In the United States, climate change is a highly polarizing topic. How can we reduce this political polarization? In our research on attitudes about climate change, we seem to have discovered an answer. When people are reminded that almost all climate scientists believe in climate change, they become much less skeptical about it. 

It is well-known that people put great faith in social consensus – and for good reason. Trusting social consensus is like getting a second opinion. But when consensus on an issue is high enough, this is more like getting a few thousand second opinions. As an obvious example, people once believed the earth is flat. But now that no reputable scientist believes this, people who believe that the earth is flat are extremely rare. In fact, according to a 2018 poll by YouGov, only about 2% of Americans think the earth is flat as a pancake.  

The Gateway Belief Model
All beliefs exist in a vast network of other beliefs. Your belief that stealing is wrong, for example, is probably connected to your belief that criminals should be jailed. Likewise, the belief that most scientists agree on an issue is strongly connected to an intricate web of other key beliefs.

Our Gateway Belief Model reflects this idea. It suggests that correcting the false belief that there is little scientific consensus on climate change leads to changes in many of people’s personal beliefs about climate change.  This includes the belief that climate change is happening, that it is caused by human activity, and that it is cause for worry. Changes toward such beliefs and feelings, in turn, are associated with greater support for public action to reduce climate change.

Political strategists have long understood the basic idea behind the Gateway Belief Model. For example, public opinion expert, Frank Luntz once argued the following: “should the public come to believe that the scientific issues are settled, their views about global warming will change accordingly. Therefore, you need to continue to make the lack of scientific certainty a primary issue in the debate.” Unfortunately, many Americans remain misinformed about the scientific consensus. For example, recent surveys show that only about 20% of Americans correctly understand that almost all climate scientists are convinced that global warming is happening and is human-caused.

Research in social psychology has shown that when people fail to recognize the opinions of others, uncovering these opinions can dramatically change people’s own attitudes and behavior. Our Gateway Belief Model is grounded in this idea.  In one recent study, we sampled 6,000 representative American adults.  We correctly informed half of these participants that “97% of climate scientists have concluded that human-caused global warming is happening.” The rest of the participants received no such information.

Those participants who got consensus information that virtually all climate scientists believe in global warming updated their own beliefs about the issue. Further, when they did so, this led to smaller but significant changes in their private attitudes about global warming, which in turn, were associated with greater support for public and Congressional action to make reducing global warming a priority. 

In another study, we surveyed Americans about both their own beliefs in human-caused climate change and their perceptions of the scientific consensus on climate change at two time points (7 months apart). Tracking changes in people’s beliefs allowed us to get a better handle on which beliefs were causing which other beliefs. Our results suggested that perceptions of scientific consensus at time 1 drive increased beliefs in global warming seven months later. Our results further suggested that believing that global warming is caused by human activity further reinforced later beliefs in the scientific consensus.

Consensus neutralizes conflict: Bridging the partisan divide
In study after study, we also found that these patterns of belief change are very similar for liberals and conservatives. This is especially true for highly educated liberals and conservatives. For example, in one recent study we found that both highly educated conservatives and highly educated liberals were very willing to change their perceptions of the scientific consensus about climate change.  These changes in beliefs were powerful enough to neutralize partisan conflict on the issue.

Why didn’t conservatives stick to their guns on this issue?  Our best guess is that, because people put so much stock in very high levels of agreement, perceptions of consensus can act as a powerful “foot-in-the-door”—or gateway—to changing related beliefs. Once people perceive that consensus for a belief reaches a critical mass, it may be very hard for them to ignore the consensus. 

Of course, people must place some amount of trust in the people whose consensus they evaluate. This is presumably why especially highly educated conservatives and liberals changed their views of climate change in response to information about the consensus.  Most educated people have faith in the integrity of science.  Although this raises questions about how to change the beliefs of devoted skeptics who devalue science, the percentage of Americans who understand the scientific consensus and believe that climate change is real and human-caused has been on the rise in recent years.

A critical first step to solve any group conflict is finding common ground. Although our approach does not offer a panacea, a shared understanding that experts have reached consensus about the problem can provide a stepping stone toward building bipartisan consensus on how to solve it.

Sander van der Linden is an Assistant Professor of Social Psychology in the Department of Psychology at the University of Cambridge, where he directs the Cambridge Social Decision-Making Lab.

Edward Maibach is Distinguished University Professor in the Department of Communication at George Mason University, where he directs the George Mason Center for Climate Change Communication.

Anthony Leiserowitz is a Senior Research Scientist and Director of the Yale Program on Climate Change Communication at Yale University.

For Further Reading
van der Linden, S., Leiserowitz, A., & Maibach, E. (2019). The Gateway Belief Model: A Large-Scale Replication. Journal of Environmental Psychology, 62, 49-58.

van der Linden, S., Leiserowitz, A., & Maibach, E. (2018). Perceptions of scientific consensus predict later beliefs about the reality of climate change using cross-lagged panel analysis. Journal of Environmental Psychology, 60, 110-111.

van der Linden, S., Leiserowitz, A., & Maibach, E. (2018). Scientific agreement can neutralize the politicization of facts. Nature Human Behaviour 2, 2-3.

Goldberg, M., van der Linden, S., Ballew, M., Rosenthal, S., & Leiserowitz, A. (2019). The role of anchoring in judgments about expert consensus. Journal of Applied Social Psychology 49(3), 192-200.