Community clusters of tsunami vulnerability in the US Pacific Northwest

Nathan J. Wood; Jeanne M. Jones; Seth Spielman; Mathew C. Schmidtlein

doi:10.1073/pnas.1420309112

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Community clusters of tsunami vulnerability in the US Pacific Northwest

Nathan J. Wood·Jeanne M. Jones·Seth Spielman·Mathew C. Schmidtlein

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Abstract

Many coastal communities throughout the world are threatened by local (or near-field) tsunamis that could inundate low-lying areas in a matter of minutes after generation. Although the hazard and sustainability literature often frames vulnerability conceptually as a multidimensional issue involving exposure, sensitivity, and resilience to a hazard, assessments often focus on one element or do not recognize the hazard context. We introduce an analytical framework for describing variations in population vulnerability to tsunami hazards that integrates ( i ) geospatial approaches to identify the number and characteristics of people in hazard zones, ( ii ) anisotropic path distance models to estimate evacuation travel times to safety, and ( iii ) cluster analysis to classify communities with similar vulnerability. We demonstrate this approach by classifying 49 incorporated cities, 7 tribal reservations, and 17 counties from northern California to northern Washington that are directly threatened by tsunami waves associated with a Cascadia subduction zone earthquake. Results suggest three primary community groups: ( i ) relatively low numbers of exposed populations with varied demographic sensitivities, ( ii ) high numbers of exposed populations but sufficient time to evacuate before wave arrival, and ( iii ) moderate numbers of exposed populations but insufficient time to evacuate. Results can be used to enhance general hazard-awareness efforts with targeted interventions, such as education and outreach tailored to local demographics, evacuation training, and/or vertical evacuation refuges.

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Proceedings of the National Academy of Sciences Article

Source-reported bounding extent: 39.842286020743394° to 49.081062364320736° latitude; -124.73876953125° to -120.82763671875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Nathan J. Wood, Jeanne M. Jones, Seth Spielman, Mathew C. Schmidtlein. 2015-04-13. Community clusters of tsunami vulnerability in the US Pacific Northwest. https://doi.org/10.1073/pnas.1420309112

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