Shifting public opinion on climate change : an empirical assessment of factors influencing concern over climate change in the U . S . , 2002 – 2010

This paper conducts an empirical analysis of the factors affecting U.S. public concern about the threat of climate change between January 2002 and December 2010. Utilizing Stimson’s method of constructing aggregate opinion measures, data from 74 separate surveys over a 9-year period are used to construct quarterly measures of public concern over global climate change. We examine five factors that should account for changes in levels of concern: 1) extreme weather events, 2) public access to accurate scientific information, 3) media coverage, 4) elite cues, and 5) movement/countermovement advocacy. A time-series analysis indicates that elite cues and structural economic factors have the largest effect on the level of public concern about climate change. While media coverage exerts an important influence, this coverage is itself largely a function of elite cues and economic factors. Weather extremes have no effect on aggregate public opinion. Promulgation of scientific information to the public on climate change has a minimal effect. The implication would seem to be that information-based science advocacy has had only a minor effect on public concern, while political mobilization by elites and advocacy groups is critical in influencing climate change concern. One of the earliest U.S. public opinion polls on global climate change was taken in July 1986, when the Cambridge Reports National Omnibus Survey asked individuals if they Climatic Change DOI 10.1007/s10584-012-0403-y Electronic supplementary material The online version of this article (doi:10.1007/s10584-012-0403-y) contains supplementary material, which is available to authorized users. R. J. Brulle (*) Department of Culture and Communications, Drexel University, Philadelphia, PA 19104, USA e-mail: brullerj@drexel.edu J. Carmichael Department of Sociology, McGill University, Montreal, Canada e-mail: jason.carmichael@mcgill.ca J. C. Jenkins Department of Sociology, Ohio State University, Columbus, OH, Canada e-mail: jenkins.12@osu.edu considered global warming a serious problem. Since then, nearly 300 different surveys have been performed on this topic, making opinions about the threat of climate change an expanding area of intense political (Pooley 2010) and academic (Krosnick et al. 2008; Kellstedt et al. 2008) interest. Along with this attention have come repeated calls for the creation of “political will,” based on the assumption that a shift in perception of this risk is the key to meaningful governmental and private action on climate change. Existing research on public opinion about global warming uses approaches derived from communications and social psychology that seek to determine which factors influence individual beliefs, knowledge, and action regarding climate change (Marquart-Pyatt et al. 2011). While useful, this approach neglects the larger cultural and political context that informs aggregate patterns of public opinion (Hindman 2009).When elected officials formulate their policy agenda, the aggregate distribution of public concern on various issues is a key consideration. Unless an issue is widely perceived as a major threat and/or a priority, it is unlikely to be on the agenda. Public concern about climate change has varied widely over the past few decades. For example, Gallup has been polling individuals about how much they personally worry about climate change. In 2004, 26% of the respondents stated that they worried “a great deal.” By 2007, this proportion had risen to 41%. But by 2010, this fraction dropped to 28%.Why?While this shift may be partially explained as individual attitude change, it seems more likely that broader climatic, cultural and political developments are responsible. We need to be able to consider such questions, including: Did media coverage, exposure to extreme weather, or scientific information at certain points in time contribute to greater or lesser concern? What about the mobilizing efforts of advocacy groups and elites, whose influence is often central to public perceptions of threat? An aggregate-level analysis is needed that can identify the informational, cultural and political processes that influence public concern about climate change. We begin our analysis with a discussion of how to measure aggregate public opinion, advocating Stimson’s (1999) method. Using all available national public opinion polls on climate change, we chart the quarterly changes in concern about climate change from 2002 through 2010. We then use time-series analysis to evaluate five explanations of climate change concern and conclude with a discussion about the implications for future efforts to influence public concern about the threat of global climate change. 1 Public opinion on climate change In the United States, climate change and environmental issues have consistently ranked at the bottom of public concerns as measured by polls. The most frequently used measure is the “Most Important Problem” question administered by the Gallup organization. Over the past 40 years during which environmental issues have been included in this scale, the overall response rate rarely exceeds 3%. Within subcategories of environmental concerns, global warming or global climate change is usually at the bottom. For example, in the March 2011 Gallup poll, environmental concerns were mentioned by only 1% of respondents as the most important problem facing the nation, and ranked 22nd overall. Among those mentioning environmental concerns, 79% worried a “great deal” or “fair amount” about toxic waste and water pollution. Out of nine environmental issues, global warming was ranked last, with only 51% of the public worried a great deal or a fair amount about this issue. An issue with a level of salience this low raises a question: Is the topic an actual concern of those polled, or simply a response constructed to conform to the options the survey offers? According to the Receive Accept Sample (RAS) model (Zaller 1992), individuals do not possess integrated true attitudes on most issues that are relatively peripheral to their Climatic Change