Economic Impacts of Climate Change in the United States: Integrating and Harmonizing Evidence from Recent Studies

This paper synthesizes evidence on climate change impacts specific to U.S. populations. We develop an apples-to-apples comparison of econometric studies that empirically estimate the relationship between climate change and gross domestic product (GDP). We demonstrate that with harmonized probabilistic socioeconomic and climate inputs these papers project a narrower and lower range of 2100 GDP losses than what is reported across the published studies, yet the implied U.S.-specific social cost of greenhouse gases (SC-GHG) is still greater than the market-based damage estimates in current enumerative models. We then integrate evidence on nonmarket damages with the GDP impacts and recover a jointly-estimated SC-GHG. Our findings highlight the need for more research on both market and nonmarket climate impacts, including interaction and international spillover impacts. Further investigation of how results of macroeconomic and enumerative approaches can be integrated would enhance the usefulness of both strands of literature to climate policy analysis going forward.