Climate change sceptic films more influential than advocacy films, claims study

Eminent scientists have condemned films that are sceptical about climate change. After airing of the Great Global Warming Swindle in 2007, for example, Sir Martin Rees, President of the Royal Society at the time, said "those who promote fringe scientific views but ignore the weight of evidence are playing a dangerous game."

Of course there are also films that affirm the idea that human activity has contributed to the rise in global temperatures – Al Gore's An Inconvenient Truth is probably the most well known. Unfortunately for environmentalists and people who believe global warming is a threat, a new study claims that sceptical films have a more powerful influence on viewers' attitudes than climate change advocacy films.

Tobias Greitemeyer recruited 97 students at the University of Innsbruck. Thirty-three of them watched the climate change affirming film Children of The Flood – a futuristic tale depicting the life-threatening impact of melted ice-caps. Thirty-six watched The Great Global Warming Swindle, which challenges the idea that global warming is affected by human activity. The remainder acted as controls and watched a neutral film Forgotten Country in The Mekong Region, about life in Laos. The participants watched the first 15 minutes of each film.

Although the students were allocated randomly to the different conditions, those who watched the sceptic film subsequently reported more negative attitudes toward the environment than those who watched the neutral film or the affirming film. By contrast, there was no difference in attitudes to the environment between students who watched the neutral film and those who watched the affirming film.

A second study was similar but this time 92 students watched either Six Degrees Could Change the World (climate change affirming); The Climate Swindle: How Eco-mafia Betrays Us; or Planet Earth: Caves (a neutral film). Also, Greitemeyer added in a questionnaire about participants' concern for the future.

This time participants who watched the sceptical film ended up with greater apathy towards the environment as compared with participants who watched the neutral or affirming films, an outcome that was mediated by their having reduced concern for the future in general. This was the pattern both for participants who tended to engage in pro-environment behaviours in their everyday lives and those who didn't so much. As in the first study, there were no differences in post-viewing environment attitudes between those who'd watched the affirmative or neutral films.

When it comes to a lack of belief in the human causes of global warming, Greitemeyer said his results suggest "the media are part of the problem, but may not easily be used to be part of the solution." He thinks sceptical films have a negative influence on people's attitudes, but that films advocating for the human impact on climate change are ineffectual.

Unfortunately his claims are undermined by the limitations of the study. Above all it's unfortunate that he didn't measure his participants' baseline attitudes. This means we can't get any idea of the size of the influence of the films and we have to trust on faith that the randomisation to conditions was effective (i.e. that students in the different film conditions didn't differ in their attitudes before watching the films). There is also a question mark over how much the results would generalise to a non-student sample.

Indeed, in a subsequent survey of different students at the same uni, Greitemeyer found that they had an overwhelming bias towards believing in the reality of human effects on global warming. Therefore, perhaps the sceptical films appeared to be more influential because they contradicted students' pre-existing beliefs whereas the affirmative films told the students only what they already knew. A final limitation is the lack of analysis of the content of the films – we don't know what the active ingredients might be nor whether these were found equally in sceptical and affirmative films.

Further reading

Tobias Greitemeyer (2013). Beware of climate change skeptic films. Journal of Environmental Psychology DOI: 10.1016/j.jenvp.2013.06.002