Migration, Climate Similarity, and the Consequences of Climate Mismatch.

This paper studies “climate matching” in migration—the idea that migrants choose destinations with climates similar to those of their origins—and examines how climate similarity shapes the spatial distribution of economic activity in the United States. The authors show that temperature distance between origin and destination predicts where migrants settle across U.S. counties, for both internal and international migrants, in both historical (1850–1940) and modern (1970–2019) periods. These patterns are not driven by spatial climate correlation or persistent ethnic networks, but instead by two channels: the transferability of climate-specific skills and the role of climate as a consumption amenity. Focusing on 1880–1920, a period of rapid growth and structural transformation, they use an IV strategy that interacts origin-country inflow shocks with the timing of railroad access across counties. They find that climate mismatch lowers agricultural productivity and speeds exit from farming, reduces manufacturing productivity, and slows population growth in mismatched counties. The long-run effects are sizable: a 1°C increase in climate mismatch between 1880 and 1920 is associated with roughly 2.5% lower per capita income in 1940.