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Sahan Dissanayake and Grace Arnold

Journal of Economic Literature Classification Codes

I18, Q53, Q58


COVID-19 (Disease) -- Social aspects, COVID-19 (Disease) -- Environmental aspects


Using a difference-in-differences approach, I test whether the U.S. COVID-19 lockdowns influenced air pollution levels. I hypothesize that the halt in human mobility stemming from lockdowns caused transportation sector activity to decrease, leading to a reduction in related pollutants such as PM2.5, PM10, and NO2. I investigate whether counties with strict lockdown policies experienced greater improvements in air pollution relative to before the lockdowns than counties with lenient lockdown policies. I use lockdown stringency data from the University of Oxford to identify strict versus lenient counties, and data from the Environmental Protection Agency to capture air pollution outcomes. The main results provide insufficient evidence of differential air pollution levels between the strict and lenient groups. An examination of only metropolitan counties produces similar results, suggesting stricter lockdowns may not be associated with lower pollution levels, even in urban areas where transportation sector activity is typically elevated.


© 2021 Ashlyn B. Cenicola

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This work is licensed under a Creative Commons Attribution 4.0 License.



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