What inferences can be drawn from *empirical evidence* about the science-communication impact of using the term "climate change denier"?
Andy "dotearth" Revkin, the Hank Aaron of environmental-science journalism, posted this question after a colloquy with other thoughtful science communicators. Andy apparently was moved to ask it after observing a talk on climate change by "science guy" Bill Nye.
Here is my answer. I invite others to supplement!
As is so for climate change, sometimes positions on a risk or other policy-consequential fact become publicly recognizable symbols of membership in opposing cultural groups. When that happens, members of those groups are likely to judge the expertise of any science communicator who is addressing that risk based on whether they see him or her as aligned with or hostile to their own group. E.g., see
1. Corner, A., Whitmarsh, L., & Xenias, D. Uncertainty, scepticism and attitudes towards climate change: biased assimilation and attitude polarisation. Climatic Change, 1-16. doi: 10.1007/s10584-012-0424-6
2. Kahan, D., Braman, D., Cohen, G., Gastil, J., & Slovic, P. (2010). Who Fears the HPV Vaccine, Who Doesn’t, and Why? An Experimental Study of the Mechanisms of Cultural Cognition. Law and Human Behavior, 34(6), 501-516.
This helps explain why even people who are pro-science & who believe science should inform public policy generally can polarize on a policy-consequential fact that admits of scientific evidence (an effect that persists even among highly science literate members of opposing groups).
Accordingly, whether or not he "alienates" anyone, I think when someone like Bill Nye speaks about "climate change deniers" he creates the foreseeable risk that many ordinary people, including many reflective and open-minded ones, will not view him as credible. "Climate denial," for them, is likely to be a cue that causes them to perceive Nye (perhaps rightly, but perhaps wrongly) as aligned with a cultural group that harbors animosty toward their own. They will thus not view him as a genuine (or at least not as a trustworthy) "expert" but instead seem him as a partisan. Consistent with Brendan Nyhan's recent study, exposure to Nye's advocacy might even intensify the strength with which ordinary people are committed to the position he is attacking.
These are conjectures, extrapolations from the results of studies that are in effect models of how people process information in such settings. One could test my view by taking a recording of Nye's remarks and showing it to a general population sample. If those who observed him became more culturally polarized relative to a control group who didn't see Nye's remarks, that would be evidence supportive of the hypothesis I just offered, whereas if they didn't polarize or even started to converge relative to the control group, that would be evidence the other way. I'm happy to advise or collobarate w/ anyone who would like to do the study (including Bill Nye, provided he gives me one of his cool ties).
Such a test would still only be a model, btw, from which conclusions about how to talk to whom about what (assuming one actually wants to have a meaningful exchange of ideas with someone) would still depend on inferences reflecting information, evidence, beliefs, etc. independent of the study itself. That's the way things are, always and on everything that one can study with empirical methods (this is obvious but it bears repeating -- over & over & over -- because many people have the unscientific view that scientific studies "prove/disprove" propositions & "demonstrate" the wisdom of courses of action in some way that obviates the need to rely on judgment and reason, not to mention the need ever to consider any more evidence ever again).