新冠疫情影响下全球对流层臭氧变化特征研究进展  

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

作　　者：侯雪伟[1] 朱彬[1] HOU Xuewei;ZHU Bin(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)

机构地区：[1]南京信息工程大学气象灾害预报预警与评估协同创新中心/气候与环境变化国际合作联合实验室/气象灾害教育部重点实验室,南京210044

出　　处：《气候与环境研究》2023年第1期103-116,共14页Climatic and Environmental Research

基　　金：国家自然科学基金创新研究群体项目42021004;国家重点研发计划项目2022YFC3701204。

摘　　要：自2020年新冠疫情(COVID-19)爆发以来,各地进行了不同程度的人员流动限制或封控,致使全球范围内氮氧化物(NO_(x))、二氧化硫(SO_(2))、一氧化氮(CO)、细颗粒物(PM2.5)等大气污染物浓度均大幅度降低,而作为二次污染物的臭氧(O_(3))在各地区却表现出复杂的变化特征,成为研究热点.本研究总结了近两年该方向的研究成果,阐明了COVID-19期间对流层O_(3)及其前体物的变化特征、变化机制及其可能存在的潜在环境效应.COVID-19严控期,全球人为NO_(x)排放下量降了至少15%,特别是高人为活动影响区,下降了18%-25%,部分高污染地区(挥发性有机物敏感区)近地层NO_(x)的减少量达50%以上.NO_(x)的减少导致NO对O_(3)的滴定作用减弱,使得该类高污染地区O_(3)增加(10%-50%).而偏远地区及自由对流层O_(3)主要受NO_(x)控制,NO_(x)的减少以及区域传输作用使得偏远地区及自由对流层O_(3)呈现减少状态.其中,2020年4月和5月,由于NO_(x)排放量的减少导致自由对流层O_(3)体积混合比减少量高达10×10^(-9);2020年5月和6月,全球对流层O_(3)总量下降了约6 Tg(O_(3))(-2%),亚洲和美洲NO_(x)排放量的减少对全球对流层O_(3)减少具有重要贡献.疫情严控期,NO_(x)浓度大幅度下降的情况下,我国大部分城市近地面O_(3)仍处于增加状态,这表明控制我国城市地区近地面O_(3)浓度的有效手段是根据O_(3)化学生成敏感区来控制前体物,但O_(3)前体物的剧烈变化也可改变O_(3)化学生成敏感区,导致O_(3)生成效率(OPE)的变化,但由于相对欠缺VOCs排放量及其大气浓度的观测,各地区O_(3)的变化趋势和主控因素还存在很大的不确定性.此外,未来COVID-19疫情和全球变暖叠加背景下,不同地区O_(3)的变化特征和对应的O_(3)调控策略亦值得进一步深入探究.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 O_(3).However,is this highlighted O_(3) 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 O_(3) 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 O_(3),leading to an increase in O_(3) in such highly polluted areas(10%-50%).However,O_(3) 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 O_(3) was still increasing in most cities in China with significantly decreased NO_(x) concentration,indicating that the effective way to control surface O_(3) concentration in urban areas in China is controlling O_(3) precursors based on the sensitive area of O_(3) chemical generation.However,the drastic change in NO_(x) in each region could change the sensitive area of O_(3) chemical generation,leading to a change in O_(3) 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 O_(3) in each region.In the future,the characteristics of O_(3) in different regions and corresponding O_(3) regulation strategies influenced by COVID-19 and global warming are also worthy of furt

关 键 词：新冠疫情 氮氧化物 对流层臭氧 臭氧控制区 未来变化 

分 类 号：P402[天文地球—大气物理学与大气环境]