A new statistical model grinds national poll data about climate change as finely as any pepper mill, and it can predict the public's climate change beliefs, risk perceptions, and policy preferences right down to the level of each state, county and congressional district, its authors say.
But the arrival of this Big Data tool may not produce many big surprises.
It predicts, for example, that people from Trimble County, Kentucky are about half as likely as Manhattanites to believe that climate change is happening. That's about as big a shock as discovering that Senators Mitch McConnell and Charles Schumer disagree on global warming. (McConnell, the majority leader, is from Kentucky, and Schumer, soon likely to become minority leader, is from New York.)
Still, there are some fascinating lessons in a paper describing the new statistical tool, published on Monday in Nature Climate Change.
Its authors say it makes reliable data on local perceptions about climate science and policy readily available for any sliver of the American landscape, at a level of detail that ordinary public-opinion polling can't replicate.
No matter how maddeningly often your own phone jangles during dinner, it turns out there aren't enough pollsters to precisely map the landscape of climate beliefs on an intimately local scale. To get such a granular view of the whole nation, years of polling data had to be carefully massaged.
Rather than spending an inordinate amount of time and money to conduct comprehensive polls in every state, in each Congressional district, the authors used a technique that has spread through the social sciences only recently.
Called "multilevel regression and poststratification," the method uses information from a series of nationally representative online panels that examined participants' climate beliefs. It is blended with other data to strengthen the model's predictive powers. (For example, data on how many same-sex couples live in a neighborhood might not have much to do with climate, but it can predict the level of liberalism; and data about car-driving habits can give clues about environmental consciousness.)
They tested the model's predictions of local beliefs with actual polling in four states and two cities, and found them accurate within a few percentage points, just as ordinary polls would be.
"It's kind of like suddenly having a microscope," said Anthony Leiserowitz, director of the Yale project on Climate Change Communication, one of the authors. The tool is being made available online for anybody to use.
Social scientists, advocates, educators, planners and policy-makers all need this kind of understanding, the authors argue, to make budget and other policy decisions, or to build support for pollution controls.
"For example, estimates could be used to evaluate support for renewable energy initiatives, to understand transportation behaviors, to gauge levels of policy support and to identify discrepancies between public opinion and political decision-making," they wrote.
The study's authors say that with so many decisions about climate policy being made in states and cities, local attitudes are more important than broad-brush national landscapes.
Nationally, 63 percent of Americans agree that the climate is changing. A majority think so in every state—even in West Virginia (54 percent) and Wyoming (55 percent), both big coal producers. The highest percentage (75 percent) is in Hawaii. In the District of Columbia, 81 percent agree. (There are only 75 counties in the country where more than half the people don't think climate change is real.)
The swings are greater when you look at smaller circles on the map. And the biggest gap of all is over whether to confront the climate crisis by controlling emissions of carbon dioxide.
These wide differences may make it harder politically to adopt meaningful changes like joining a strong international climate treaty, taxing or capping emissions of carbon dioxide, or spending more on researching alternatives to fossil fuels.
The convergence of public opinion, fossil fuel dependence, and intractable senators is hard to miss when states like Wyoming, Kentucky, and Louisiana sit on one side of an ideological gulf and California, New York and Hawaii perch on the other.
"Geographic patterns in beliefs are often consistent with what one might expect from political patterns, with traditionally blue states such as California and New York, for example, showing relative high concern about climate change, and red states such as Wyoming and Oklahoma showing lower concern," the study said.
"However, summarizing perceptions at the state level obscures variability at finer scales. In Teton County, Wyoming, for example, we estimate that 64 percent of adults believe that global warming is happening, similar to the national average, despite an estimate for the state as a whole of 55 percent. Likewise, projected belief in global warming is relatively low in Lewis County, Washington, a blue state, whereas the level of belief in the state as a whole is higher (67 percent)."
The tool discloses some other interesting quirks in the data, especially when it comes to differences among ethnic groups.
Hispanic districts in southwestern Texas, for example, are out of kilter with the climate denial prevalent in the rest of the state, as are majority-black districts in central Alabama.
"Of all racial and ethnic groups in America, it is Latinos that are most concerned about climate change," Lieserowitz said.
Urban dwellers are more likely to believe in global warming than rural regions. In college and university towns (think Ann Arbor, Mich.) the scientific consensus on climate change is especially likely to be well understood.