The Climate Corner: Climate Change’s Unseen Consensus

By Anthony Leiserowitz, Ph.D., School of Forestry & Environmental Studies, Yale University

In the history of science, there have been few instances in which almost all experts in a particular field were in complete agreement. Climate change is one of those instances. Nearly two decades of research has converged on the following fact: More than 97 percent of climate scientists have independently concluded that human-caused global warming is happening.

In a new study published in Science magazine, Eric Plutzer and colleagues report a finding that should alarm the nation: Only 30 percent of middle-school and 45 percent of high-school science teachers in the U.S. are aware of the fact that nearly all climate scientists are convinced that global warming is caused mostly by human activities.

Here’s the kicker: The authors explain that although many science teachers themselves believe that climate change is happening, because most are not aware of the scientific consensus on human-caused climate change many opt to teach “both sides” of the so-called climate debate, mistakenly giving students the impression that the basic facts are still contested, rather than conveying the fact that there is a deep and well-established consensus among climate scientists.

A great deal of our own research, as well as that of many other researchers, has identified the importance of communicating the scientific consensus on human-caused climate change.

In particular, we find that people’s perception of the degree of scientific consensus acts as an important “gateway belief.” Many people’s thoughts and feelings about climate change – for example, that climate change is happening, human-caused and a serious threat that requires better climate policy – are influenced by their understanding of the scientific consensus.

To put it simply, educating – or failing to educate – people about the scientific consensus on human-caused climate change has important consequences for building public will to limit global warming, as America and 195 other nations pledged to do last December.

In their new study, Plutzer and colleagues report another important finding: Political ideology plays an important role in how teachers present the evidence on climate change. Importantly, our research has shown that one of the few facts that speaks to both conservatives and liberals in a powerful way is information about the scientific consensus on human-caused climate change.

In our experiments, we repeatedly find that conservatives are especially receptive to information about the consensus. In our latest national study (involving more than 6,000 Americans), we actually found that communicating the scientific consensus directly strengthens other important key beliefs that people hold about climate change, among conservatives, moderates and liberals alike.

This is not only true for climate science – perceived expert consensus also plays an important role in shaping public attitudes toward other scientific issues, such as vaccine safety. For example, conveying the high level of medical consensus on vaccine safety helps to correct influential misperceptions, such as public belief in fraudulent reports of a link between vaccines and autism.

There is something unique and important about the notion of expert consensus that sets it apart from other type of facts. For one, experts are a nonpartisan group, they come from all walks of life – conservative, moderate, liberal – and their message is simply scientific, not political. In fact, scientific consensus describes the level of agreement among the set of experts who are in the best position to know the science.

Second, group consensus is something we can all intuitively understand, and we use consensus as a heuristic to inform our decision-making because we know from experience that relying on expert consensus often leads to positive outcomes. For example, if nine out of 10 doctors told you that you need urgent medical treatment, your beliefs about what to do are likely guided by your perception of the consensus (and for good reason!).

At present, only about one out of 10 Americans understand the level of scientific consensus on human-caused climate change. Harvard science historian Naomi Oreskes points out that vested interest groups have spent millions of dollars on orchestrating disinformation campaigns with the explicit aim of undermining public understanding of the scientific consensus. Before climate change, the same happened in the debate over the link between smoking and lung cancer. Tobacco companies have long understood the psychological consequences of sowing doubt: As long as people think there is disagreement among the experts, most won’t act.

American children are currently being presented with a false debate. This needs to end: We urge secondary school science teachers to set the record straight by educating their students about the overwhelming degree of scientific consensus on human-caused climate change. Teaching this simple fact will help groom the next generation of American leaders to make decisions based on sound science – decisions that are in the best interest of the United States, other nations and our entire planet, including the crucial life support systems on which we all depend.

Anthony Leiserowitz, Ph.D., is the Director of the Yale Program on Climate Change Communication. The Yale Program on Climate Change Communications conducts scientific studies on public opinion and behavior; informs the decision-making of governments, media, companies, and advocates; educates the public about climate change; and helps build public and political will for climate action.

The Climate Corner is a monthly column featuring a variety of writers from around the state and Door County addressing various aspects of the challenges and opportunities climate change presents. The Corner is sponsored by the Climate Change Coalition of Door County, which is dedicated to “helping to keep our planet a cool place to live.” The Coalition is always open to new members and ideas. Contact the Coalition at [email protected].

Save the Date

The third annual Door County Climate Change Forum will be held at the Stone Harbor Resort in Sturgeon Bay on Saturday, May 7, 9 am to 2:30 pm.

Speakers include:

• Jonathan Patz, director of the UW Global Health Institute and lead author of the health-related chapters of the reports of the Nobel prize-winning Intergovernmental Panel on Climate Change.
• Rolf Nordstrom, CEO of the Great Plains Institute and co-author of the Midwest Chapter of the third National Climate Assessment.
• Kevin Shafer, executive director of the Milwaukee Metropolitan Sewerage District, a nationally recognized leader in the development of green infrastructure.
• Moderator: Tia Nelson, Wisconsin environmental leader.