Responses to severe weather warnings and affective decision-making

When public agencies provide information provision to help people make better decisions, they often face the choice between economy and completeness. For weather services warning people of high-impact weather events, this choice is between offering standard warnings (SWs) only of the weather event itself, such as wind-speed, or also describing the likely impacts (so-called impact-based warnings, IBWs). Previous studies have shown IBWs to lead to a greater behavioral response. These studies, however, have relied on surveys describing hypothetical weather events; given that participants did not feel threatened, they may have been more likely to process the warning slowly and analytically, which could bias the results towards finding a greater response to the IBWs. In this study, we conducted a field experiment involving actual and potentially threatening weather events for which there was variance with respect to the time interval between the warning and the forecasted event and for which we randomly assigned participants to receive SWs or IBWs. We observe that shorter time intervals led to a greater behavioral response, suggesting that fear of an imminent threat is an important factor motivating behavior. We observe that IBWs did not lead to greater rates of behavioral change than SWs, suggesting that when fear is a driving factor, the additional information in IBWs may be of little importance. We note that our findings are highly contextualized, but we call into question the prevailing belief that IBWs are necessarily more helpful than SWs.