushed to publicize the incident as an “I told you so” moment, but activists’ gloating reveals either their cynical dishonesty or their ignorance about how modern pipelines work.

The spill occurred in an Energy Transfer Partners facility specifically equipped to catch spills. Moreover, the precautions in place to prevent environmental damage worked exactly as they should, according to the South Dakota Department of Environment and National Resources.

“As spills go, this spill was contained, all product was cleaned up quickly, and there were no impacts to the environment,” Kim Smith, a spokesperson for the South Dakota department, told me. “The containment system and notification system worked as they should.”

Compare that to the hysterical reaction from leftist activists and their media allies.

Writing in the Guardian, opinionist Julian Brave NoiseCat said that the leak “demonstrates the risk of technological and human failure inherent in crude oil pipelines,” adding that “indigenous communities, ranchers, and workers [are] forced to live under the constant threat of petroleum poisoning.”

Jan Hasselman, a lawyer for the Standing Rock Sioux, told the Huffington Post: “They keep telling everybody that it is state of the art, that leaks won’t happen, that nothing can go wrong. It’s always been false. They haven’t even turned the thing on, and it’s shown to be false.”

And a Clean Technica reporter claimed the incident “drives home an essential truth about all the systems mankind has devised to transport oil from place to place,” adding: “They all leak. Somewhere, somehow, the vile stuff gets out and when it does, it causes untold damage to the environment.”

Crying “consensus” to defend absolutist assertions, climate activists are charging well beyond the threshold of what mainstream science can support. When they turn back toward the ledge to shout “denial” at anyone who has not leapt with them, the word no longer means what they think it does.

This was my argument in “Who’s The Denier Now?,” published in National Review last month. John Cook, lead author of the “97 percent consensus” studies, has responded to that piece by overstating a consensus in defense of an absolutist assertion and then accusing me of “denial.” He also objects to my citation of his work, which I will address first.

I cited Cook only to refute the claim by Senator Bernie Sanders that “97 percent of the scientists who wrote articles in peer-reviewed journals believe that human activity is the fundamental reason we are seeing climate change.” Specifically, I quoted from three studies that Cook surveyed in Environmental Research Letters, showing consensus levels of 78 percent (climate scientists), 82 percent (earth scientists), and 85 percent (scientists) for Sanders-like statements that attribute to humans a primary role in recent warming.

Cook does not question my accuracy, but instead argues that the consensus among climate scientists should be the relevant measure. Thus, for the 82 percent study, he notes that among the subsample of climate scientists the figure rises to 97 percent. For the 85 percent study, among the subsample of climate scientists the figure rises to 90 percent.

None of this changes the picture. Senator Sanders didn’t say climate scientists, he said peer-reviewed scientists. Even using Cook’s preferred subsamples, the range from 78 to 90 to 97 percent does not support an assertion of a 97 percent consensus.

Cook also misses the larger point, which is that Sanders (among others) has a habit of overstating scientific consensus. Besides the example above, I quote Sanders claiming that 97 percent of scientists conclude that climate change “is already causing devastating problems” and claiming that “the vast majority of scientists” say “there is a real question as to the quality of the planet that we are going to be leaving our children and our grandchildren.” I also quote former President Obama tweeting that 97 percent of scientists agree that climate change is “dangerous.” The documented consensus extends to none of these claims.

If Cook anywhere criticized those obvious mischaracterizations of his work as strongly as he now takes issue with my precise citation, I apologize for having missed it. He did comment approvingly on the inaccurate Obama tweet, which he said “raises the awareness of consensus” and “really helps in getting that information out into the general public.”

There is a consensus of evidence that human activity is causing all of recent global warming. Not some of it. Not even most of it. All of it.

Numerous studies have quantified the human contribution to global warming since the mid 20th century. Most estimates cluster around 100 percent. In fact, the best estimate is slightly over 100 percent. Various natural factors such as changes in solar activity, volcanoes, and wobbles in the Earth’s orbit have likely contributed slight cooling in recent decades.
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Based on this evidence, around 97 percent of climate scientists agree that humans are causing global warming. Again, this estimate isn’t based on a single survey. Rather, it’s based on a number of studies using a variety of independent methods. This includes surveys of scientists, analysis of public statements by scientists, and analyses of peer-reviewed climate research.

I co-authored a synthesis of the studies into scientific consensus on climate change. Two features jumped out at us from the research. First, as scientists’ expertise in climate science gets stronger, so too does their agreement that humans are causing global warming.

Second, among the scientists with the greatest expertise — climate scientists publishing climate research — there is 90 to 100 percent consensus with a number of estimates converging on 97 percent.
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That scientific agreement increases with climate expertise has been exploited by those looking to cast doubt on expert consensus. Unfortunately, it’s all-too-easy to mislead people into thinking that experts disagree on human-caused global warming. Just select a group of scientists with lower levels of expertise in climate science and portray their opinions as expert agreement. Or take it a step further and try it with non-scientists, which seems to work almost as well. If you want to work out whether you’re getting taken in with the fake-expert strategy, take a closer look at the “experts” who are being cited.

The most egregious example of the fake-expert strategy is the Global Warming Petition Project. This lists over 31,000 people with a science degree who signed a statement claiming that humans aren’t disrupting climate. This petition is held up as evidence against expert consensus on climate change. The flaw in this petition? Only 0.1 percent of the signatories actually have expertise in climate science. A mind-boggling 99.9 percent of the petition signatories are not climate scientists. This is fake experts in bulk.

This brings us Oren Cass’s cover story in the May 1, 2017, issue of National Review, “Who’s the Denier Now?” Before we get to consensus and fake experts, it’s instructive to begin where Cass begins — on the topic of the term “climate denier.” I agree with Cass that equating the rejection of climate science to holocaust denial is inappropriate. Rather, a less rhetorical and more evidence-based approach is to look to the scientific research into the phenomenon of science denial.

Science denial, as a behavior rather than a label, is a consequential and not-to-be ignored part of society. Denial of the link between HIV and AIDS caused hundreds of thousands of deaths in South Africa. Vaccination denial has allowed preventable diseases to make a comeback. When people ignore important messages from science, the consequences can be dire. And if we fail to understand how science denial works, that makes us vulnerable to being misled by the techniques of denial.

How do we recognize science denial? The various movements who have rejected a scientific consensus share the same five characteristics of science denial: reliance on fake experts, using logical fallacies to arrive at false conclusions, demanding impossible expectations of scientific proof, cherry picking from the full body of evidence and conspiracy theories to explain the consensus.

The various movements who have rejected a scientific consensus share the same five characteristics of science denial.

Psychology tells us something important about the five characteristics of science denial. While they may come across as nefarious tactics, they’re not always deliberately deceptive. The traits of denial can also result from unconscious, psychological biases. This means that deliberate deception can be indistinguishable from someone who genuinely believes false arguments.

By way of example, let’s return to the issue of fake experts. Psychological research finds that we tend to ascribe greater expertise to people we agree with. Think of when a person looks through someone else’s music or book collection and exclaims, “You’ve got great taste!” They’re really saying, “You’ve got my taste.”

This unconscious bias makes us vulnerable to reliance on fake experts when they express views we’re sympathetic to. This isn’t necessarily a malevolent strategy. It’s a natural human bias. This is one of the insights gleaned from the science of science denial.

Our 2016 survey-of-surveys warns against the fallacy of selecting samples of non-experts to cast doubt on expert consensus:

Low estimates of consensus arise from samples that include non-experts such as scientists (or non-scientists) who are not actively publishing climate research, while samples of experts are consistent in showing overwhelming consensus.

It’s with some degree of irony that Cass quotes figures from our survey-of-surveys to cast doubt on the consensus. He employs the very technique we warn against by using samples including non-experts.

For example, Cass cites 82 percent consensus. Let’s take a closer look at where he got this figure. It comes from a 2009 paper by Peter Doran and Maggie Zimmermann, who surveyed a broad group of Earth scientists. This included a variety of scientific disciplines with varying degrees of acceptance of climate change (unsurprisingly, the lowest agreement came from economic geologists). When Doran looked at scientists with the relevant expertise — climate scientists publishing climate research — he found 97 percent consensus.

Similarly, Cass cites a 2014 study (that I co-authored) as evidence that the expert consensus is 85 percent. Rick Santorum also misrepresented this study to cast doubt on the 97 percent consensus. Cass draws on a group that includes non-scientists who hadn’t published peer-reviewed climate papers. When we looked at the relevant experts — scientists who had published climate research — we found 90 percent consensus.

Overall, our survey-of-surveys found that across the different studies into consensus, expert agreement ranged between 90 to 100 percent. Moreover, we found a number of studies converging on 97 percent consensus. And it’s always important to come back to the fact that this consensus is built on a foundation of independent lines of empirical evidence.

When the evidence converges on a single coherent conclusion, affirmed by a scientific consensus, we can accept the science or we can deny it. How do we tell the difference between genuine scientific skepticism and science denial? The science of science denial identifies distinct, tell-tale characteristics of denial. Understanding those traits is essential to avoid being misled by misinformation.

— Dr. John Cook is a Research Assistant Professor at the Center for Climate Change Communication at George Mason University.