Impacts of the COVID-19 Pandemic on Ambient Concentrations and Sources of Black Carbon in the United States
Marco Eugene, SANCHITA PAUL, Md. Aynul Bari,
University at Albany, SUNY Abstract Number: 498
Working Group: Carbonaceous Aerosol
AbstractBlack carbon (BC) is a potent short-lived climate pollutant and an important component of particulate matter emitted from fossil fuel combustion (e.g., diesel engines) and biomass burning (e.g., wood stoves) and has linked to adverse health outcomes. Globally, investigations have shown significant reductions of primary air pollutants such as PM2.5 and NO2, while significant increases of ground-level O3 and secondary particulate matter, as well as almost no significant changes were evident for CO2. To date, no attempt has been made in the United States to understand the effects of COVID-19 pandemic on ambient concentrations of black carbon. The specific objective was to determine the extent to which concentrations and anthropogenic sources of black carbon have changed during the COVID-19 pandemic.
We used available black carbon data for 19 different characteristics sites in 9 U.S. states covering residential, urban city centers, rural and suburban areas. We examined changes in black carbon concentrations during 2020 in relation to 2019 using non-parametric analysis for three different time periods i.e., pre-lockdown, lockdown, and reopening phase. Preliminary results indicated significant decreases in black carbon concentrations during lockdown period in urban city centers (e.g., Washington D.C., New Haven, Fort Lauderdale), while significant increases were also observed in some suburban and rural residential sites (e.g., Saint Petersburg, FL and Smithfield, UT). We evaluated diurnal variation in black carbon and identify local source impacts for different time periods. To identify and quantify changes in both local and regional black carbon sources during the COVID-19 pandemic, positive matrix factorization (PMF) was also applied using black carbon and PM2.5 speciation data. Findings can benefit the general public and the scientific community to improve understanding of COVID-19 impacts on black carbon and motivate them to take actions to reduce their carbon footprint to protect our environment.