EXPERT OPINIONS IN THE MEDIA: ANALYSIS OF CLIMATE SCIENTISTS’ EVOLVING STANCES ON CLIMATE CHANGE (1980-2012)

The potential connection between Earth’s changing climate and recent increases in natural disasters has been gaining the media’s attention. To investigate one aspect of this trend, we analyzed quotes from climate scientists whom the media have frequently relied upon for their expert perspective. Our corpus consisted of U.S. newspaper and wireservice articles published between 1980 and 2012 that mentioned “drought” and “climate change” or “global warming.” We identified the 15 most cited scientists and tracked the evolution of their stances on climate change. Three of the scientists were staunch climate-change skeptics. Their positions trended away from complete denial of climate change toward acknowledging it, while continuing to argue that it may or may not be the result of human actions, and that it will not have adverse effects. In 2012, Patrick Michaels maintained, “Global warming is real and man-made pollutants may contribute to it, but it has a very small impact overall.” Concurrently, 12 of these frequently cited scientists became more confident that climate change is measurable, that humans contribute to the change, and that the change affects current extreme weather events. Most of these scientists appeared to possess a high degree of confidence by the mid-late 90’s, starting with James Hansen who stated in his 1988 testimony to Congress, ''Global warming has reached a level such that we can ascribe with a high degree of confidence a cause and effect relationship between the greenhouse effect and observed warming. It is already happening now.'' In 2012, Hansen further stated, “It is no longer enough to say that global warming will increase the likelihood of extreme weather … for the extreme hot weather of the recent past, there is virtually no explanation other than climate change.” Based on the trends in perspectives of these climate scientists, we predict the number of news articles discussing the impact of climate change on natural disasters will continue to increase. The trends also suggest that in the near future, even climate scientists who have been skeptics may acknowledge that climate change is at least partially responsible for the increasing number of natural disasters.