We are pleased to announce a newly published article: "The Scientific Consensus on Climate Change as a Gateway Belief: Experimental Evidence" by Sander van der Linden, Anthony Leiserowitz, Geoffrey Feinberg and Edward Maibach in the journal PLoS ONE.
Our prior survey research has found that only one in ten Americans (9%) correctly understands that there is a scientific consensus about human-caused climate change - i.e., that nearly all climate scientists are convinced that human-caused climate change is happening. Our new article reports the results of an experiment that investigated how people respond when informed about the scientific consensus.
The paper tested a theoretical model that has practical implications for public engagement. In short, we posited that people's beliefs about the level of scientific consensus act as an important "gateway belief" by influencing their other key beliefs about climate change (i.e., whether or not climate change is happening, human-caused and a worrisome threat that requires more public action). Furthermore, we tested whether informing people about the scientific consensus increases their perception of the scientific consensus, and whether that increase subsequently influences their other key beliefs about climate change (i.e., that it is happening, human-caused, and worrisome) and, in turn, their support for public action.
Our results provide strong evidence for a gateway belief model. On average, being exposed to a "consensus-message" increased study participants' perceptions of the scientific consensus by 12.8%, and up to as much as 20% in some conditions (compared to a control group). Moreover, this substantial change in the perceived level of scientific consensus caused a positive shift in participants' belief that climate change is happening, human-caused and a worrisome threat. Changes in these beliefs, in turn, increased support for public action. Importantly, we found these effects for both Democrats and Republicans.
Our experiment used a very simple message and just a single exposure to that message. Practically, this suggests that a concerted campaign to repeatedly communicate the scientific consensus, using a variety of trusted messengers, is likely to improve public understanding and engagement with the issue.
It is also worth noting that the neutral, scientific character of the message did not cause further political polarization on the issue. Many people use expert consensus as a heuristic to guide their decisions across a wide range of domains, from health (e.g., smoking) to financial planning. In short, improving public understanding of the scientific consensus that human-caused climate change is happening has the potential to improve public acceptance of the findings of climate change science and consequently, increase support for climate policy.
March 07, 2015