Global warming scepticism and luxury materialism

I recently came across a paper (Walasek & Brown, 2015, Psychological Science) that documents an association across US states between income inequality and Google searches for status goods (e.g., "ralph lauren mens"). In other words, searches for status goods were relatively more common in states with higher income inequality. The authors interpret this as evidence that people become more concerned about social rank when income inequality is greater.

After reading the paper, I was playing around with Google Correlate when I noticed a strong negative association between searches for "global warming myth" and searches for status goods. To be systematic, I downloaded Google Correlate data for each of 15 status goods (comprising 5 luxury fashion brands, 5 luxury jewellery brands, and 5 luxury car brands): "ralph lauren", "gucci", "louis vuitton", "burberry", "prada", "bvlgari", "cartier", "tiffany", "rolex", "omega", "ferrari", "lamborghini", "porsche", "aston martin" and "maserati". The first principal component from a PCA on these 15 search terms explained 69% of the variance, and the screeplot strongly suggested a single dimension in the data. I also downloaded the Google Correlate data for "global warming myth" and "global warming hoax", and took an average across these two search terms (they were correlated at r = .94, p < 0.001).

The chart below plots global warming scepticism against luxury materialism (i.e., the principal component from the 15 search terms) for all 51 states. The relationship is strongly negative, namely r = –.76 (p < 0.001). Unsurprisingly perhaps, New York is the most materialistic state. And Wyoming is the state most sceptical about global warming. In general, red states tend to be more sceptical about global warming, while blue states tend to be more materialistic. Obama vote share in 2012 is correlated at r = –.48 (p < 0.001) with global warming scepticism and at r = .49 (p < 0.001) with luxury materialism.

To check the robustness of the relationship, I adjusted for the following variables using multiple linear regression: log GDP per capita, median income, urbanisation, log energy use per capita, Gini coefficient, Obama vote share, and fracking state. Standardised coefficients are given in the table below. Luxury materialism remains strongly and significantly associated with global warming scepticism after adjusting for these variables.

The negative association between global warming scepticism and luxury materialism is at least somewhat unexpected. One might have thought people with a taste for superfluous luxury goods would be more sceptical about a phenomenon that has led to calls for massive reductions in human consumption. Aside from the obvious possibility of an ecological fallacy, a caveat is that luxury materialism is not necessarily equivalent to mass consumerism, or indeed ecological impact. In fact, log energy use per capita is positively correlated with global warming scepticism (r = .45, p < 0.001), and negatively correlated with luxury materialism (r = –.55, p < 0.001). Yet statistically, energy use per capita does not seem to account for the association between global warming scepticism and luxury materialism.

I have no straightforward explanation for the association. I'd be interested to hear if anyone else has one.