The Role of Forecast Confidence Intervals in Perception of Climate Change Risk

Climate scientists overwhelmingly agree that the global climate is changing and that human activities might be a critical driving factor. If their forecasts are correct, global climate change poses a serious risk to humanity. However, public response is decidedly not commensurate with the severity of the potential consequences of climate change. This is deeply problematic because failure to take precautionary action now could have devastating consequences in the future. The present psychological research explores how people interpret climate change forecasts and assess climate change risk. Participants completed a questionnaire with long-range forecasts for average temperature and sea level and were asked to give their own range of estimates of future outcomes, plus ratings of trust in and concern about the forecasts. Forecast time (four future time points) and place (local versus global forecasts) were experimentally manipulated between participants, as was the inclusion of confidence intervals: some participants received forecasts with predictive intervals, whereas other participants received only deterministic forecasts. Results are discussed in terms of the effects on climate change risk perception of time discounting, the personal relevance of forecasts, and trust in climate scientists. This research carries implications about the perception of climate change and how best to communicate climate change risk.