The Authors, some Abrupt decline in tropospheric nitrogen dioxide over rights reserved; exclusive licensee China after the outbreak of COVID-19 American Association for the Advancement of Science. No claim to

Liu, F., A. Page, S.A. Strode, Y. Yoshida, S. Choi, B. Zheng, O.U.S. Government, P. Veefkind, P. Levelt, O.P. Hauser, J. Joiner, and U.A. Creative (2020), The Authors, some Abrupt decline in tropospheric nitrogen dioxide over rights reserved; exclusive licensee China after the outbreak of COVID-19 American Association for the Advancement of Science. No claim to, Liu et al., Sci. Adv., 6, eabc2992.
Abstract

China’s policy interventions to reduce the spread of the coronavirus disease 2019 have environmental and economic NonCommercial impacts. Tropospheric nitrogen dioxide indicates economic activities, as nitrogen dioxide is primarily emitted License 4.0 (CC BY-NC). from fossil fuel consumption. Satellite measurements show a 48% drop in tropospheric nitrogen dioxide vertical column densities from the 20 days averaged before the 2020 Lunar New Year to the 20 days averaged after. This decline is 21 ± 5% larger than that from 2015 to 2019. We relate this reduction to two of the government’s actions: the announcement of the first report in each province and the date of a province’s lockdown. Both actions are associated with nearly the same magnitude of reductions. Our analysis offers insights into the unintended environmental and economic consequences through reduced economic activities.