id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-311827-jfdlb2g8	Chen, L.-W. Antony	Nonuniform impacts of COVID-19 lockdown on air quality over the United States	2020-07-21		.txt	text/plain	1544	96	60	Abstract Most of the state governments in United States (U.S.) issued lockdown or business restrictions amid the COVID-19 pandemic in March 2020, which created a unique opportunity to evaluate the air quality response to reduced economic activities. Data acquired from 28 long-term air quality stations across the U.S. revealed widespread but nonuniform reductions of nitrogen dioxide (NO2) and carbon monoxide (CO) during the first phase of lockdown (March 15–April 25, 2020) relative to a pre-lockdown reference period and historical baselines established in 2017–2019. The lockdown or stay-at-home orders issued by the U.S. government to counter the COVID-19 pandemic has nonuniformly impacted air pollution in the U.S. More consistent NO 2 and CO declines than other pollutants coincide with reduced transportation and utility demands, while inter-site differences reflect not only the local lockdown policy but also population density. Assessing air quality changes in large cities during COVID-19 lockdowns: The impacts of traffic-free urban conditions in Almaty	./cache/cord-311827-jfdlb2g8.txt	./txt/cord-311827-jfdlb2g8.txt