“I didn’t pull punches” in pointing out the “gravity” of climate challenges, a Colorado State professor says of his exchanges with a Heartland Institute conference of climate doubters. He would do it all over again and hopes his “like-minded” colleagues will do so too, and he offers lessons-learned.

It’s news when a climate scientist convinced of the evidence relied on by a group like IPCC goes head-to-head against climate “contrarians” before a public audience.

Denning: High road? But High Road to Where?

It’s a practice many of the “consensus” scientists studiously avoid, saying they fear elevating an unjust adversary they regard as being often motivated more by political and policy concerns than by a commitment to scientific evidence. Colorado State University atmospheric sciences professor Scott Denning took just such a plunge, however, and with his eyes fully open. And he says he’d do it again and hopes his like-minded colleagues also will.

Denning wrote recently in the UCAR Magazine of his experiences speaking before the annual conference sponsored by the climate-doubtful Heartland Institute in Washington, D.C.

“I was treated with respect and even warmth despite my vehement disagreement with most of the other presenters,” Denning wrote, expressing thanks for prominent platforms he was provided during the conference, including an hour-long keynote debate with contrarian Roy Spencer of the University of Alabama, Huntsville.

Change Minds? Rather, Defuse Rhetoric

Asked if he had accepted the Heartland Institute speech invitation with the idea of “changing some minds,” Denning paused before responding, “Yeh. I guess I did. I hoped to change some minds,” but he added that “a lot of people” at the conference were “not so open-minded.” At the same time, he said he was gratified by the number of conferees who later told him that his remarks “really made me think.” He pointed to a long dinner discussion he had with a former New Zealand environmental minister and “hard-core climate denier” who asked “really insightful questions.”

“These were not a bunch of brain-washed idiots,” Denning said of the conferees, rebutting an impression many in the science community might have. He said his real goal in making his remarks, rather than changing minds, was more along the lines of “diffusing the angry rhetoric on both sides” through, for instance, what he called the “rhetorical tricks” of beginning on “common ground” and of emphasizing facts “that are not in dispute.”

Prior to making his remarks at the Heartland meeting, Denning said he had been getting a ratio of three-to-one comments from fellow scientists that his planned presentation to such an audience would likely backfire. Since posting his UCAR Magazine piece, he said, comments from his “like-minded” science peers have been overwhelmingly favorable and upbeat.

High Road? … High Road to Ruin?

Denning in his article dismissed claims of many scientists that avoiding such head-to-heads with committed climate contrarians amounts to the “high road.” Citing polling showing increased public uncertainties about climate change, he wrote that he fears “the high road to ruin.”

“Strong and persuasive engagement” of contrarians by bona fide experts “articulating the scientific consensus is essential,” he wrote. He urged avoiding jargon, complicated graphics with unreadable titles “and unintelligible lines that look like multicolored spaghetti.”

Denning characterized the Heartland conference audience as having “a strong and obvious identification with libertarian and free-market ideology” and said many in the audience appear to see predictions of risks from climate change as “a stalking horse for intrusive government policies.” He wrote that he countered that “the world needs their ideas to solve one of the most pressing problems humanity has ever faced …. I didn’t pull any punches.” Dozens of participants “told me they’d needed to hear this ‘other side’ of the story of climate change.”

Tips for Being ‘Informative, Persuasive, Productive’

Outlining some lessons-learned from his Heartland conference experience, Denning suggested “informative, persuasive, and productive” approaches such as:

• Beginning from “common ground,” such as recognizing a need for public policy to be based on facts rather than on political agendas;
• Engaging a skeptical audience “on a human level,” including using humor and ordinary examples from daily life; and
• Emphasizing “the basics” and points “not in dispute,” such as basic physics points about CO₂ and about combustion of fossil fuels.

“Taken together, these indisputable facts lead to the conclusion that continued burning of fossil fuels will warm the climate,” Denning wrote. “You don’t have to believe experts, and there doesn’t have to be an overwhelming consensus behind them. It just makes sense for the same reason that a teapot placed on a hot stove will get hot.”

Denning’s Views on Pitfalls to Avoid

An example of “what doesn’t work” in speaking with audiences such as those at the Heartland conference, Denning wrote, “is the condescending argument from authority that presumes that the Earth’s climate is too complicated for ordinary people to understand, so that they have to trust the opinions of experts.”

“Appeals to ‘overwhelming scientific consensus’ are more likely to confirm the audience’s suspicions of some kind of nefarious conspiracy than to change minds,” Denning wrote, and “even the concept of peer review can sound sinister.”

Denning concluded by acknowledging “a huge gap” on what he called “the gravity of the climate problem.”

“It will take the committed and respectful participation of mainstream climate scientists in settings that may lie outside their comfort zones,” and he said he hopes more “like-minded colleagues” will take that plunge.