The New York Times writes about public opinion polls that reveal a dramatic increase in the number of people who are skeptical of climate science. Public perceptions are important in climate and energy policy, because it is difficult to justify mitigation policies to people who doubt that humans are causing climate change.

There are several potential reasons why skepticism is increasing. First, climate scientists were the subject of a great deal of negative publicity in late 2009 and early 2010 when e-mail messages from climate scientists at the University of East Anglia were hacked and a handful of errors were found in the Fourth Assessment Report of the IPCC.

Second, many parts of the United States and Northern Europe experienced an unusual cold winter. Recent research by political scientists Patrick J. Egan (New York University) and Megan Mullin (Temple University) shows that at least in the United States, local weather significantly influences whether people believe global warming is occurring. All this is somewhat paradoxical given that last April was globally the warmest ever recorded by NASA.

Finally, poor economic performance may also be a factor. If people are very worried about unemployment and finances, climate change loses importance as a policy problem. If people are uncomfortable with simultaneously believing that global warming is real and saying that it is not an important problem (cognitive dissonance), then bad economic times may lead the brain to solve the problem by downplaying the evidence for global warming.

However, it is important to remember that survey research is notoriously sensitive to how questions are framed. In a USA Today article, Stanford polling expert Jon Krosnick tells about his research indicating that the exact wording of survey questions drives the relative importance of global warming.

Public opinion may shift rapidly if the economy improves and the summer turns out to be warm. But in the long run, it is important to develop institutions that facilitate science communication. It appears as though mainstream media has somehow failed to give an accurate picture of the status of climate science.