Americans seem to conflate local temperatures with global trends, researchers find.
By Nathan Collins
(Photo: Khuroshvili Ilya/Flickr)
The scope of climate change is not always easy to communicate. For one thing, there’s a time-scale problem: The pace of global warming is fairly slow relative to year-to-year temperature differences. That’s compounded by the fact that we don’t experience planetary climate change—at best, we’re aware of local trends, not global ones. Indeed, Americans’ beliefs about climate change seem to be more influenced by their local weather than global trends, according to a study published this week in Proceedings of the National Academy of Sciences.
“We find that skepticism about whether the Earth is warming is greater in areas exhibiting cooling relative to areas that have warmed and that recent cooling can offset historical warming,” Robert Kaufman and his colleagues write. “This experiential basis for skepticism of climate change identifies obstacles to communicating ongoing changes in climate to the public and how these communications might be improved.”
To reach that conclusion, Kaufman and his team first gathered temperature data from weather stations around the United States that had data going back at least 30 years. For each station, they computed a rough measure of climate change based on the number of days in the year on which the record high was more recent than the record low. (For example, the record high for Seattle on December 21st occurred in 2014, while the record low for December 21st was in 1990, so the record high for Seattle on December 21st is more recent than the record low.)
By that rough measure, nearly half of the areas the team looked at had warmed considerably, although about 10 percent had cooled off, setting the stage for the more important question: Did warming versus cooling trends affect individuals’ beliefs about climate change?
In short, yes. At the county level, climate differences led to a ±4 percent change in the percentage of adults in a county that believed climate change was real. In other words, in parts of the U.S. where it’s getting colder—where the record lows are more recent than record highs—people are less likely to believe what scientists tell them about climate change.
“The importance of experiential learning creates several challenges to a public consensus needed to implement meaningful climate change policy,” the researchers write. “In places where the weather actually is cooling over time, contradictions between personal experiences with local changes in climate and the scientific evidence for climate change seem settled in favor of personal experience. Changing this weighting in favor of scientific evidence will be difficult given the importance of personal experience.”