WASHINGTON -- Climate activists' strategy of barraging people with information about the consequences of climate change could end up hurting the cause, according to a benchmark study released Thursday.
The study, commissioned by the Stanford Woods Institute for the Environment and the Center for Ocean Solutions, is the first in-depth study of its kind to examine climate change adaptation and prevention efforts. The survey was conducted via the Internet with a nationally representative probability sample of roughly 1,200 adults. The margin of error is 4.9 percent at the 95 percent confidence level.
Survey questions were formulated to assess participants' beliefs about climate change and gather opinions about its impact on communities, the economy and jobs. Specifically, it measured concern about two areas of climate impact -- estimates of sea level rise and storm predictions -- and how to communicate scientific uncertainty.
Scientists believe that, in the next hundred years, global warming will cause the level of oceans around the world to rise about four feet on average, but there is some degree of uncertainty built into the modeling process. Sea level could rise by as much as seven feet -- what scientists refer to as the "high tail" of the probability curve -- or it could rise by as little as one foot, what they call the "low tail," according to the survey.
Full acknowledgement of uncertainty increased survey respondents' acceptance of climate change when discussing sea level rise in isolation.
"If scientists fully confess their uncertainty to the public, this appears to increase trust," said survey director Jon Krosnick, a senior fellow at the Stanford Woods Institute for the Environment and professor of communication, of his findings.
But when the disclosure regarding sea level is coupled with predictions of climate change's effects on storm intensity, however, that trust didn't hold.
When scientists told respondents about both the uncertainty on sea level rise and the potential for extreme weather, fewer survey respondents (51 percent) registered concern than when the storm information was presented alongside a simple high tail prediction of sea level rise (62 percent).
One reason for that, Krosnick suggested, could be that people are "overwhelmed" by information and "psycho defenses kick in."
To take a real-world example, consider the critique Jeff Masters, director of meteorology at the Weather Underground, gave to Al Gore's global warming movie, "An Inconvenient Truth," which sought to draw attention to the dangers posed by climate change. Masters wrote:
[Gore] shows animations of what a 20-foot rise in sea level would do to Manhattan, Florida, India, and China. A 20-foot sea level rise is what we expect if all of Greenland or all of the West Antarctic Ice Sheet were to melt. Such a 20-foot rise is not expected by 2100, and it would have been appropriate for Gore to acknowledge that the consensus of climate scientists--as published in the most recent report by the United Nations' Intergovernmental Panel on Climate Change (IPCC)--is that sea level is likely to rise between 4 and 35 inches, with a central value of 19 inches, by 2100.
Perhaps such transparency could do more than pacify Gore's critics, provided he doesn't overwhelm them with information. If this study is right, it could help him and other advocates gain greater public acceptance of the scientific reality of climate change.