On the Impact of COVID-19 Pandemic Lockdowns on Atmospheric Particulate Matter in the United States
DEVONNE FRIDAY,
Embry-Riddle Aeronautical University Abstract Number: 643
Working Group: Control and Mitigation Technology
AbstractThe world has been facing a pandemic caused by the COVID-19 virus since early 2020. Community mitigation strategies were implemented in attempts to lower the risk for virus transmission. One such strategy included the issuance of lockdowns requiring persons to stay at home, resulting in reduced mobility and vehicular usage throughout several states. The transportation industry contributes significantly to concentrations of fine particulate matter (PM2.5) into the atmosphere. The COVID-19 lockdowns thus serve as a natural case study, providing an opportunity to better understand the sources and formation of atmospheric PM2.5. The aim of this study is to characterize the impact of the lockdowns associated with the COVID-19 pandemic on PM2.5 concentrations throughout ten states across different regions in the U.S. In addition to the fact that these states were issued stay at home mandates, the states under investigation were chosen to capture diverse ambient, meteorological, and environmental conditions. Furthermore, every chosen state encompasses several monitoring sites, offering reliable historic air quality data. Hourly PM2.5 concentrations and meteorological data were acquired from the U.S. EPA at all sites present at each of the relevant states during 2015 - 2020. Precipitation data is used to eliminate the effect of rainfall on PM2.5 levels. The study period was divided into three periods namely the “Pre-lockdown”, “Lockdown”, and “Post-lockdown” periods based on stay-at-home mandates at each state. To characterize the effect of the pandemic, concentrations of PM2.5 monitored in 2020 are compared to their corresponding historic data provided at the same sites during the same period from 2015 to 2019. Statistical testing is conducted to determine the significance of the changes in the hourly average concentrations of PM2.5 in 2020 compared to their historic averages. This work has implications for regulations of PM2.5 as a criteria pollutant in the U.S.