Citation

Wu J, Zhou Y, Gao Y, Fu JS, Johnson BA, Huang C, Kim YM, Liu Y. Environ. Health Perspect. 2014; 122(1): 10-16.

Affiliation

Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.

Copyright

(Copyright © 2014, National Institute of Environmental Health Sciences)

DOI

10.1289/ehp.1306670

PMID

24192064

Abstract

BACKGROUND: It is anticipated that climate change will influence heat-related mortality in the future. However, estimates of excess mortality attributable to future heat waves are subject to large uncertainties, and have not been projected under the latest greenhouse gas emission scenarios. OBJECTIVES: We estimated future heat wave mortality in the eastern United States (~ 1,700 counties) under two Representative Concentration Pathways (RCPs), and investigated sources of uncertainty. METHODS: Using dynamically downscaled hourly temperature projections in 2057-2059, we projected heat wave days defined using four heat wave metrics, and estimated the excess mortality attributable to them. The sources of uncertainty in excess mortality estimates were apportioned using a variance-decomposition method. RESULTS: Estimates suggest that excess mortality attributable to heat waves in the eastern U.S. would result in 200-7,807 deaths per year (mean 2,379 deaths/year) in 2057-2059. Average excess mortality projections under RCP 4.5 and 8.5 scenarios were 1,403 and 3,556 deaths/year, respectively. Excess mortality would be relatively high in the southern states and eastern coastal areas (excluding Maine). The major sources of uncertainty were the relative risk estimates for mortality on heat wave versus non-heat wave days, the RCP scenarios, and the heat wave definitions. CONCLUSIONS: Estimates suggest that mortality risks from future heat waves may be an order of magnitude higher than in 2002-2004, with thousands of heat wave related deaths per year in the study area projected under the RCP 8.5 scenario. Substantial spatial variability in county-level heat mortality estimates suggests that effective mitigation and adaptation measures should be developed based on spatially resolved data.

Language: en