Why has U.S. public opinion on climate change fluctuated so much? Some scholars point to the quality of media coverage, others to local weather patterns or the communications capacity of scientific institutions. Whatever the cause, Gallup Surveys have shown significant swings in Americans’ concern about global warming: In 2004, 26% of respondents said they worried “a great deal” about the issue; in 2007 that number rose to 41%; by 2010, it had fallen to 28%. This variation comes despite consensus among scientists about the underlying data patterns and virtual unanimity of scientific opinion.
A 2012 study from Drexel University, McGill University and Ohio State University, “Shifting Public Opinion on Climate Change: An Empirical Assessment of Factors Influencing Concern over Climate Change in the U.S., 2002-2010,” sought to explain these variations in public opinion and isolate the key drivers. The study, published in the journal Climatic Change by researchers Robert J. Brulle, Jason Carmichael and J. Craig Jenkins, looked at weather, media and scientific communications patterns as well as economic and political factors.
The study’s key findings include:
- The most significant driver of public opinion on climate change was the battle between partisan elites over the issue. “The two strongest effects on public concern are Democratic Congressional action statements and Republican roll-call votes, which increase and diminish public concern, respectively. This finding points to the effect of [a] polarized political elite that is emitting contrary cues, with resulting (seemingly) contrary levels of public concern.”
- The decline in public worry about global warming coincided with political trends: “Beginning in 2008, the level of Republican anti-environmental voting increased progressively, reaching the highest level ever recorded in 2010. Whatever remained of the cooperation between Republicans and Democrats on environmental issues, and the subsequent elite cues provided by the Republican voting record, drove down climate change concern…. Additionally, unemployment increased, and GDP declined, following the 2008 financial collapse.”
- Efforts to improve mass communications and to promote reliable information “have a minor influence, and are dwarfed by the effect of the divide on environmental issues in the political elite.” In addition, “the effects of communication on public opinion regarding climate change are short lived. A high level of public concern over climate change was seen only during a period of both high levels of media coverage and active statements about the issue’s seriousness from political elites. It rapidly declined when these two factors declined.”
- The higher the level of media coverage on climate change, the greater public concern is. But the effect of larger volumes of coverage diminishes rapidly, and much coverage is “largely a function” of messages from politicians and economic factors.
- Weather events did not have a significant effect on public concerns about global warming. However, “that is not to say that individuals who experience disruptive weather events do not change their opinions regarding the threat posed by climate change.”
The authors conclude that the “more important factor at the aggregate level is the polarized positions taken by Democrats and Republicans. This polarization over environmental issues is long standing, and has extended to the climate change arena, making it a highly partisan issue. Given the vested economic interests reflected in this polarization, it seems doubtful that any communication process focused on persuading individuals will have much impact.”
In related research, a 2012 paper from Harvard’s Shorenstein Center, “Stories of Climate Change: Competing Narratives, the Media, and U.S. Public Opinion 2001-2010,” explores the communications dynamics around the issue.
Tags: global warming, campaign issue, climate politics
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