By Naomi Oreskes and Erik M. Conway
In 1993, Willett Kempton, a prominent social scientist at the University of Delaware, posed the question, "Will public environmental concern lead to action on global warming?" At the time, it seemed that it would.
In 1988 we had experienced record heat in the United States: The U.S. National Climatic Data Center (NCDC) estimated direct losses from heat waves and drought at $40 billion (plus $30 in indirect losses) and 5,000 to 10,000 excess deaths--effects that received widespread publicity. In Congress, U.S. Sens. Timothy Wirth and Bennett Johnston introduced the National Energy Policy Act "to establish a national energy policy [to] reduce the generation of carbon dioxide and trace gases as quickly as is feasible in order to slow the pace and degree of atmospheric warming." While running for president, Vice President George H.W. Bush pledged to use the "White House effect" to combat the "greenhouse effect." And in 1992, the new U.S. president signed the U.N. Framework Convention on Climate Change, which pledged the United States, along with 164 other signatories, to prevent "dangerous anthropogenic interference" in the climate system.
Eighteen years later, we've done little to fulfill that promise, and globally, temperatures continue to rise.
Just this summer, the U.S. National Oceanic and Atmospheric Association (NOAA) released its latest summary of the state of the climate, which concludes that the last three decades have been "progressively warmer than all earlier decades." While the data for 2010 are not yet in, scorching temperatures around the globe -- including a record 102 degrees in Moscow -- has led NOAA to conclude that 2010 will be one of the hottest years on record. Meanwhile, the need to reduce our dependency on oil was made acutely clear as we watched helplessly oil gush from BP's damaged rig in the Gulf of Mexico.
So why are the American people not clamoring for action?
One reason is that a significant percentage of the American people -- about 24 percent, according to one recent study -- still doubt or dismiss the severity of the problem. On the basic question of whether climate change is a serious threat, it seems that we have gone backward. In 1989, in response to a survey asking if various problems were "serious," 79 percent of respondents said "yes" for the greenhouse effect, and when asked about the level of the threat, 69 percent said the greenhouse effect was a "clear threat." Another poll that same year found 60 percent "extremely" or "somewhat" worried.
Yet this year, a major study found only 41 percent of respondents describing themselves as "alarmed" or "concerned." Even as global temperatures have risen, concern about global warming has fallen.
Part of the explanation for this involves confusion or skepticism about the science. Scientifically, we know that just as a single hot summer does not prove global warming, neither does a single cold winter disprove it. Yet 51 percent of respondents recently said that the snowstorms in the eastern United States last winter made them question whether global warming was occurring. And 24 percent doubt or dismiss the scientific evidence entirely.
There is an explanation for this state of affairs, as we explain in our new book, "Merchants of Doubt: How a Handful of Scientists Obscured the Truth on Issues from Tobacco Smoke to Global Warming."
Climate change has been subject to a sustained effort to challenge the scientific evidence, and to use irrelevant anomalies as counter-evidence against the overall pattern. Beginning in the late 1980s -- just as the scientific evidence of global warming was beginning to gel -- conservative scientists and regulated industries joined hands with think tanks such as the George C. Marshall Institute, the Cato Institute, the American Enterprise Institute and the Heartland Institute to question that evidence.
If the American people and our leaders came to accept the severity of the threat, then we would accept the need for government intervention in the marketplace to control the use of fossil fuels--and maybe other things as well.
Climate change is a market failure -- a "negative externality" in economists' jargon -- a problem whose costs are not reflected by the market price of fossil fuels, and for which the free market has not, of its own accord, offered a solution. Free-market ideologues have resisted this conclusion for obvious reasons.
While there are many principled conservatives and libertarians, it is hard to avoid the conclusion these think tanks, which receive substantial funding from the fossil fuel and other regulated industries, follow no principle except self-interest. Emissions trading may or may not be the answer to global warming, but whatever happens, it will not be devastating to our economy and way of life.
On the other hand, if we do nothing to stop the rise of global temperatures, the melting of sea ice and the thawing of permafrost, then sea level will rise, coastal erosion will increase, heat waves will become more deadly, hurricanes will become stronger, insect pests will change their geographic distribution, and Glacier National Park will lose its glaciers.
If currents trends continue, Minnesota might soon feel and look more like Missouri. And that will affect our economy and our way of life.
Naomi Orekes is a historian of science at the University of California, San Diego. Erik M. Conway is a historian of science living in Pasadena, Calif.