气候变化领域集成服务门户(CCPortal): Nonlinear response of nitrate to NOx reduction in China during the COVID-19 pandemic

CCPortal

DOI	10.1016/j.atmosenv.2021.118715
	Nonlinear response of nitrate to NOx reduction in China during the COVID-19 pandemic
	Ren C.; Huang X.; Wang Z.; Sun P.; Chi X.; Ma Y.; Zhou D.; Huang J.; Xie Y.; Gao J.; Ding A.
发表日期	2021
ISSN	1352-2310
卷号	264
英文摘要	In recent years, nitrate plays an increasingly important role in haze pollution and strict emission control seems ineffective in reducing nitrate pollution in China. In this study, observations of gaseous and particulate pollutants during the COVID-19 lockdown, as well as numerical modelling were integrated to explore the underlying causes of the nonlinear response of nitrate mitigation to nitric oxides (NOx) reduction. We found that, due to less NOx titration effect and the transition of ozone (O3) formation regime caused by NOx emissions reduction, a significant increase of O3 (by ∼ 69%) was observed during the lockdown period, leading to higher atmospheric oxidizing capacity and facilitating the conversion from NOx to oxidation products like nitric acid (HNO3). It is proven by the fact that 26–61% reduction of NOx emissions only lowered surface HNO3 by 2–3% in Hebi and Nanjing, eastern China. In addition, ammonia concentration in Hebi and Nanjing increased by 10% and 40% during the lockdown, respectively. Model results suggested that the increasing ammonia can promote the gas-particle partition and thus enhance the nitrate formation by up to 20%. The enhanced atmospheric oxidizing capacity together with increasing ammonia availability jointly promotes the nitrate formation, thereby partly offsetting the drop of NOx. This work sheds more lights on the side effects of a sharp NOx reduction and highlights the importance of a coordinated control strategy. © 2021 The Author(s)
关键词	COVID-19 Emission reduction Enhanced NH3 Nitrate pollution Ozone
语种	英语
scopus关键词	Emission control; Nitrates; Nitric acid; Nitric oxide; Nitrogen oxides; Ozone; COVID-19; Emission reduction; Enhanced NH3; Haze pollutions; Nanjing; Nitrate pollution; Nitric oxide emissions; Nitric oxide reduction; Non-linear response; Oxidizing capacity; Ammonia; ammonia; fossil fuel; hydroxyl radical; nitrate; nitric acid; nitric oxide; ozone; sulfate; COVID-19; emission control; nitrate; nitric acid; nitric oxide; ozone; spatiotemporal analysis; air pollution; animal husbandry; Article; chemical composition; China; circadian rhythm; combustion; comparative study; coronavirus disease 2019; diffusivity; environmental temperature; fertilizer application; human; lockdown; oxidation; pandemic; particulate matter 2.5; photochemistry; production efficiency; quality control; reduction (chemistry); simulation; surface property; titrimetry; volatilization; China; Hebi; Henan; Nanjing [Jiangsu]
来源期刊	ATMOSPHERIC ENVIRONMENT
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/248222
作者单位	Joint International Research Laboratory of Atmospheric and Earth System Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing, 210023, China; Jiangsu Provincial Collaborative Innovation Center of Climate Change, Nanjing, 210023, China; Frontiers Science Center for Critical Earth Material Cycling, Nanjing University, Nanjing, 210023, China; Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
推荐引用方式 GB/T 7714	Ren C.,Huang X.,Wang Z.,et al. Nonlinear response of nitrate to NOx reduction in China during the COVID-19 pandemic[J],2021,264.
APA	Ren C..,Huang X..,Wang Z..,Sun P..,Chi X..,...&Ding A..(2021).Nonlinear response of nitrate to NOx reduction in China during the COVID-19 pandemic.ATMOSPHERIC ENVIRONMENT,264.
MLA	Ren C.,et al."Nonlinear response of nitrate to NOx reduction in China during the COVID-19 pandemic".ATMOSPHERIC ENVIRONMENT 264(2021).