The legitimacy of environmental scientists in the public sphere

Abstract

Previous research has examined public perceptions of climate change, including opinions about the severity of its effects, whether it is human caused, the degree of its exaggeration in the news media, and the level of scientific consensus on the issue. This research has shown that public beliefs about each of these aspects of climate change are politically charged. What remains understudied are the sources of environmental scientists’ authority in the broader society and whether perceptions of environmental scientists themselves are polarized. Using data from the General Social Survey’s Science and Technology Module, this study fills this gap in knowledge by examining public perceptions of environmental scientists across several dimensions. We develop and formally test a theoretical model of the legitimacy of environmental scientists in the public sphere, as measured by public support for their influence on climate policy. Consistent with other research on public beliefs about climate change, we find that perceptions of environmental scientists are polarized across multiple measures. Moreover, while previous theory and research have emphasized beliefs about scientific consensus on climate change, we find that perceptions of scientists’ understanding of the issue and the integrity of their policy advice are each stronger predictors of scientists’ legitimacy in the public sphere.

Appendix

Outcome variable. Respondents were given a brief statement that described the debate surrounding global warming: Global warming means a trend toward warmer temperatures throughout the world, with more extreme weather in many places and changes in food production that could affect our way of life. Some people believe that the burning of gasoline and other fossil fuels causes global warming. Others say that global warming has purely natural causes. To measure scientists’ legitimacy as policy advisors, respondents were asked to rate on a four-point scale how much influence environmental scientists should have in deciding what to do about global warming. In our analysis, higher scores are coded to mean more influence.

Mediator variables. Respondents were also asked to respond to the following three questions on five-point scales: (1) How well do environmental scientists understand the causes of global warming? (2) When making policy recommendations about global warming, to what extent do you think environmental scientists would support what is best for the country as a whole versus what serves their own narrow interests? (3) To what extent do environmental scientists agree among themselves about the existence and causes of global warming? Responses are coded so that higher values correspond to greater perceived understanding, more support of the nation’s best interests, and greater agreement among scientists.

Analytical technique. SEMs are ideal for this analysis, because they can simultaneously estimate a CFA, accommodate mediating factors, and allow for omnibus tests of alternative models simultaneously included in the system of equations (Hoyle 2012). In addition, unlike simple regression models, mediator variables are allowed to covary in the SEM format, reducing overall error in the model. All models were computed using Mplus 7.14 statistical software. Because our endogenous variables are categorical, we estimate our SEM using diagonally weighted least squares. Fit statistics, including the RMSEA, CFI, and TLI, indicate an excellent fit between the model and the data. Complete estimates for the SEM are contained in Supplemental Table A3.