Newswise — Just how far apart are Republicans and Democrats when it comes to views on climate change?

Not nearly as far as most assume, according to new University of Colorado Boulder research that surveyed more than 2,000 adults.

“Despite what we often hear about the deep divisions between parties, we found that there is actually general agreement that climate change is real, that human activity causes climate change, and that we should do something about it,” said Leaf Van Boven, a psychology and neuroscience professor at CU Boulder and lead author of the study, published today in Perspectives on Psychological Science.

The researchers also found that people are more likely to support the same climate policy proposal when they think that their own political party supports it. And both Democrats and Republicans overestimate how much their peers oppose the ideas of the other party.

“We found that people routinely place party over policy and disagree for the sake of disagreeing,” Van Boven said.

For the project, Van Boven and colleagues at the University of California, Santa Barbara set out to explore the psychological reasons that – despite warnings about economic, social and humanitarian impacts of climate change – U.S. lawmakers have yet to enact a national policy.

Previous studies and conventional wisdom suggested this was primarily because most Republicans are skeptical of climate change. 

So the researchers conducted two studies in 2014 and 2016 with diverse national panels of over 2,000 U.S. adults, asking: Is climate change happening? Does it pose a risk to humans? Is human activity responsible? And can reducing greenhouse gas emissions reduce climate change?

Sixty-six percent of Republicans, 74 percent of Independents, and 90 percent of Democrats said they believed in human-caused climate change and the utility of reducing greenhouse gases.

“Just before the presidential election when most Republicans were voting for Trump, who characterized climate change as a ‘hoax,’ they nevertheless expressed a belief in climate change,” notes Van Boven.

Party over policy

As part of the 2014 study, the researchers showed participants one of two proposed policies. One was a cap-and-trade policy which have historically been championed by Democrats. The other was a revenue-neutral carbon tax based on policies recently championed by Republicans.

Participants were told that 95 percent of Republicans and 10 percent of Democrats supported the policy, or vice versa.

Regardless of the content, Democrats supported policies from Democrats more often, and Republicans supported policies from Republicans more often.

In a related study of 500 people, also co-authored by Van Boven and published in Social Psychological and Personality Science, the authors used actual language from a proposed climate change policy that was part of ballot initiative I-732 in Washington State in 2016.

The researchers highlighted either Democrats or Republicans who genuinely supported or opposed the policy to the study volunteers and found similar results.

“Democratic and Republican citizens alike evaluate proposed climate policies based on who proposed it – above and beyond their thoughts on the details of the policy, or whether it coheres with their beliefs,” said senior author David Sherman, a professor in the Department of Psychological and Brain Sciences at UCSB.

The researchers also interviewed four retired members of Congress: Mickey Edwards (R-Ok.) Robert Inglis (R-South Carolina), David Skaggs, (D-Colo.) and Tim Wirth (D-Colo).

All four reported that as climate change became closely associated with Democrats, Republican disagreement increased.

“If you were interested in supporting climate change, that meant you were interested in supporting Al Gore,” Wirth told the researchers.

This distrust of the other side, combined with a false assumption that the two parties sharply disagree has made it difficult for good, bipartisan ideas to gain traction, said Van Boven.

“It is extremely difficult, psychologically, to publicly support a policy we think our peers will disagree with,” he said.

With several bipartisan climate change proposals in the works and election season around the corner, Van Boven hopes the papers will prompt voters to take a hard look at how they make decisions.

“We are often unwittingly swayed by partisan considerations even when it is in contrast with the way we would like to behave,” he said.