daf09a936076b46dac53bfa9ddd96669-origStrong scientific consensus will not generate public support for environmental policy, unless skeptical voices become almost silent.  Surveys have shown that perceptions of scientific dissent undermine public support for environmental policy[1]. Even a few vocal or organized scientific and media voices can cause a perception of uncertainty in the public, a tactic used by tobacco companies in the 50’s and 60’s to sway public opinion away from the dangers of smoking. A paper, since debunked as quackery, about vaccines and autism has led to 30% of the American public believing there is a connection according to PEW survey.[2] Likewise, organizations like the Heartland Institute[5] focus on manufacturing doubt about scientific consensus on climate change even though the scientific consensus on climate change approaches 97%. 

The idea of “cultural cognition” refers to the tendency of individuals to form risk perceptions that are congenial to their values.[3] Study participants had differing views on what the expert consensus was on issues of climate change, nuclear waster disposal, and the effect of concealed weapon permits based on whether the experts opinion agreed or disagreed with their values.

According to an article in Environmental Science & Policy, ‘Public support for environmental policy is maximized when the subjects receive no information about the scientific debate, indicating that the general public’s default assumption is a very high degree of scientific consensus. Accordingly, a stronger scientific consensus will not generate public support for environmental policy, unless skeptical voices become almost silent.’

A recent study supported by AAAS describes how even a small dissent in the scientific community can reflect uncertainty in the public mind. Almost 97% of experts agree that climate change is real and humans have contributed to it, but only one in ten Americans knows how much scientific consensus there is.[4] Most believe there is significant uncertainty in the scientific community and the PEW survey shows only half believe climate change is real.

A few ‘experts’ or vocal political action groups can cause widespread public opinion of scientific uncertainty where none exists. These ‘manufacturers of doubt’ dispute that scientific consensus exists and rely on cultural cognition of the public to give more credibility to expert opinions that agree with their values, no matter how few of those opinions exist.  Perceived scientific consensus is an important gateway belief that influences public policy and climate change deniers have had significant negative impact on the political will to address climate change.[6]


Joseph Bast, President of Heartland Institute

The media as a ‘manufacturer of doubt’ can have a negative impact on the belief by the public that there is a no scientific consensus when in fact there is one. A Wall Street Journal article “The Myth of Climate Change ‘97%'” challenges that there is a scientific consensus by manufacturing doubt with shady arguments. The opinion co-authored by Joseph Bast, President of the Heartland Institute[5], which is the “the primary American organization pushing climate change skepticism,” according to the New York Times.  They do not address whether climate change is real or not. Instead they focus on manufacturing doubt about scientific consensus.

For example in his article Bast states

“Surveys of meteorologists repeatedly find a majority oppose the alleged consensus. Only 39.5% of 1,854 American Meteorological Society members who responded to a survey in 2012 said man-made global warming is dangerous.”

Bast neglects to mention that 89% agreed that there was global warming and 88% thought it would cause harm. by focusing on a narrow definition of dangerous he is able to sow doubt in the belief that there is a consensus even though there is a very high consensus.  What is more is that these are not experts, survey participants were required to have only 20 semester hours of work in a related field.

By strategically sowing seeds of doubt, organized opponents of climate change action have tried to undermine the validity of the scientific consensus. Repeated exposure to simple messages that correctly state the actual scientific consensus on human-caused climate change is a strategy likely to help counter the concerted efforts to misinform the public.[4]