@article {651650,
	title = {NOx Emission Reduction and Recovery during COVID-19 in East China},
	journal = {Atmosphere},
	volume = {11},
	year = {2020},
	pages = {433},
	abstract = {Since its first confirmed case at the end of 2019, COVID-19 has become a global pandemic in three months with more than 1.4 million confirmed cases worldwide, as of early April 2020. Quantifying the changes of pollutant emissions due to COVID-19 and associated governmental control measures is crucial to understand its impacts on economy, air pollution, and society. We used the WRF-GC model and the tropospheric NO2 column observations retrieved by the TROPOMI instrument to derive the top-down NOx emission change estimation between the three periods: P1 (January 1st to January 22nd, 2020), P2 (January 23rd, Wuhan lockdown, to February 9th, 2020), and P3 (February 10th, back-to-work day, to March 12th, 2020). We found that NOx emissions in East China averaged during P2 decreased by 50\% compared to those averaged during P1. The NOx emissions averaged during P3 increased by 26\% compared to those during P2. Most provinces in East China gradually regained some of their NOx emissions after February 10, the official back-to-work day, but NOx emissions in most provinces have not yet to return to their previous levels in early January. NOx emissions in Wuhan, the first epicenter of COVID-19, had no sign of emission recovering by March 12. A few provinces, such as Zhejiang and Shanxi, have recovered fast, with their averaged NOx emissions during P3 almost back to pre-lockdown levels.},
	url = {https://www.mdpi.com/2073-4433/11/4/433},
	author = {Zhang, Ruixiong and Zhang, Yuzhong and Haipeng Lin and Xu Feng and Tzung-May Fu and Wang, Yuhang}
}
