Global Temperature and Global Mortality

This paper documents large indirect mortality impacts of climate change. Exploiting natural global temperature variability, we find that 1°C of warming increases annual mortality by 2.5 deaths per 1,000 individuals, compared to 0.1 deaths per 1,000 due to the associated local heat exposure. Using external estimates of the impact of global income on mortality, we show that the macroeconomic effects of global temperature changes explain two thirds of the gap between these estimates. We use this evidence to estimate damage functions in a neoclassical growth model that links mortality and economic activity and accounts for adaptation to mortality impacts. Mortality contributes $400 per ton of CO₂ to the Social Cost of Carbon, or one quarter of total climate damages. These results suggest that economic adaptation has a double dividend by also reducing climate-related mortality.