Geoengineering comprises technologies designed to counteract human-caused climate change: towering “carbon scrubbers” that would suck carbon dioxide from the atmosphere; the injection of iron pellets into the ocean to stimulate growth of carbon-consuming phytoplankton blooms; or — my personal favorite— deploying zillions of mirror-coated nanotechnology flying saucers to form a stratospheric solar reflector.
Would such technologies cool the planet enough to stave off the devastating consequences scientists predict if global warming is not contained?
But the NAS proposal might help reduce the simmering temperature of the U.S. climate debate enough to enable constructive public deliberations. The reason is in another study that appeared last week, this one in the Annals of the American Academy of Political and Social Science.
In this study, my collaborators Hank Jenkins-Smith, Tor Tarantola, Carol Silva, Donald Braman and I examined how information about geoengineering might counteract the impact of cultural cognition.
Cultural cognition refers to the tendency of individuals to selectively credit all manner of information — from logical arguments to empirical data; from expert opinion to their own sense impressions — in patterns that support their values.
For example, citizens who prize individual self-sufficiency tend to dismiss claims of environmental risk because accepting these claims would license restrictions on free markets. Citizens who favor stable and clearly defined social rankings tend to see environmentalism as an implicit indictment of social elites.
By contrast, citizens with more egalitarian and communitarian commitments tend to be suspicious of commerce and industry, which they blame for unjust social disparities. They will believe evidence that industries threaten public health and should be regulated on that basis.
In our research, we asked people to evaluate a study about climate change. The study was a composite based on real ones that find that carbon dioxide dissipates from the atmosphere more slowly than had been previously realized. As a result, even if nations adopt the most ambitious proposed limits on atmospheric carbon dioxide, there would still be massive inundation of coastal regions, dust-bowl conditions in Europe and North America, and myriad other catastrophic effects.
In the first condition of the experiment, people examined the climate-change study after first reading an unrelated news report about a city council meeting on traffic signals.
In the second condition, people first read a news report that suggested leading scientists had called on nations worldwide to adopt stricter carbon dioxide emissions.
In the third condition, people first read a news report announcing that a leading scientific body — very much like the NAS — had called for more research into geoengineering.
Logically speaking, the information in the second and third conditions was no more relevant to assessing the validity of the climate change study than was the information in first condition. But psychologically, the news reports mattered a great deal.
In the first condition, there was predictable evidence of cultural cognition: People with egalitarian and communitarian worldviews readily credited the climate change study, while those with more hierarchical and individualistic worldviews dismissed it.
The call for stricter carbon dioxide restrictions featured in the anti-pollution news report made these tendencies even worse. By triggering antagonistic associations between climate change and free markets, this news report increased polarization among people with different world views.
The call for geoengineering, however, had a very different effect. The idea that human ingenuity is itself up to the task of managing the environmental risks that human ingenuity creates is a historical theme that powerfully resonates with persons who have individualistic and hierarchical outlooks. And so we predicted that substituting this identity-affirming “yes we can” narrative for the denigrating “we told you so” one, which animates many climate change policy messages, would mitigate rejection of the evidence among the people most predisposed to do so.
That’s what we found. The call for geoengineering made subjects with hierarchical and individualistic values react less dismissively toward the study. As a result, polarization decreased among people who read the anti-pollution news report.
Our study, therefore, calls into doubt the argument of commentators who warn that exploring geoengineering could lull the public into a sense of complacency on climate change. We found that those who first read about geoengineering were the most concerned about the dangers of global warming.
Of course, there is no guarantee that the effects we observed in this experiment would emerge if we could confront people with similar messages. (We are working on this, however.)
Nevertheless, our study suggests that it would be foolish — not to mention awkward — for those who care about climate change to deny that geoengineering research is exactly what scientific consensus recommends.
Dan M. Kahan is the Elizabeth K. Dollard Professor of Law and Professor of Psychology at Yale Law School.
This post is part of our series on science and politics. The introduction to the series is here.