Eliminating the local warming effect

A growing body of work shows that perceived deviations in daily local temperatures alter individuals’ global warming beliefs and concerns (e.g., Krosnick et al. 2006, Semenza et al. 2008, Li et al. 2011, Zaval et al. 2014). Little research, however, explores the conditions under which this “local warming” effect occurs. Here, Druckman presents an experiment that shows how a simple prompt—that reminds individuals to remember how the weather felt over the past year—eliminates the local warming effect. Specifically, the prompt severs the relationship between perceptions of the daily temperature with estimates of last year’s temperature deviations, which is the basis on which many base their global warming opinions. While the results do not reveal the frequency that local warming effects occur overall, they do demonstrate the limits of the effect. Additionally, the findings suggest ways to rhetorically counteract the effect. Public opinion about the existence and salience of global warming plays an important role in the construct of public policy. Elected oriented politicians rarely implement new policies in the face of public opposition. A sizable literature has sought to explain the origins and nature of global warming opinions. One notable finding is that individuals often base their beliefs about global warming on their present assessments of local temperature: relatively warm temperatures lead individuals to increase their belief in and concern about global warming. Egan and Mullin (2014: 89) state that the “evidence for the effect of weather on public opinion regarding climate change is now overwhelming.” Perhaps the most compelling demonstration of the “local warming” phenomenon comes from Zaval et al. (2014). The authors present a series of ingenious studies that show, rather conclusively, that when individuals perceive the day’s local temperature to be warmer than usual, they then overestimate the number of warm days through the year, which, in turn, leads them to increase their beliefs about the existence of global warming and their concern about global warming (also see, e.g., Krosnick et al. 2006, Semenza et al. 2008, Li et al. 2011). Moreover, information about the distinction between weather (e.g., a constantly changing dynamic) and climate (e.g., average weather over time and space), or changes in terminology (e.g., global warming versus climate change) do not vitiate the impact of local temperatures on beliefs. The effect is substantively significant, rivaling the impact of age, race, and education on global warming attitudes (Egan and Mullin 2012: 796). For many this dynamic is concerning; Egan and Mullin (2012: 806) state, “[g]lobal climate change is one of the most important public policy challenges of our time... [people] use fluctuations in local temperature to reassess their beliefs about the existence of global warming... a discovery 1 Others find mixed evidence on the impact of climate changes on beliefs; however, much of the inconsistent evidence concerns actual and not perceived climate shifts: “studies tend to find that perceptions of weather have greater influence on climate change perceptions than do actual weather” (Marquart-Pyatt et al. 2014: 249).