Coastal Emergency Managers’ Risk Perception and Decision Making for the Tonga Distant Tsunami

Abstract

On January 15, 2022, the Hunga-Tonga-Hunga-Ha’apai (Tonga) volcano erupted and triggered a tsunami forecasted to reach North America. This event provided a unique opportunity to investigate risk perception and communication among coastal emergency managers and emergency program coordinators (EMs). In response, this research explores 1) how risk can be communicated most effectively and 2) how risk perceptions associated with ”distant” tsunami alerts and warnings affect EMs’ willingness to issue emergency alerts. A purposive sample of coastal EMs (n=21) in the U.S. Pacific Northwest participated in semi-structured interviews. Participants represented Tribal, county, state, and federal agencies in Washington, Oregon, and California. Interview transcripts were deductively coded and thematically analyzed. Participants perceived low risk from the Tonga tsunami but took precautionary measures and alerted the public. Participants described how their actions were driven by community characteristics and the anticipated reactions to messaging among residents. Many reported the need to balance notifying the public and avoiding the negative impacts of their messaging (e.g., “crying wolf,” panic, curiosity). The unique nature of the event led to identification of unanticipated facilitators and barriers to decision-making among participants. These findings can inform distant tsunami risk communication and preparedness for coastal communities.

Keywords: Tsunamis, risk assessment, Risk Communication, emergency management