Emotional responses and perceptions of false alarms in flood warnings and their impact on evacuation action: an empirical analysis of the Kyushu Region, Japan

This study examines perceptions, emotions and actions regarding false flood warnings among residents of Japan’s Kyushu Region, with the aim of improving socially effective flood early warning systems. Using municipality-level false alarm ratio (FAR) data and survey responses from 997 residents, the study investigates how people define warning “hits”, how they respond emotionally to false alarms, and how actual and perceived false alarm ratios influence evacuation behaviour. The findings show that most respondents considered a warning to be a hit when river water reached a hazardous level or when an overflow or levee breach occurred. False alarms were associated with decreased negative emotions, including sadness and anger, and increased positive emotions, including feeling pleased and at ease.

This document finds no significant relationship between actual FAR and perceived FAR, regardless of how respondents defined a warning hit. However, perceived FAR had a significant negative effect on the probability of evacuation, suggesting that people who perceive warnings as frequently inaccurate are less likely to take protective action. The study also finds that this negative effect is weaker among individuals who experience positive emotions towards false alarms. The authors conclude that effective flood early warning systems require risk communication strategies that consider emotional responses to false alarms, promote trust in warning issuers and encourage people to view false alarms as opportunities for preparedness rather than failures.