Climate Change, Humidity, and Mortality in the United States

Alan Barreca, Tulane University

This paper estimates the effects of temperature and humidity on mortality rates in the United States (c. 1968-2002) in order to provide insight into the potential health impacts of climate change. I find that humidity, like temperature, is an important determinant of mortality. Coupled with Hadley CM3 climate-change predictions, my estimates imply that mortality rates are likely to increase by about 1.3 percent by the end of the 21st century (c. 2070-2099). Although small on the aggregate, the bias from omitting humidity has significant implications for evaluating the distributional impacts of climate change on health.