Carbon Monoxide Emissions from the Washington, DC, and Baltimore Metropolitan Area: Recent Trend and COVID-19 Anomaly

• DOI: 10.1021/acs.est.1c06288
• Publication Date: 2022-01-26T21:01:41Z
• Authors: Israel Lopez-Coto; Xinrong Ren; Anna Karion; Kathryn McKain; Colm Sweeney; Russell R. Dickerson; Brian C. McDonald; Doyeon Y. Ahn; Ross J. Salawitch; Hao He; Paul B. Shepson; James R. Whetstone
• Keywords: Air Pollutants; Carbon Monoxide; SARS-CoV-2; COVID-19; 01 natural sciences; 13. Climate action; Baltimore; District of Columbia; Humans; Pandemics; Environmental Monitoring; Vehicle Emissions; 0105 earth and related environmental sciences

We analyze airborne measurements of atmospheric CO concentration from 70 flights conducted over six years (2015–2020) using an inverse model to quantify the emissions Washington, DC, and Baltimore metropolitan areas. found that have been declining in area at a rate ≈−4.5 % a–1 since 2015 or ≈−3.1 2016. In addition, we show "Sunday" effect, with being lower, on average, than for rest week seasonal cycle is no larger 16 %. Our results also trend derived NEI agrees well observed trend, but daytime-adjusted are ≈50 our estimated emissions. 2020, collected during shutdown activity related COVID-19 pandemic indicate significant drop relative expected previous years, 23 mean 2016 February 2020. reduction April May. Last, this was driven mainly by traffic.