Assessing Vulnerability to Natural Hazards: Impact-Based Method and Application to Drought in Washington State

This article presents a technique for performing vulnerability assessments, using measures of exposure, sensitivity, and adaptive capacity. Historically, vulnerability assessments have focused on analyzing the hazard itself, absent information on its causes and mitigations. The vulnerability assessment method (VAM), presented herein, acquires data and information from affected stakeholders to assess not only the hazard, but also the causes of vulnerability, potential for adaptation, previous impacts, and ways to mitigate future impacts. We apply the VAM to a case study of Washington State, assessing drought vulnerability across 34 subsectors. Results indicate highest vulnerability for dryland farmers, farmers with junior water rights, fisheries, ski area operators, berry farmers, and the green industry. Through validation exercises, we demonstrate the VAM's internal consistency and external applicability. Contributions of the VAM include its incorporation of stakeholder data, integrated and quantitative assessments of vulnerability components, and applicability to other regions, scales, and types of hazards.