Simple messages help set the record straight about scientific agreement on human-caused climate change: the results of two experiments

PLoS One. 2015 Mar 26;10(3):e0120985. doi: 10.1371/journal.pone.0120985. eCollection 2015.


Human-caused climate change is happening; nearly all climate scientists are convinced of this basic fact according to surveys of experts and reviews of the peer-reviewed literature. Yet, among the American public, there is widespread misunderstanding of this scientific consensus. In this paper, we report results from two experiments, conducted with national samples of American adults, that tested messages designed to convey the high level of agreement in the climate science community about human-caused climate change. The first experiment tested hypotheses about providing numeric versus non-numeric assertions concerning the level of scientific agreement. We found that numeric statements resulted in higher estimates of the scientific agreement. The second experiment tested the effect of eliciting respondents' estimates of scientific agreement prior to presenting them with a statement about the level of scientific agreement. Participants who estimated the level of agreement prior to being shown the corrective statement gave higher estimates of the scientific consensus than respondents who were not asked to estimate in advance, indicating that incorporating an "estimation and reveal" technique into public communication about scientific consensus may be effective. The interaction of messages with political ideology was also tested, and demonstrated that messages were approximately equally effective among liberals and conservatives. Implications for theory and practice are discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Climate Change*
  • Human Activities*
  • Humans

Grant support

This research was funded by the Grantham Foundation for the Protection of the Environment, the Rockefeller Family Fund (RFF), as well as by Lawrence Linden, Robert Litterman and Henry Paulson. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.