Community clusters of tsunami vulnerability in the US Pacific Northwest

Proceedings of the National Academy of Sciences
Seth Spielman, University of Colorado, Boulder; Mathew C. Schmidtlein, California State University, Sacramento
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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.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Community clusters of tsunami vulnerability in the US Pacific Northwest
Series title Proceedings of the National Academy of Sciences
DOI 10.1073/pnas.1420309112
Volume 112
Issue 17
Year Published 2015
Language English
Publisher National Academy of Sciences
Publisher location Washington, D.C.
Contributing office(s) Western Geographic Science Center
Description 6 p.
First page 5354
Last page 5359
Country United States
State California, Oregon, Washington
Online Only (Y/N) N
Additional Online Files (Y/N) N
Google Analytic Metrics Metrics page
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