Scientists who study the climate system or the impacts of climate change on other environmental or social systems are often surprised at the level of public skepticism about the human role in climate change (anthropogenic climate change in the jargon of science). Scientists are particularly puzzled by the aggressive rejection of climate science by a segment of the U.S. population that has come to be known as climate change deniers.
Some people equate the phenomenon of climate change denial to the fierce rejection for decades to the scientific consensus that tobacco use contributed significantly to lung cancer, heart disease, and other health problems. In their book Merchants of Doubt, Oreskes and Conway suggest that some of the very same interests who questioned tobacco’s role in causing disease are also behind the climate science denial movement.
Americans have long held scientists in high esteem and are grateful for their contributions. The Pew Research Center finds that “79% of adults say that science has made life easier for most people and a majority is positive about science’s impact on the quality of health care, food and the environment.” But one area where there is a huge divergence between the population and the scientific community is on climate change. There is broad consensus in the scientific community that climate change is happening and that humans play a significant role in causing that change. Yet many Americans remain skeptical or in denial about the human role in climate change, as we can see in these Gallup survey data:
For social scientists the obvious question is: if Americans generally trust science, why do they deny the consensus among scientists about global climate change? There are several potential answers to this question, but two relate to the underlying psychology of the climate change problem.
First, climate science is addressing a problem rather than an opportunity for technological advancement. The complexity of the global climate is like that of the human body. But biomedical science offers hope that we can fix health issues using science that leads to new technologies. Climate science is identifying problems for which there are no easy technological solutions.
Second and even more to the point, climate science identifies problems for which the potential solutions threaten core values that many Americans hold. This is called the solutions aversion problem of climate change policy. The idea, developed by psychologists Campbell and Kay, is that when the obvious solutions to a problem violate a person’s core values (what I might call their world view) a natural response is to disbelieve that there is a problem. Climate change caused by humans clearly requires collective restraints on individual behaviors (we all need to produce fewer greenhouse gases). So, if you fundamentally object to any collective actions and believe the individual and free markets are paramount, you deny that the problem exists. Your aversion to climate change solutions leads you to deny the problem.
Why do I believe that humans are a primary cause of climate change? Because I have a basic understanding of how science works and I broadly trust the process. Just as biomedical science yields improving understanding of the complexities of the human body, so too does climate science lead us to a greater understanding of the global systems our lives depend on. Trusting climate science is the same self-interested behavior as trusting biomedical science.
Neither biomedical or climate science has led us to a perfect understanding of what is being studied. The human body and the global climate are too complex to get everything exactly right. But our understanding continues to grow.
Climate scientists use knowledge developed in the past to develop hypotheses. For example, we know that certain chemicals in the atmosphere tend to hold heat close to the planet for longer than that heat would be there without those chemicals. These chemicals are the so-called greenhouse gases, including carbon dioxide and methane. The hypothesis is that if there are more of these chemicals in the atmosphere more heat will be kept in for longer, like throwing another blanket on the bed on a Maine January night. More heat would then cause other changes in the climate system like increased rainfall. Now we have a simple hypothesis to test and climate scientists have been doing this type of hypothesis testing for decades.
But testing is not the end of the story. Scientists need to convince other smart scientists that they did their work correctly and that they drew the right conclusions from their research. We call this peer review. Scientists carefully examine each other’s work before it can be “published” in scientific journals. Reviews are usually rigorous and much more challenging than the comments one gets to blogs posted in the Bangor Daily News. (Comments also tend to be more civil than those posted in newspapers.) Research results only see the light of day if other scientists approve of it. I can attest — the process is no cake walk.
The system is not perfect, and sometimes research that is mistaken is published. And more often than not, the poor research that gets through the system is generally repudiated. When it comes to climate change, the science that survives this peer review supports the fact that humans have a significant role to play in causing the problem. Scientists who publish more are more likely to believe that humans are causing climate change. Other Gallup data show this:
We need to pay attention to what scientists are telling us before it is too late. Let’s not be like those who rejected the science on tobacco use because they were averse to the solution, the need to give up smoking. The stakes here are just as high.