Earlier this year, we covered some polling data in which people were asked what factor shaped their acceptance of climate change. Buried in the data were two apparently contradictory findings: there is a large partisan divide in acceptance of climate change, but most respondents said they base their acceptance on their personal experience of the weather. Assuming that hot weather shows no partisan bias, this doesn't make much sense—political beliefs shouldn't influence what we think about the weather.

And yet they do. That's the conclusion of a new paper that dives into extensive polling data to find out how people perceive different trends in the climate. The results show that not all weather events are created equal. When it comes to things like flood and droughts, most people seem to have accurately registered the recent trends in their area. But when the subject shifts to temperatures, the actual trends become irrelevant, and ideology and political beliefs shape how people perceive things. As the authors put it, "the contentious nature of the climate change debate has influenced the way in which Americans perceive their local weather."

That authors of the study used data from about 8,000 poll responses, obtained between 2008 and 2011. The surveys included questions about how people perceived the weather in recent years. For temperatures, they were asked whether they were higher, the same, or lower than in past decades. Similar questions were asked about the frequency of floods and droughts. The survey also asked for self-assessments of political leanings, and included several questions that got at core ideological beliefs (such as egalitarian or individualist tendencies).

To link the survey results to the actual weather, the authors also obtained the zip code that the respondents called home. For each of these zip codes, the authors generated measures of recent weather (by averaging the last three years of temperatures and rainfall) and the typical climate, by obtaining the same average for the past 30 years. This allowed them to determine whether people from those zip codes were accurately perceiving the trends.

They checked this accuracy using two methods. For a simple analysis, they simply determined whether the perceived change in a measurement lined up with what actually took place. To get into the details, they performed a multivariate analysis to determine what factors were influencing how well a person's perceptions matched reality.

Both droughts and floods passed the simple test. These showed a clear trend in response to precipitation changes, and the trend was in the right direction—people perceived more floods and fewer droughts when there was more rain. And, in the statistical analysis, ideology and political affiliation had a weak effect on the accuracy of recollections, having about as much influence as education.

Things were completely different for temperatures. In fact, the actual trends in temperatures had nothing to do with how people perceived them. If you graphed the predictive power of people's perceptions against the actual temperatures, the resulting line was flat—it showed no trend at all. In the statistical model, the actual weather had little impact on people's perception of recent temperatures. Education continued to have a positive impact on whether they got it right, but its magnitude was dwarfed by the influences of political affiliation and cultural beliefs.

And those cultural affiliations had about the effect you'd expect. Individualists, who often object to environmental regulations as an infringement on their freedoms, tended to think the temperatures hadn't gone up in their area, regardless of whether they had. Strong egalitarians, in contrast, tended to believe the temperatures had gone up.

The authors conclude that climate change has become perceived as a form of cultural affiliation for most people: their acceptance of it is mostly a way of reinforcing their ties to the political and ideological communities they belong to. And, since temperatures have become the primary thing the public associates with climate change, people now interpret the temperatures through a filter based on their affiliations, a process termed "cultural cognition." In other words, we tend to interpret the temperatures in a way that reinforces our identity, and our connections with others who share similar political persuasions.

At the moment, however, this same sort of politicization hasn't occurred with things like droughts and floods, even though changes in precipitation are one predicted outcome of climate change. However, given the attention to the ongoing droughts in much of the country, this may only be true for a very narrow window.

Weather, Climate, and Society, 2012. DOI: 10.1175/WCAS-D-11-00044.1 (About DOIs).