The double-edged sword of learning from disasters: Mortality in the Tohoku tsunami

Learning from natural disasters is predominantly regarded as beneficial: Individuals and governments learn to cope and thereby reduce damage and loss of life in future disasters. We argue against this standard narrative and point to two principal ways in which learning from past disasters can have detrimental consequences: First, investment in protective infrastructures may not only stimulate settlement in hazard-prone areas but also foster a false impression of security, which can prevent individuals from fleeing to safe places when hazard strikes. Second, if disaster events in the past did not have catastrophic consequences, affected individuals do not take future events sufficiently seriously. As a consequence, learning from disasters is a double-edged sword that can prevent large scale damage and human loss most of the time but results in the worst case scenario when a disaster occurs at an unexpected scale and public preparedness measures fail. We demonstrate the devastating impact of misplaced trust in public preparedness measures and misleading lessons drawn from past experience for the case of the 2011 Tohoku tsunami. Our paper contributes to the literatures on ‘negative learning’ and ‘hazard maladaptation’ by demonstrating that a lack of past experience with tsunami mortality in a municipality substantively increases mortality in the Tohoku tsunami.