Extreme Weather Disasters, Economic Losses via Migration, and Widening Spatial Inequality in the U.S.

In 2017, the U.S. set a new record of $313 billion in economic losses from sixteen billion-dollar extreme weather disasters. Economic losses from extreme weather disasters are spatially concentrated in states like Florida and are remarkably stable over time. While there are many reasons that people stay in disaster-prone areas, others choose to migrate or are forced to leave, some temporarily and others permanently. As economic actors, migrants take with them myriad economic activities that constitute economic losses that have not been studied in previous research. This project will be the first to document the size of economic losses via migration from affected areas in the U.S. after extreme weather events. Because migration necessarily connects places to one another, the project will also document whether and to what extent such economic losses via migration contribute to changing spatial inequality in the U.S. as a whole. Project results will provide input into policies concerning how to mitigate the economic costs of extreme weather disasters in the U.S., thus contributing to disaster recovery and economic prosperity.

This project uses county-level data from the Statistics of Income program at the Internal Revenue Service (IRS) and the Federal Reserve Bank of New York Consumer Credit Panel (CCP) to document and analyze economic losses via migration from affected areas after extreme weather disasters in the U.S. over the past two decades. Total economic losses via migration are measured in the IRS and CCP data using information on aggregate adjusted gross income and debt-financed consumption activities, respectively. After summarizing the size of economic losses via migration from affected areas after extreme weather disasters, the project will use demographic decomposition procedures to distinguish the relative contributions of economic components (average, or per capita, economic losses via migration) and demographic components (the propensity to migrate, as well as population size in the affected area). Further acknowledging the inherently spatial character of migration, this project also documents whether and to what extent economic losses via migration from affected areas after extreme weather disasters contribute to changing spatial inequality in the U.S. using two variants of the Gini Index that measure spatial focusing among flows in migration networks. Given heterogeneity in the relationship between extreme weather disasters and migration, this project takes a case-specific and comparative approach, focusing on three types of extreme weather disasters, including tropical cyclones, tornadoes, and wildfires, in counties that have experienced the bulk of economic losses over the last twenty years according to the Spatial Hazards Events and Losses Database for the United States (SHELDUS).

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.