Global warming estimates, media expectations, and the asymmetry of scientific challenge

Mass media in the U.S. continue to suggest that scientific consensus estimates of global climate disruption, such as those from the Intergovernmental Panel on Climate Change (IPCC), are “exaggerated” and overly pessimistic. By contrast, work on the Asymmetry of Scientific Challenge (ASC) suggests that such consensus assessments are likely to understate climate disruptions. This paper offers an initial test of the competing expectations, making use of the tendency for science to be self-correcting, over time. Rather than relying in any way on the IPCC process, the paper draws evidence about emerging science from four newspapers that have been found in past work to be biased against reporting IPCC findings, consistently reporting instead that scientific findings are “in dispute.” The analysis considers two time periods — one during the time when the papers were found to be overstating challenges to then-prevailing scientific consensus, and the other focusing on 2008, after the IPCC and former Vice-President Gore shared the Nobel Prize for their work on climate disruption, and before opinion polls showed the U.S. public to be growing more skeptical toward climate science once again. During both periods, new scientific findings were more than twenty times as likely to support the ASC perspective than the usual framing of the issue in the U.S. mass media. The findings indicate that supposed challenges to the scientific consensus on global warming need to be subjected to greater scrutiny, as well as showing that, if reporters wish to discuss “both sides” of the climate issue, the scientifically legitimate “other side” is that, if anything, global climate disruption may prove to be significantly worse than has been suggested in scientific consensus estimates to date.