Our world leaders are presently meeting in Paris to discuss, quite literally, the fate of the world (see U.N. Climate Change Conference, COP21). Climate change undoubtedly represents one of the greatest challenges humanity has ever faced, given that it will impact virtually every aspect of our lives, including access to food and water, the spread of disease, the emergence of “climate refugees”, and so on. At these talks, there will undoubtedly be differences of opinion. World leaders will not only seek to reach consensus with each other, but will also have domestic audiences in mind. With the debate often framed (perhaps incorrectly) in ways that pit the environment against the economy (i.e., jobs), it is of little wonder that people hold divergent views on this pressing topic.

As I discussed in a recent column (click here), ideology matters a great deal, if not too much, to our thinking in modern society. Ideology was not associated with trust in science in the early 1970s, but it is now, with those on the political right increasingly distrusting basic science (for references, see my previous column). This is very much reflected in the modern discourse about climate change, with those on the right (vs. left) consistently more dismissive of the notion that climate change is happening or requires action (Campbell & Kay, 2014; Choma, Hanoch, Gummerum, & Hodson, 2013; Feygina, Jost, & Goldsmith, 2010; Guy, Kashima, Walker, & O’Neill, 2014; Hăkkinen & Akrami, 2014; Heath & Gifford, 2006; Kliegman, 2014; McCright & Dunlap, 2011; Lewandowsky, Oberauer, & Gignac, 2013; Rossen, Dunlop, & Lawrence, 2015; Tjernstrom & Tietenberg, 2008; van der Linden, Leiserowitz, Feinberg, & Maibach, 2015;Whitmarsh, 2011).

The left-right divide, in many of these studies, represents an effect size in the .40 range (as a correlation). This effect is moderate-to-large by conventional standards (see Cohen, 1988), considerably larger than the vast majority of effects or relations between variables observed in social psychology (Richard et al., 2003) or psychology (Fraley & Marks, 2007) (see also Hemphill, 2003). The political divide is therefore psychologically large and meaningful, and presumably represents a major obstacle in reaching consensus on climate change action.

But why is there such a sizeable left-right divide on climate change?

In a recent study led by my PhD student Mark Hoffarth, we surveyed 384 Americans to address this question (see Hoffarth & Hodson, in press). To measure political ideology we included several measures, including social dominance orientation (those scoring higher are more accepting of social inequality and group dominance), right-wing authoritarianism (those scoring higher are more conventional, submissive, and aggressive against norm violators), Republican versus Democrat identification, and liberal versus conservative self-rating. (this latter variable overlapped considerably with Republican vs. Democrat support so will not be discussed more in this summary; for related findings see Jost, 2006). The criteria we sought to predict from ideology were: support for environmental protection policies, climate change denial beliefs, and beliefs that climate change is not caused by human activity. As expected, those on the right (vs. left) were significantly more likely to deny climate change or support action to circumvent it.

We then statistically tested whether 4 variables potentially mediated (i.e., explained) the left-right divide on these criteria. These included: (1) utilization of nature (i.e., the belief that the environment is there to be exploited for human purposes, including beliefs about the priority of jobs); (2) dominance over nature (i.e., human superiority over the rest of nature); (3) love and care for nature. Of most relevance to our psychological investigation was (4): environmentalist threat, the belief that environmentalists represent a threat to our way of life, traditions, and customs. This measure was modelled on past research examining whether left-right differences in exploiting animals and consuming meat were also explained (in part) by vegetarian threat (see Dhont & Hodson, 2014; for related work, see MacInnis & Hodson, in press).

We predicted that much of the left-right divide would actually be explained by this pushback against environmentalists, over and above concerns for jobs (the aspect most openly discussed and rationalized by politicians). After all, some on the political right refer to environmentalists as “watermelons”, that is, green on the outside but secretly red (Communist/Socialist) on the inside. Others refer to environmentalists as Nazis or the Taliban, among other epithets. Such discourse represents pushback against those dedicated to the welfare of our planet, often at expense to themselves. Consider how President Jimmy Carter installed solar panels on the White house only to have them promptly removed by President Ronald Reagan (who also defunded research on alternative sources of energy). This was clear evidence of pushback; Reagan actually went to expense to have these panels removed rather than leave them as symbols of environmental stewardship. Consider also the activity known as “coal rolling”, whereby enthusiasts deliberately modify their vehicles to emit more pollution, presumably in opposition to the environmentalist movement. These represent actions against the perceived threats supposedly imposed by the green movement. The “Green Scare”, it appears, has replaced the “Red Scare” (Jacques, Dunlap, & Freeman, 2008).

The results of our analyses demonstrated that differences between those lower versus higher on social dominance orientation or authoritarianism were fully explained by the 4 mediating variables. The differences between Republicans and Democrats were partially explained by these variables. But the key take-home finding was that left-right differences were very much explained by perceptions of environmentalism threat (i.e., political pushback) among those on the right. Although economic concerns were a factor, they were much less relevant than the perception that environmentalists are bent on changing our way of life for their (presumably communist or socialist) agenda. This matters because politicians, particularly on the right, overtly argue that we can’t take action on climate change because such action would cost jobs. But such findings suggest that more of the resistance from the right may actually be based in intergroup opposition, specifically pushback against “tree-huggers”, relative to concern over jobs and the economy.

But these data also give reason to be hopeful. In our study we found no differences between liberals and conservatives, or between Republicans and Democrats, regarding love and care for nature. This certainly offers hope -- if those on the right care just as much about nature, they are an untapped resource (i.e., future advocates for saving the planet). The stakes are simply too high for us to be politically divided on this topic, particularly given the very high degree of consensus (above 95%) among the experts on climate change.

References and Suggested Readings:

Campbell, T. H., & Kay, A. C. (2014). Solution aversion: On the relation between ideology and motivated disbelief. Journal of Personality and Social Psychology, 107, 809-824.

Choma, B.L., Hanoch, Y., Gummerum, M., & Hodson, . (2013). Relations between risk perceptions and socio-political ideology are domain- and ideology- dependent. Personality and Individual Differences, 54, 29-34.

Dhont, K., & Hodson, G. (2014). Why do right-wing adherents engage in more animal exploitation and meat consumption? Personality and Individual Differences, 64, 12-17.

Feygina, I., Jost, J. T., & Goldsmith, R. E. (2010). System justification, the denial of global warming, and the possibility of “system-sanctioned change”. Personality and Social Psychology Bulletin, 36, 326-338.

Fraley, R. C., & Marks, M. J. (2007). The null hypothesis significance testing debate and its implications for personality research. In R. W. Robins, R. C. Fraley, & R. F. Krueger (Eds.), Handbook of research methods in personality psychology (pp. 149-169). New York: Guilford.

Gauchat, G. (2012). Politicization of science in the public sphere: A study of public trust in the United States, 1974 to 2010. American Sociological Review, 77, 167-187 DOI: 10.1177/0003122412438225

Gifford, R. (2011). The dragons of inaction: Psychological barriers that limit climate change mitigation and adaptation. American Psychologist, 66, 290-302.

Gifford, R. (2013). Dragons, mules, and honeybees: Barriers, carriers, and unwitting enablers of climate change action. Bulletin of the Atomic Scientists, 69, 41-48.

Guy, S., Kashima, Y., Walker, I., & O’Neill, S. (2014). The social psychology of climate change: Investigating the effects of knowledge and ideology on climate change beliefs. European Journal of Social Psychology, 44, 421-429.

Häkkinen, K., & Akrami, N. (2014). Ideology and climate change denial. Personality and Individual Differences, 70, 62-65.

Heath, Y., & Gifford, R. (2006). Free-market ideology and environmental degradation: The case of belief in global climate change. Environment and Behavior, 38, 48-71.

Hemphill, J.F. (2003). Interpreting the magnitudes of correlation coefficients. American Psychologist, 58, 78-79. DOI: 10.1037/0003-066X.58.1.78

[Hoffarth, M.R., & Hodson, G. (in press). Green on the outside, red on the inside: Perceived environmentalist threat as a factor explaining political polarization of climate change. Journal of . DOI: 10.1016/j.jenvp.2015.11.002. Paper now released with the following reference:]

Hoffarth, M.R., & Hodson, G. (2016). Green on the outside, red on the inside: Perceived environmentalist threat as a factor explaining political polarization of climate change. Journal of Environmental Psychology, 45, 40-49. DOI: 10.1016/j.jenvp.2015.11.002

Jacques, R. J., Dunlap, R. E., & Freeman, M. (2008). The organization of denial: conservative think tanks and environmental skepticism. Environmental , 17, 349e385.

Jost, J.T. (2006). The end of the end of ideology. American Psychologist, 61, 651-670. DOI: 10.1037/0003-066X.61.7.651

Kliegman, J. (2014). Jerry Brocn says ‘virtually no Republican’ in Washington accepts climate change science. Politifact. Retrieved from http://www.politifact.com/truth-o-meter/statements/2014/may/18/jerry-bro...

MacInnis, C.C., & Hodson, G. (in press). It ain’t easy eating greens: Evidence of toward vegetarians and vegans from both source and target. Group Processes and Intergroup Relations.

McCright, A. M., & Dunlap, R. E. (2011). Cool dudes: The denial of climate change among conservative white males in the United States. Global Environmental Change, 21, 1163-1172.

McCright, A. M., Dunlap, R. E., & Xiao, C. (2014). The impacts of temperature anomalies and political orientation on perceived winter warming. Nature Climate Change, 4, 1077-1081.

Pickering, G.J. (2015). Head in the (oil) sand? Climate change scepticism in Canada. Journal of Environmental and Social Sciences, 2, 117.

Richard, F.D., Bond, C.F. Jr., & Stokes-Zoota, J.J. (2003). One hundred years of social psychology quantitatively described. Review of General Psychology, 7, 331-363. DOI: 10.1037/1089-2680.7.4.331

Rossen, I. L., Dunlop, P. D., & Lawrence, C. M. (2015). The desire to maintain social order and the right to economic freedom: Two distinct moral pathways to climate change scepticism. Journal of Environmental Psychology, 42, 42-47.

Tjernström, E., & Tietenberg, T. (2008). Do differences in attitudes explain differences in national climate change policies? Ecological Economics, 65, 315-324.

van der Linden, S. L., Leiserowitz, A. A., Feinberg, G. D., & Maibach, E. W. (2015). The scientific consensus on climate change as a gateway belief: Experimental evidence. PLoS ONE, 10, 1-8.

Whitmarsh, L. (2011). Skepticism and uncertainty about climate change: Dimensions, determinants and change over time. Global Environmental Change, 21, 690-700.