Abstract

A key component for public health adaptation strategies for local communities and governments is the development of methods for climate change population vulnerability screening. There have been few attempts to combine multiple climate change threats in a measure which addresses a more holistic concept of population vulnerability that includes exposure, population sensitivity, and adaptive capacity. We propose a screening method to identify populations at high risk from climate change impacts using population vulnerability and the effects of cumulative stressors. We also investigate if racial/ethnic and income disparities interact with climate change vulnerability. We chose several metrics based on the literature and data availability at the sub-county (census tract) level for two California counties. They included measures of exposure related to climate change (sea-level rise, flood risk, and wildfire risk); measures of population sensitivity (elderly living alone and car ownership); and measures of adaptive capacity (tree canopy, impervious surfaces, air conditioner use, and public transit access). We add a previously developed index (Environmental Justice Screening Method) which reflects measures of cumulative impacts. Validation was conducted by using emergency room data from a recent extreme weather event. Analysis of the final scores showed the highest vulnerability in the urban areas, except also at the coast in Los Angeles County. African-Americans and Latinos were more likely to reside in the top two vulnerability areas in both counties compared to whites, and median household income was inversely linearly related to vulnerability risk score. We present a simple and transparent screening tool which could be developed in other regions and could be modified in order to best assess the risks that are of the greatest concern in communities.