Storms and Sorting: The Partisan Impact of Domestic Climate Migration

Abstract

As climate-induced natural disasters increase in frequency and severity, domestic climate migration is shifting from a future projection to a present reality in the United States. While the political impacts on “origin communities,” areas facing climate disasters from which people may move, are well-documented, the political consequences for communities receiving climate migrants remain minimally researched. This paper investigates how climate migrants influence the partisan alignment of the communities they are moving to, particularly the “receiving counties.” By integrating IRS county-to-county migration data, the FEMA National Risk Index, election results from the National Neighborhood Data Archive (NaNDA) between 2016 and 2020, and Census data, I test whether migration from climate-vulnerable areas predicts shifts in Democratic vote share.

Building on theories of ideological sorting, spatial dependence, and risk perception, I find that the proportion of movers from areas with moderate-to-high climate risk is a statistically significant predictor of increased Democratic vote share in receiving counties. This suggests that climate-induced mobility is not politically neutral. That it may involve Democratic-leaning individuals proactively seeking to move to areas that are safer from climate impacts, areas often vote for Democratic candidates. While climate migrants currently represent a small fraction of the electorate, these findings suggest that intensifying environmental displacement could fundamentally reshape the American political landscape as climate change intensifies.