气候变化领域集成服务门户(CCPortal): Unraveling pathways of elevated ozone induced by the 2020 lockdown in Europe by an observationally constrained regional model using TROPOMI

CCPortal

DOI	10.5194/acp-21-18227-2021
	Unraveling pathways of elevated ozone induced by the 2020 lockdown in Europe by an observationally constrained regional model using TROPOMI
	Souri A.H.; Chance K.; Bak J.; Nowlan C.R.; González Abad G.; Jung Y.; Wong D.C.; Mao J.; Liu X.
发表日期	2021
ISSN	1680-7316
起始页码	18227
结束页码	18245
卷号	21 期号:24
英文摘要	Questions about how emissions are changing during the COVID-19 lockdown periods cannot be answered by observations of atmospheric trace gas concentrations alone, in part due to simultaneous changes in atmospheric transport, emissions, dynamics, photochemistry, and chemical feedback. A chemical transport model simulation benefiting from a multi-species inversion framework using well-characterized observations should differentiate those influences enabling to closely examine changes in emissions. Accordingly, we jointly constrain NOx and VOC emissions using well-characterized TROPOspheric Monitoring Instrument (TROPOMI) HCHO and NO2 columns during the months of March, April, and May 2020 (lockdown) and 2019 (baseline). We observe a noticeable decline in the magnitude of NOx emissions in March 2020 (14g%-31g%) in several major cities including Paris, London, Madrid, and Milan, expanding further to Rome, Brussels, Frankfurt, Warsaw, Belgrade, Kyiv, and Moscow (34g%-51g%) in April. However, NOx emissions remain at somewhat similar values or even higher in some portions of the UK, Poland, and Moscow in March 2020 compared to the baseline, possibly due to the timeline of restrictions. Comparisons against surface monitoring stations indicate that the constrained model underrepresents the reduction in surface NO2. This underrepresentation correlates with the TROPOMI frequency impacted by cloudiness. During the month of April, when ample TROPOMI samples are present, the surface NO2 reductions occurring in polluted areas are described fairly well by the model (model: -21g±g17g%, observation: -29g±g21g%). The observational constraint on VOC emissions is found to be generally weak except for lower latitudes. Results support an increase in surface ozone during the lockdown. In April, the constrained model features a reasonable agreement with maximum daily 8gh average (MDA8) ozone changes observed at the surface (rCombining double low line0.43), specifically over central Europe where ozone enhancements prevail (model: +3.73g±g3.94g%, +1.79gppbv, observation: +7.35g±g11.27g%, +3.76gppbv). The model suggests that physical processes (dry deposition, advection, and diffusion) decrease MDA8 surface ozone in the same month on average by -4.83gppbv, while ozone production rates dampened by largely negative JNO2[NO2]-kNO+O3[NO][O3] become less negative, leading ozone to increase by +5.89gppbv. Experiments involving fixed anthropogenic emissions suggest that meteorology contributes to 42g% enhancement in MDA8 surface ozone over the same region with the remaining part (58g%) coming from changes in anthropogenic emissions. Results illustrate the capability of satellite data of major ozone precursors to help atmospheric models capture ozone changes induced by abrupt emission anomalies. © 2021 Amir H. Souri et al.
语种	英语
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/246366
作者单位	Atomic and Molecular Physics (AMP) Division, Harvard-Smithsonian Center for Astrophysics, Cambridge, MA, United States; Institute of Environmental Studies, Pusan National University, Busan, South Korea; Us Environmental Protection Agency, Center for Environmental Measurement and Modeling, Research Triangle Park, NC, United States; Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, United States; Department of Chemistry and Biochemistry, University of Alaska Fairbanks, Fairbanks, AK, United States
推荐引用方式 GB/T 7714	Souri A.H.,Chance K.,Bak J.,et al. Unraveling pathways of elevated ozone induced by the 2020 lockdown in Europe by an observationally constrained regional model using TROPOMI[J],2021,21(24).
APA	Souri A.H..,Chance K..,Bak J..,Nowlan C.R..,González Abad G..,...&Liu X..(2021).Unraveling pathways of elevated ozone induced by the 2020 lockdown in Europe by an observationally constrained regional model using TROPOMI.ATMOSPHERIC CHEMISTRY AND PHYSICS,21(24).
MLA	Souri A.H.,et al."Unraveling pathways of elevated ozone induced by the 2020 lockdown in Europe by an observationally constrained regional model using TROPOMI".ATMOSPHERIC CHEMISTRY AND PHYSICS 21.24(2021).