Progress of Research on Global Tropospheric Ozone Variation Characteristics during COVID-19 Pandemic

Xuewei HOU; Bin ZHU

doi:10.3878/j.issn.1006-9585.2022.22023

Volume 28 Issue 1

Jan. 2023

Turn off MathJax

Article Contents

Article Navigation > Climatic and Environmental Research > 2023 > 28(1): 103-116

HOU Xuewei, ZHU Bin. 2023. Progress of Research on Global Tropospheric Ozone Variation Characteristics during COVID-19 Pandemic [J]. Climatic and Environmental Research (in Chinese), 28 (1): 103−116 doi: 10.3878/j.issn.1006-9585.2022.22023

Citation:

PDF( 2232 KB)

Progress of Research on Global Tropospheric Ozone Variation Characteristics during COVID-19 Pandemic

doi: 10.3878/j.issn.1006-9585.2022.22023

Xuewei HOU,
Bin ZHU^,

Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Joint International Research Laboratory of Climate and Environment Change, Key Laboratory of Meteorological Disaster, Ministry of Education, Nanjing University of Information Science and Technology, Nanjing 210044

Funds: Innovative Research Group Project of National Natural Science Foundation of China (Grant 42021004), Nantional Key Research and Development Program of China (Grant 2022YFC3701204)

Received Date: 2022-02-21
Available Online: 2022-11-28
Publish Date: 2023-01-25

Abstract

Abstract

Restriction measures against coronavirus disease 2019 (COVID-19) caused atmospheric trace species to change, especially in relation to air pollution. This severe pollutant emission reduction phenomenon during the pandemic led to intensive studies on its behavior. Most studies evidence a decrease in all pollutants except for O₃. However, is this highlighted O₃ trend a global trend? This study summarized the research results in the past two years and explored the characteristics, mechanisms, and potential environmental effects of tropospheric O₃ and its precursors during the COVID-19 pandemic. During lockdown periods, global anthropogenic NO_x emissions decreased by at least 15%; especially, those in high-anthropogenic areas decreased by 18%–25%. In some highly polluted areas [volatile organic compound (VOC)-sensitive areas], NO_x emissions on the ground decreased by more than 50%. NO_x reduction led to the weakened titration effect of NO on O₃, leading to an increase in O₃ in such highly polluted areas (10%–50%). However, O₃ in remote areas and free troposphere (NO_x-sensitive areas) decreased, attributed to NO_x reduction and regional transmission effect. During the strict control period of the pandemic, surface O₃ was still increasing in most cities in China with significantly decreased NO_x concentration, indicating that the effective way to control surface O₃ concentration in urban areas in China is controlling O₃ precursors based on the sensitive area of O₃ chemical generation. However, the drastic change in NO_x in each region could change the sensitive area of O₃ chemical generation, leading to a change in O₃ production efficiency. However, due to the lack of VOC emission measurement and their atmospheric concentration, there are still great uncertainties in the trend and main controlling factors of O₃ in each region. In the future, the characteristics of O₃ in different regions and corresponding O₃ regulation strategies influenced by COVID-19 and global warming are also worthy of further study.
- COVID-19 pandemic,
- NO_x,
- Tropospheric O₃,
- Chemical sensitive area,
- Future change

FullText(HTML)

References(128)

References

[1]	Abalos M, Orbe C, Kinnison D E, et al. 2020. Future trends in stratosphere-to-troposphere transport in CCMI models [J]. Atmos. Chem. Phys., 20(11): 6883−6901. doi: 10.5194/acp-20-6883-2020
[2]	Ainsworth E A, Yendrek C R, Sitch S, et al. 2012. The effects of tropospheric ozone on net primary productivity and implications for climate change [J]. Annual Review of Plant Biology, 63: 637−661. doi: 10.1146/annurev-arplant-042110-103829
[3]	安俊岭. 2006. 北京近交通主干线地区的臭氧生成效率 [J]. 环境科学学报, 26(4): 652−657. doi: 10.3321/j.issn:0253-2468.2006.04.019 An J L. 2006. Ozone production efficiency in Beijing area with high NO_x emissions [J]. Acta Sci. Circum. (in Chinese), 26(4): 652−657. doi: 10.3321/j.issn:0253-2468.2006.04.019
[4]	Auvray M, Bey I. 2005. Long-range transport to Europe: Seasonal variations and implications for the European ozone budget [J]. J. Geophys. Res., 110(D11): D11303. doi: 10.1029/2004JD005503
[5]	Balamurugan V, Chen J, Qu Z, et al. 2021. Tropospheric NO₂ and O₃ response to COVID-19 lockdown restrictions at the national and urban scales in Germany [J]. J. Geophys. Res., 126(19): e2021JD035440. doi: 10.1029/2021JD035440
[6]	Bauwens M, Compernolle S, Stavrakou T, et al. 2020. Impact of coronavirus outbreak on NO₂ pollution assessed using TROPOMI and OMI observations [J]. Geophys. Res. Lett., 47(11): e2020GL087978. doi: 10.1029/2020GL087978
[7]	Bekbulat B, Apte J S, Millet D B, et al. 2021. Changes in criteria air pollution levels in the US before, during, and after Covid-19 stay-at-home orders: Evidence from regulatory monitors [J]. Sci. Total Environ., 769: 144693. doi: 10.1016/j.scitotenv.2020.144693
[8]	Bera B, Bhattacharjee S, Shit P K, et al. 2022. Variation and correlation between ultraviolet index and tropospheric ozone during COVID-19 lockdown over megacities of India [J]. Stochastic Environmental Research and Risk Assessment, 36(2): 409−427. doi: 10.1007/s00477-021-02033-w
[9]	Bouarar I, Gaubert B, Brasseur G P, et al. 2021. Ozone anomalies in the free troposphere during the COVID-19 pandemic [J]. Geophys. Res. Lett., 48(16): e2021GL094204. doi: 10.1029/2021GL094204
[10]	Bourgeois I, Peischl J, Neuman J A, et al. 2021. Large contribution of biomass burning emissions to ozone throughout the global remote troposphere [J]. Proc. Natl. Acad. Sci. USA, 118(52): e2109628118. doi: 10.1073/pnas.2109628118
[11]	Brandt J, Silver J D, Frohn L M, et al. 2012. An integrated model study for Europe and North America using the Danish Eulerian Hemispheric Model with focus on intercontinental transport of air pollution [J]. Atmos. Environ., 53: 156−176. doi: 10.1016/j.atmosenv.2012.01.011
[12]	Brasseur G P, Schultz M, Granier C, et al. 2006. Impact of climate change on the future chemical composition of the global troposphere [J]. J. Climate, 19(16): 3932−3951. doi: 10.1175/JCLI3832.1
[13]	Butler T M, Stock Z S, Russo M R, et al. 2012. Megacity ozone air quality under four alternative future scenarios [J]. Atmos. Chem. Phys., 12(10): 4413−4428. doi: 10.5194/acp-12-4413-2012
[14]	Cazorla M, Herrera E, Palomeque E, et al. 2021. What the COVID-19 lockdown revealed about photochemistry and ozone production in Quito, Ecuador [J]. Atmos. Pollut. Res., 12(1): 124−133. doi: 10.1016/j.apr.2020.08.028
[15]	Chang K L, Cooper O R, Gaudel A, et al. 2022. Impact of the COVID-19 economic downturn on tropospheric ozone trends: An uncertainty weighted data synthesis for quantifying regional anomalies above western North America and Europe [J]. AGU Advances, 3(2): e2021AV000542. doi: 10.1029/2021AV000542
[16]	Chen L W A, Chien L C, Li Y, et al. 2020. Nonuniform impacts of COVID-19 lockdown on air quality over the United States [J]. Sci. Total Environ., 745: 141105. doi: 10.1016/j.scitotenv.2020.141105
[17]	Choi Y, Souri A H. 2015. Seasonal behavior and long-term trends of tropospheric ozone, its precursors and chemical conditions over Iran: A view from space [J]. Atmos. Environ., 106: 232−240. doi: 10.1016/j.atmosenv.2015.02.012
[18]	Chossière G P, Xu H F, Dixit Y, et al. 2021. Air pollution impacts of COVID-19-related containment measures [J]. Sci. Adv., 7(21): eabe1178. doi: 10.1126/sciadv.abe1178
[19]	Clark H, Bennouna Y, Tsivlidou M, et al. 2021. The effects of the COVID-19 lockdowns on the composition of the troposphere as seen by In-service Aircraft for a Global Observing System (IAGOS) at Frankfurt [J]. Atmos. Chem. Phys., 21(21): 16237−16256. doi: 10.5194/acp-21-16237-2021
[20]	Collivignarelli M C, Abbà A, Bertanza G, et al. 2020. Lockdown for CoViD-2019 in Milan: What are the effects on air quality? [J]. Sci. Total Environ., 732: 139280. doi: 10.1016/j.scitotenv.2020.139280
[21]	Cooper O R, Parrish D D, Stohl A, et al. 2010. Increasing springtime ozone mixing ratios in the free troposphere over western North America [J]. Nature, 463(7279): 344−348. doi: 10.1038/nature08708
[22]	Cooper O R, Parrish D D, Ziemke J, et al. 2014. Global distribution and trends of tropospheric ozone: An observation-based review [J]. Elementa: Science of the Anthropocene, 2: 000029. doi: 10.12952/journal.elementa.000029
[23]	Cristofanelli P, Arduni J, Serva F, et al. 2021a. Negative ozone anomalies at a high mountain site in northern Italy during 2020: A possible role of COVID-19 lockdowns? [J]. Environ. Res. Lett., 16(7): 074029. doi: 10.1088/1748-9326/ac0b6a
[24]	Cristofanelli P, Gutiérrez I, Adame J A, et al. 2021b. Interannual and seasonal variability of NO_x observed at the Mt. Cimone GAW/WMO global station (2165 m a. s. l., Italy) [J]. Atmos. Environ., 249: 118245. doi: 10.1016/j.atmosenv.2021.118245
[25]	Cuesta J, Costantino L, Beekmann M, et al. 2022. Ozone pollution during the COVID-19 lockdown in the spring of 2020 over Europe, analysed from satellite observations, in situ measurements, and models [J]. Atmos. Chem. Phys., 22(7): 4471−4489. doi: 10.5194/acp-22-4471-2022
[26]	Davis D D, Crawford J, Chen G, et al. 1996. Assessment of ozone photochemistry in the western North Pacific as inferred from PEM-West A observations during the fall 1991 [J]. J. Geophys. Res., 101(D1): 2111−2134. doi: 10.1029/95JD02755
[27]	Derwent R G, Utembe S R, Jenkin M E, et al. 2015. Tropospheric ozone production regions and the intercontinental origins of surface ozone over Europe [J]. Atmos. Environ., 112: 216−224. doi: 10.1016/j.atmosenv.2015.04.049
[28]	Ding A J, Wang T, Thouret V, et al. 2008. Tropospheric ozone climatology over Beijing: Analysis of aircraft data from the MOZAIC program [J]. Atmos. Chem. Phys., 8(1): 1−13. doi: 10.5194/acp-8-1-2008
[29]	Ding J, van der A R J, Eskes H J, et al. 2020. NO_x emissions reduction and rebound in China due to the COVID-19 crisis [J]. Geophys. Res. Lett., 47(19): e2020GL089912. doi: 10.1029/2020GL089912
[30]	Dommen J, Prévôt A S H, Hering A M, et al. 1999. Photochemical production and aging of an urban air mass [J]. J. Geophys. Res., 104(D5): 5493−5506. doi: 10.1029/1998JD100053
[31]	El-Sayed M M H, Elshorbany Y F, Koehler K. 2021. On the impact of the COVID-19 pandemic on air quality in Florida [J]. Environ. Pollut., 285: 117451. doi: 10.1016/j.envpol.2021.117451
[32]	Elshorbany Y F, Kapper H C, Ziemke J R, et al. 2021. The status of air quality in the United States during the COVID-19 pandemic: A remote sensing perspective [J]. Remote Sens., 13(3): 369. doi: 10.3390/rs13030369
[33]	Emmons L K, Hess P G, Lamarque J F, et al. 2012. Tagged ozone mechanism for MOZART-4, CAM-chem and other chemical transport models [J]. Geosci. Model Dev., 5(6): 1531−1542. doi: 10.5194/gmd-5-1531-2012
[34]	Fadnavis S, Dhomse S, Ghude S, et al. 2014. Ozone trends in the vertical structure of Upper Troposphere and Lower stratosphere over the Indian monsoon region [J]. Int. J. Environ. Sci. Technol., 11(2): 529−542. doi: 10.1007/s13762-013-0258-4
[35]	Feng S Z, Jiang F, Wang H M, et al. 2020. NO_x emission changes over China during the COVID-19 epidemic inferred from surface NO₂ observations [J]. Geophys. Res. Lett., 47(19): e2020GL090080. doi: 10.1029/2020GL090080
[36]	Fioletov V, McLinden C A, Griffin D, et al. 2022. Quantifying urban, industrial, and background changes in NO₂ during the COVID-19 lockdown period based on TROPOMI satellite observations [J]. Atmos. Chem. Phys., 22(6): 4201−4236. doi: 10.5194/acp-22-4201-2022
[37]	Fiore A M, Naik V, Spracklen D V, et al. 2012. Global air quality and climate [J]. Chem. Soc. Rev., 41(19): 6663−6683. doi: 10.1039/c2cs35095e
[38]	Fu F, Purvis-Roberts K L, Williams B. 2020. Impact of the COVID-19 pandemic lockdown on air pollution in 20 major cities around the world [J]. Atmosphere, 11(11): 1189. doi: 10.3390/atmos11111189
[39]	Gaubert B, Bouarar I, Doumbia T, et al. 2021. Global changes in secondary atmospheric pollutants during the 2020 COVID-19 pandemic [J]. J. Geophys. Res., 126(8): e2020JD034213. doi: 10.1029/2020JD034213
[40]	Ghahremanloo M, Lops Y, Choi Y, et al. 2021. Impact of the COVID-19 outbreak on air pollution levels in East Asia [J]. Sci. Total Environ., 754: 142226. doi: 10.1016/j.scitotenv.2020.142226
[41]	Grange S K, Lee J D, Drysdale W S, et al. 2021. COVID-19 lockdowns highlight a risk of increasing ozone pollution in European urban areas [J]. Atmos. Chem. Phys., 21(5): 4169−4185. doi: 10.5194/acp-21-4169-2021
[42]	Guenther A B, Monson R K, Fall R. 1991. Isoprene and monoterpene emission rate variability: Observations with eucalyptus and emission rate algorithm development [J]. J. Geophys. Res., 96(D6): 10799−10808. doi: 10.1029/91JD00960
[43]	Guicherit R, Roemer M. 2000. Tropospheric ozone trends [J]. Chemosphere-Global Change Science, 2(2): 167−183. doi: 10.1016/S1465-9972(00)00008-8
[44]	Hirsch A I, Munger J W, Jacob D J, et al. 1996. Seasonal variation of the ozone production efficiency per unit NO_x at Harvard Forest, Massachusetts [J]. J. Geophys. Res., 101(D7): 12659−12666. doi: 10.1029/96JD00557
[45]	胡建林, 张远航. 2005. 长江三角洲地区臭氧生成过程分析 [J]. 环境科学研究, 18(2): 13−18. doi: 10.3321/j.issn:1001-6929.2005.02.003 Hu J L, Zhang Y H. 2005. Process analysis of ozone formation in the Yangtze River Delta [J]. Research of Environmental Sciences (in Chinese), 18(2): 13−18. doi: 10.3321/j.issn:1001-6929.2005.02.003
[46]	Huang X, Ding A J, Gao J, et al. 2021. Enhanced secondary pollution offset reduction of primary emissions during COVID-19 lockdown in China [J]. Natl. Sci. Rev., 8(2): nwaa137. doi: 10.1093/nsr/nwaa137
[47]	Huang Y H, Zhou J L, Yu Y, et al. 2020. Uncertainty in the impact of the COVID-19 pandemic on air quality in Hong Kong, China [J]. Atmosphere, 11(9): 914. doi: 10.3390/atmos11090914
[48]	Jacob D J, Logan J A, Murti P P. 1999. Effect of rising Asian emissions on surface ozone in the United States [J]. Geophys. Res. Lett., 26(14): 2175−2178. doi: 10.1029/1999GL900450
[49]	Jaffe D, Anderson T, Covert D, et al. 1999. Transport of Asian air pollution to North America [J]. Geophys. Res. Lett., 26(6): 711−714. doi: 10.1029/1999GL900100
[50]	Ju M J, Oh J, Choi Y H. 2021. Changes in air pollution levels after COVID-19 outbreak in Korea [J]. Sci. Total Environ., 750: 141521. doi: 10.1016/j.scitotenv.2020.141521
[51]	Keller C A, Evans M J, Knowland K E, et al. 2021. Global impact of COVID-19 restrictions on the surface concentrations of nitrogen dioxide and ozone [J]. Atmos. Chem. Phys., 21(5): 3555−3592. doi: 10.5194/acp-21-3555-2021
[52]	Kissler S M, Tedijanto C, Goldstein E, et al. 2020. Projecting the transmission dynamics of SARS-CoV-2 through the postpandemic period [J]. Science, 368(6493): 860−868. doi: 10.1126/science.abb5793
[53]	Kleinman L I, Daum P H, Lee Y N, et al. 2001. Sensitivity of ozone production rate to ozone precursors [J]. Geophys. Res. Lett., 28(15): 2903−2906. doi: 10.1029/2000GL012597
[54]	Kleinman L I, Daum P H, Lee Y N, et al. 2002. Ozone production efficiency in an urban area [J]. J. Geophys. Res., 107(D23): 4733. doi: 10.1029/2002JD002529
[55]	Kotelnikov S N, Stepanov E V. 2021. Anomalous dynamics of tropospheric ozone in the spring of 2020 in Central Russia [J]. Bull. Lebedev Phys. Inst., 48(3): 92−96. doi: 10.3103/S1068335621030076
[56]	Kriegler E, O’Neill B C, Hallegatte S, et al. 2012. The need for and use of socio-economic scenarios for climate change analysis: A new approach based on shared socio-economic pathways [J]. Global Environmental Change, 22(4): 807−822. doi: 10.1016/j.gloenvcha.2012.05.005
[57]	Kroll J H, Heald C L, Cappa C D, et al. 2020. The complex chemical effects of COVID-19 shutdowns on air quality [J]. Nature Chemistry, 12(9): 777−779. doi: 10.1038/s41557-020-0535-z
[58]	Lee J D, Drysdale W S, Finch D P, et al. 2020. UK surface NO₂ levels dropped by 42% during the COVID-19 lockdown: Impact on surface O₃ [J]. Atmos. Chem. Phys., 20(24): 15743−15759. doi: 10.5194/acp-20-15743-2020
[59]	Li H C, Chen K S, Huang C H, et al. 2010. Meteorologically adjusted long-term trend of ground-level ozone concentrations in Kaohsiung County, southern Taiwan [J]. Atmos. Environ., 44(29): 3605−3608. doi: 10.1016/j.atmosenv.2010.04.011
[60]	Li K, Jacob D J, Liao H, et al. 2021. Ozone pollution in the North China Plain spreading into the late-winter haze season [J]. Proc. Natl. Acad. Sci. USA, 118(10): e2015797118. doi: 10.1073/PNAS.2015797118
[61]	Li X Y, Liu J F, Mauzerall D L, et al. 2014. Effects of trans-Eurasian transport of air pollutants on surface ozone concentrations over Western China [J]. J. Geophys. Res., 119(21): 12338−12354. doi: 10.1002/2014JD021936
[62]	Lin Y K, Lin T H, Chang S C. 2010. The changes in different ozone metrics and their implications following precursor reductions over northern Taiwan from 1994 to 2007 [J]. Environ. Monit. Assess., 169(1–4): 143–157. doi: 10.1007/s10661-009-1158-4
[63]	Liu F, Page A, Strode S A, et al. 2020. Abrupt decline in tropospheric nitrogen dioxide over China after the outbreak of COVID-19 [J]. Sci. Adv., 6(28): eabc2992. doi: 10.1126/sciadv.abc2992
[64]	Liu H Y, Jacob D J, Bey I, et al. 2003. Transport pathways for Asian pollution outﬂow over the Paciﬁc: Interannual and seasonal variations [J]. J. Geophys. Res., 108(D20): 8786. doi: 10.1029/2002JD003102
[65]	Liu S C, Trainer M, Fehsenfeld F C, et al. 1987. Ozone production in the rural troposphere and the implications for regional and global ozone distributions [J]. J. Geophys. Res., 92(D4): 4191−4207. doi: 10.1029/JD092iD04p04191
[66]	Lokhandwala S, Gautam P. 2020. Indirect impact of COVID-19 on environment: A brief study in Indian context [J]. Environ. Res., 188: 109807. doi: 10.1016/j.envres.2020.109807
[67]	Lu X, Ye X P, Zhou M, et al. 2021. The underappreciated role of agricultural soil nitrogen oxide emissions in ozone pollution regulation in North China [J]. Nat. Commun., 12(1): 5021. doi: 10.1038/s41467-021-25147-9
[68]	Lund M T, Myhre G, Samset B H. 2019. Anthropogenic aerosol forcing under the Shared Socioeconomic Pathways [J]. Atmos. Chem. Phys., 19(22): 13827−13839. doi: 10.5194/acp-19-13827-2019
[69]	Marwah M, Agrawala P K. 2022. COVID-19 lockdown and environmental pollution: An Indian multi-state investigation [J]. Environ. Monit. Assess., 194(2): 49. doi: 10.1007/s10661-021-09693-9
[70]	Matthias V, Quante M, Arndt J A, et al. 2021. The role of emission reductions and the meteorological situation for air quality improvements during the COVID-19 lockdown period in central Europe [J]. Atmos. Chem. Phys., 21(18): 13931−13971. doi: 10.5194/acp-21-13931-2021
[71]	Menut L, Bessagnet B, Siour G, et al. 2020. Impact of lockdown measures to combat Covid-19 on air quality over western Europe [J]. Sci. Total Environ., 741: 140426. doi: 10.1016/j.scitotenv.2020.140426
[72]	Mertens M, Jöckel P, Matthes S, et al. 2021. COVID-19 induced lower-tropospheric ozone changes [J]. Environ. Res. Lett., 16(6): 064005. doi: 10.1088/1748-9326/abf191
[73]	Miyazaki K, Bowman K, Sekiya T, et al. 2021. Global tropospheric ozone responses to reduced NO_x emissions linked to the COVID-19 worldwide lockdowns [J]. Sci. Adv., 7(24): eabf7460. doi: 10.1126/sciadv.abf7460
[74]	Monks P S, Archibald A T, Colette A, et al. 2015. Tropospheric ozone and its precursors from the urban to the global scale from air quality to short-lived climate forcer [J]. Atmos. Chem. Phys., 15(15): 8889−8973. doi: 10.5194/acp-15-8889-2015
[75]	Moss R H, Edmonds J A, Hibbard K A, et al. 2010. The next generation of scenarios for climate change research and assessment [J]. Nature, 463(7282): 747−756. doi: 10.1038/nature08823
[76]	Newell R E, Evans M J. 2000. Seasonal changes in pollutant transport to the North Pacific: The relative importance of Asian and European sources [J]. Geophys. Res. Lett., 27(16): 2509−2512. doi: 10.1029/2000GL011501
[77]	Nunnermacker L J, Imre D, Daum P H, et al. 1998. Characterization of the Nashville urban plume on July 3 and July 18, 1995 [J]. J. Geophys. Res., 103(D21): 28129−28148. doi: 10.1029/98JD01961
[78]	Nussbaumer C M, Pozzer A, Tadic I, et al. 2022. Tropospheric ozone production and chemical regime analysis during the COVID-19 lockdown over Europe [J]. Atmos. Chem. Phys., 22(9): 6151−6165. doi: 10.5194/acp-22-6151-2022
[79]	Oltmans S J, Lefohn A S, Harris J M, et al. 2006. Long-term changes in tropospheric ozone [J]. Atmos. Environ., 40(17): 3156−3173. doi: 10.1016/j.atmosenv.2006.01.029
[80]	Oltmans S J, Lefohn A S, Shadwick D, et al. 2013. Recent tropospheric ozone changes—A pattern dominated by slow or no growth [J]. Atmos. Environ., 67: 331−351. doi: 10.1016/j.atmosenv.2012.10.057
[81]	Ordóñez C, Garrido-Perez J M, García-Herrera R. 2020. Early spring near-surface ozone in Europe during the COVID-19 shutdown: Meteorological effects outweigh emission changes [J]. Sci. Total Environ., 747: 141322. doi: 10.1016/j.scitotenv.2020.141322
[82]	Pan S, Jung J, Li Z T, et al. 2020. Air quality implications of COVID-19 in California [J]. Sustainability, 12(17): 7067. doi: 10.3390/su12177067
[83]	Parrish D D, Law K S, Staehelin J, et al. 2012. Long-term changes in lower tropospheric baseline ozone concentrations at northern mid-latitudes [J]. Atmos. Chem. Phys., 12(23): 11485−11504. doi: 10.5194/acp-12-11485-2012
[84]	Patel H, Talbot N, Salmond J, et al. 2020. Implications for air quality management of changes in air quality during lockdown in Auckland (New Zealand) in response to the 2020 SARS-CoV-2 epidemic [J]. Sci. Total Environ., 746: 141129. doi: 10.1016/j.scitotenv.2020.141129
[85]	Pathakoti M, Muppalla A, Hazra S, et al. 2020. An assessment of the impact of a nation-wide lockdown on air pollution—A remote sensing perspective over India [J]. Atmos. Chem. Phys. doi: 10.5194/acp-2020-621
[86]	Pepe E, Bajardi P, Gauvin L, et al. 2020. COVID-19 outbreak response, a dataset to assess mobility changes in Italy following national lockdown [J]. Scientific Data, 7(1): 230. doi: 10.1038/s41597-020-00575-2
[87]	Peralta O, Ortínez-Alvarez A, Torres-Jardón R, et al. 2021. Ozone over Mexico City during the COVID-19 pandemic [J]. Sci. Total Environ., 761: 143183. doi: 10.1016/j.scitotenv.2020.143183
[88]	Pochanart P, Akimoto H, Kajii Y, et al. 2003. Regional background ozone and carbon monoxide variations in remote Siberia/East Asia [J]. J. Geophys. Res., 108(D1): 4028. doi: 10.1029/2001JD001412
[89]	Riahi K, Rao S, Krey V, et al. 2011. RCP 8.5—A scenario of comparatively high greenhouse gas emissions [J]. Climatic Change, 109(1–2): 33–57. doi: 10.1007/s10584-011-0149-y
[90]	Ryerson T B, Buhr M P, Frost G J, et al. 1998. Emissions lifetimes and ozone formation in power plant plumes [J]. J. Geophys. Res., 103(D17): 22569−22583. doi: 10.1029/98JD01620
[91]	Shi X Q, Brasseur G P. 2020. The response in air quality to the reduction of Chinese economic activities during the COVID-19 outbreak [J]. Geophys. Res. Lett., 47(11): e2020GL088070. doi: 10.1029/2020GL088070
[92]	Sicard P, De Marco A, Agathokleous E, et al. 2020. Amplified ozone pollution in cities during the COVID-19 lockdown [J]. Sci. Total Environ., 735: 139542. doi: 10.1016/j.scitotenv.2020.139542
[93]	Siciliano B, Dantas G, da Silva C M, et al. 2020. Increased ozone levels during the COVID-19 lockdown: Analysis for the city of Rio de Janeiro, Brazil [J]. Sci. Total Environ., 737: 139765. doi: 10.1016/j.scitotenv.2020.139765
[94]	Smith S J, Wigley T M L. 2006. Multi-gas forcing stabilization with MiniCAM [J]. Energy Journal, 27(Special Issue): 373–391. doi: 10.5547/ISSN0195-6574-EJ-VolSI2006-NoSI3-19
[95]	Steinbrecht W, Kubistin D, Plass-Dülmer C, et al. 2021. COVID-19 crisis reduces free tropospheric ozone across the Northern Hemisphere [J]. Geophys. Res. Lett., 48(5): e2020GL091987. doi: 10.1029/2020GL091987
[96]	Stevenson D S, Young P J, Naik V, et al. 2013. Tropospheric ozone changes, radiative forcing and attribution to emissions in the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) [J]. Atmos. Chem. Phys., 13(6): 3063−3085. doi: 10.5194/acp-13-3063-2013
[97]	Stratoulias D, Nuthammachot N. 2020. Air quality development during the COVID-19 pandemic over a medium-sized urban area in Thailand [J]. Sci. Total Environ., 746: 141320. doi: 10.1016/j.scitotenv.2020.141320
[98]	Sudo K, Takahashi M, Akimoto H. 2003. Future changes in stratosphere–troposphere exchange and their impacts on future tropospheric ozone simulations [J]. Geophys. Res. Lett., 30(24): 2256. doi: 10.1029/2003GL018526
[99]	Tarasick D, Galbally I E, Cooper O R, et al. 2019. Tropospheric Ozone Assessment Report: Tropospheric ozone from 1877 to 2016, observed levels, trends and uncertainties [J]. Elementa: Science of the Anthropocene, 7: 39. doi: 10.1525/elementa.376
[100]	Tavella R A, da Silva Júnior F M R. 2021. Watch out for trends: Did ozone increased or decreased during the COVID-19 pandemic? [J]. Environ. Sci. Pollut. Res., 28(47): 67880−67885. doi: 10.1007/s11356-021-17142-w
[101]	Thielmann A, Prévôt A S H, Staehelin J. 2002. Sensitivity of ozone production derived from field measurements in the Italian Po basin [J]. J. Geophys. Res., 107(D22): 8194. doi: 10.1029/2000JD000119
[102]	van Vuuren D P, Lucas P L, Hilderink H. 2007. Downscaling drivers of global environmental change: Enabling use of global SRES scenarios at the national and grid levels [J]. Global Environmental Change, 17(1): 114−130. doi: 10.1016/j.gloenvcha.2006.04.004
[103]	Venter Z S, Aunan K, Chowdhury S, et al. 2020. COVID-19 lockdowns cause global air pollution declines [J]. Proc. Natl. Acad. Sci. USA, 117(32): 18984−18990. doi: 10.1073/pnas.2006853117
[104]	Verstraeten W W, Neu J L, Williams J E, et al. 2015. Rapid increases in tropospheric ozone production and export from China [J]. Nature Geoscience, 8(9): 690−695. doi: 10.1038/ngeo2493
[105]	Wang H L, Huang C, Tao W, et al. 2022. Seasonality and reduced nitric oxide titration dominated ozone increase during COVID-19 lockdown in eastern China [J]. npj Climate and Atmospheric Science, 5(1): 24. doi: 10.1038/s41612-022-00249-3
[106]	Wang H L, Tan Y, Zhang L X, et al. 2021. Characteristics of air quality in different climatic zones of China during the COVID-19 lockdown [J]. Atmos. Pollut. Res., 12(12): 101247. doi: 10.1016/J.APR.2021.101247
[107]	Wang L Q, Li M Y, Yu S C, et al. 2020. Unexpected rise of ozone in urban and rural areas, and sulfur dioxide in rural areas during the coronavirus city lockdown in Hangzhou, China: Implications for air quality [J]. Environ. Chem. Lett., 18(5): 1713−1723. doi: 10.1007/s10311-020-01028-3
[108]	Wang T, Wei X L, Ding A J, et al. 2009. Increasing surface ozone concentrations in the background atmosphere of Southern China, 1994–2007 [J]. Atmos. Chem. Phys., 9(16): 6217−6227. doi: 10.5194/acp-9-6217-2009
[109]	Wang Y H, Logan J A, Jacob D J. 1998. Global simulation of tropospheric O₃-NO_x-hydrocarbon chemistry: 2. Model evaluation and global ozone budget [J]. J. Geophys. Res., 103(D9): 10727−10755. doi: 10.1029/98JD00157
[110]	Webster M D, Babiker M, Mayer M, et al. 2002. Uncertainty in emissions projections for climate models [J]. Atmos. Environ., 36(22): 3659−3670. doi: 10.1016/S1352-2310(02)00245-5
[111]	Wild O, Akimoto H. 2001. Intercontinental transport of ozone and its precursors in a three-dimensional global CTM [J]. J. Geophys. Res., 106(D21): 27729−27744. doi: 10.1029/2000JD000123
[112]	Wild O, Pochanart P, Akimoto H. 2004. Trans-Eurasian transport of ozone and its precursors [J]. J. Geophys. Res., 109(D11): D11302. doi: 10.1029/2003JD004501
[113]	Xie B, Zhang H, Yang D D, et al. 2016. A modeling study of effective radiative forcing and climate response due to increased methane concentration [J]. Advances in Climate Change Research, 7(4): 241−246. doi: 10.1016/j.accre.2016.12.001
[114]	Xing J, Li S W, Jiang Y Q, et al. 2020. Quantifying the emission changes and associated air quality impacts during the COVID-19 pandemic on the North China Plain: A response modeling study [J]. Atmos. Chem. Phys., 20(22): 14347−14359. doi: 10.5194/acp-20-14347-2020
[115]	徐晓斌, 葛宝珠, 林伟立. 2009. 臭氧生成效率(OPE)相关研究进展 [J]. 地球科学进展, 24(8): 845−853. doi: 10.3321/j.issn:1001-8166.2009.08.001 Xu X B, Ge B Z, Lin W L. 2009. Progresses in the research of ozone production efficiency (OPE) [J]. Advances in Earth Science (in Chinese), 24(8): 845−853. doi: 10.3321/j.issn:1001-8166.2009.08.001
[116]	Yang Y, Ren L L, Li H M, et al. 2020. Fast climate responses to aerosol emission reductions during the COVID-19 pandemic [J]. Geophys. Res. Lett., 47(19): e2020GL089788. doi: 10.1029/2020GL089788
[117]	Yin H, Liu C, Hu Q H, et al. 2021. Opposite impact of emission reduction during the COVID-19 lockdown period on the surface concentrations of PM2.5 and O₃ in Wuhan, China [J]. Environ. Pollut., 289: 117899. doi: 10.1016/j.envpol.2021.117899
[118]	Young P J, Archibald A T, Bowman K W, et al. 2013. Pre-industrial to end 21st century projections of tropospheric ozone from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) [J]. Atmos. Chem. Phys., 13(4): 2063−2090. doi: 10.5194/acp-13-2063-2013
[119]	Yue X, Unger N. 2014. Ozone vegetation damage effects on gross primary productivity in the United States [J]. Atmos. Chem. Phys., 14(17): 9137−9153. doi: 10.5194/acp-14-9137-2014
[120]	Zangari S, Hill D T, Charette A T, et al. 2020. Air quality changes in New York City during the COVID-19 pandemic [J]. Sci. Total Environ., 742: 140496. doi: 10.1016/j.scitotenv.2020.140496
[121]	Zanis P, Ganser A, Zellweger C, et al. 2007. Seasonal variability of measured ozone production efficiencies in the lower free troposphere of Central Europe [J]. Atmos. Chem. Phys., 7(1): 223−236. doi: 10.5194/acp-7-223-2007
[122]	Zaveri R A, Berkowitz C M, Kleinman L I, et al. 2003. Ozone production efficiency and NO_x depletion in an urban plume: Interpretation of field observations and implications for evaluating O₃-NO_x-VOC sensitivity [J]. J. Geophys. Res., 108(D14): 4436. doi: 10.1029/2002JD003144
[123]	Zhang K, Liu Z Q, Zhang X J, et al. 2022. Insights into the significant increase in ozone during COVID-19 in a typical urban city of China [J]. Atmos. Chem. Phys., 22(7): 4853−4866. doi: 10.5194/acp-22-4853-2022
[124]	Zhang Q Q, Pan Y P, He Y X, et al. 2021. Substantial nitrogen oxides emission reduction from China due to COVID-19 and its impact on surface ozone and aerosol pollution [J]. Sci. Total Environ., 753: 142238. doi: 10.1016/j.scitotenv.2020.142238
[125]	Zhao F, Liu C, Cai Z N, et al. 2021. Ozone profile retrievals from TROPOMI: Implication for the variation of tropospheric ozone during the outbreak of COVID-19 in China [J]. Sci. Total Environ., 764: 142886. doi: 10.1016/j.scitotenv.2020.142886
[126]	Zhu J, Chen L, Liao H, et al. 2021. Enhanced PM2.5 decreases and O₃ increases in China during COVID-19 lockdown by aerosol–radiation feedback [J]. Geophys. Res. Lett., 48(2): e2020GL090260. doi: 10.1029/2020GL090260
[127]	Zhu S Q, Poetzscher J, Shen J Y, et al. 2021. Comprehensive insights into O₃ changes during the COVID-19 from O₃ formation regime and atmospheric oxidation capacity [J]. Geophys. Res. Lett., 48(10): e2021GL093668. doi: 10.1029/2021GL093668
[128]	Zhu Y, Liu J, Wang T J, et al. 2017. The impacts of meteorology on the seasonal and interannual variabilities of ozone transport from North America to East Asia [J]. J. Geophys. Res., 122(20): 10612−10636. doi: 10.1002/2017JD026761