Could geoengineering cool the climate change debate?

Geoengineering (according to the National Academy of Sciences) “refers to deliberate, large-scale manipulations of Earth’s environment designed to offset some of the harmful consequences of [greenhouse-gas induced] climate change.” But what impact might the advent of this emerging technology have on the science-communication environment in which the public makes sense of the evidence for climate change and its significance?

Geoengineering is still very much at the drawing board stage, but the sketches of what it might look like—from solar-reflective nanotechnology flying saucers to floating mist-emitting “cloud whiteners”—are pretty amazing.

The U.S. National Academy of Sciences and the Royal Society in the U.K. are among the preeminent scientific authorities that have called for stepped up research efforts to develop geoengineering—and to assess the risks that it might itself pose to the physical environment.

Also very much in need of research (and getting it from an expert UK team that includes Nick Pidgeon) are the science-communication challenges that geoengineering is likely to confront.

Indeed, anxiety over the impact that geoengineering could have on public opinion is now putting research into the underlying science at risk.

All the issues surrounding geoengineering, including the ethical ones, obviously demand open public deliberation.

But critics oppose even permitting research to begin lest it lull the public into a state of false security that will enervate any support for carbon emission limits—a dynamic labeled (mislabeled really, given the well-established and familiar technical meaning of the term in economics) the “moral hazard” effect.

Political resistance fueled by this argument resulted in postponement of a very rudimentary scientific experiment (one involving the operation of a high-pressure water hose attached to a helium balloon) that was supposed  to be conducted by scientists at Cambridge University last fall.

CCP recently conducted a study to see what impact geoengineering might have on the science-communication environment. We found no support for the “moral hazard” hypothesis.  Indeed, the study, which was conducted with both US and UK subjects, found that geoengineering might well improve the quality of public deliberations by reducing cultural polarization over climate change science.

The study involved an experiment in which subjects assessed a scientific study on climate change. The study (a composite of two, which appeared in Nature and Proceedings of the National Academies of Sciences) reported researchers’ conclusion that previous projections of carbon dissipation had been too optimistic and that significant environmental harm could be anticipated no matter how much carbon emissions were reduced in the future.

The subjects, all of whom read the dissipation study, were divided into three groups, each of which was assigned to read a different mock newspaper article. Subjects in the “anti-pollution” condition read an article that reported the recommendation of scientists for even stricter CO2 limits. Subjects in the “geoengineering condition” read an article that reported the recommendation of scientists for research on geoengineering, on which the article also supplied background information.

Finally, a “control condition” group read an article about a municipality’s decision to require construction companies to post bonds for the erection of traffic signals in housing developments.

Logically speaking, what one proposes to do about climate change (implement stricter carbon emission limits, investigate geoengineering, or even put up more traffic signals) has no bearing on the validity of a scientific study that purports to find that climate change is a more serious problem than previously had been understood.

But psychologically one might expect which newspaper article subjects read to make a difference. The “moral hazard” argument, for example, posits that information about geoengineering will induce members of the public to discount the seriousness of the threat that climate change poses.

That’s not what we found, however. Indeed, contrary to the “moral hazard” hypothesis, subjects in the geoengineering were slightly more concerned than ones in the anti-pollution and control conditions.

We also found that the experimental assignment affected how culturally polarized the study subjects (in both countries) were. The subjects in the anti-pollution condition were the most polarized over the validity of study (whether computer models are reliable, whether the researchers were biased, etc.); subjects in the geoengineering condition were the least.

 We had hypothesized this pattern based on cultural cognition research.

That research shows that individuals tend to form perceptions of risk that fit their values. Thus, egalitarian communitarians, who are morally suspicious of commerce and industry, find it congenial to believe those activities are dangerous and thus worthy of regulation. Hierarchical individualists, in contrast, tend to be dismissive of environmental risk claims, including climate change, because they value commerce and industry and perceive (unconsciously) that such claims will result in their being restricted.

These meanings were reinforced by the newspaper article in the anti-pollution condition, resulting in the two groups becoming even more divided in that condition on the validity of the carbon-dissipation study.

But the information on geoengineering, we posited, would dissipate the usual cultural meanings associated with climate change science. Because it shows that there are policy responses aside from restricting commerce and industry, information on geoengineering reduces the threat that evidence of climate change poses to hierarchical individualist sensibilities and thus the psychic incentive to dismiss that evidence out of hand.

This conjecture was the basis for predicting the depolarization effect actually observed in the geoengineering condition.

What’s the upshot?

Well, certainly not that geoengineering should be embraced as a policy solution to climate change. Whether that’s a good idea depends on the sort of research that the Royal Society and National Academy of Sciences have proposed.

Moreover, although this study furnishes evidence that engaging in that sort of research—and inviting public discussion of its implications—will actually improve the science communication environment, rather than harm it as the “moral hazard” position asserts, that proposition, too, certainly merits further research.

But the one conclusion I think can be made without qualification is that claims about the impact of scientific research on public risk perceptions, just like ones about the impact of human activity on the environment, admit of scientific investigation.

When predictions of adverse public reactions are not only advanced without any supporting evidence but also asserted as decisive reason to block scientific inquiry, there should be little doubt that those making them lack a genuine commitment to the principles of science.


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