ROx Budgets and O3 Formation during Summertime at Xianghe Suburban Site in the North China Plain

Photochemical smog characterized by high concentrations of ozone (O3) is a serious air pollution issue in the North China Plain (NCP) region, especially in summer and autumn. For this study, measurements of O3, nitrogen oxides (NOx), volatile organic compounds (VOCs), carbon monoxide (CO), nitrous acid (HONO), and a number of key physical parameters were taken at a suburban site, Xianghe, in the NCP region during the summer of 2018 in order to better understand the photochemical processes leading to O3 formation and find an optimal way to control O3 pollution. Here, the radical chemistry and O3 photochemical budget based on measurement data from 1-23 July using a chemical box model is investigated. The daytime (0600-1800 LST) average production rate of the primary radicals referred to as ROx (OH + HO2+ RO2) is 3.9 ppbv h-1. HONO photolysis is the largest primary ROx source (41％). Reaction of NO2 + OH is the largest contributor to radical termination (41％), followed by reactions of RO2 + NO2 (26％). The average diurnal maximum O3 production and loss rates are 32.9 ppbv h-1 and 4.3 ppbv h-1, respectively. Sensitivity tests without the HONO constraint lead to decreases in daytime average primary ROx production by 55％ and O3 photochemical production by 42％, highlighting the importance of accurate HONO measurements when quantifying the ROx budget and O3 photochemical production. Considering heterogeneous reactions of trace gases and radicals on aerosols, aerosol uptake of HO2 contributes 11％ to ROx sink, and the daytime average O3 photochemical production decreases by 14％. The O3-NOx-VOCs sensitivity shows that the O3 production at Xianghe during the investigation period is mainly controlled by VOCs.     

Numerical study on the impacts of heterogeneous reactions on ozone formation in the Beijing urban area

The air quality model CMAQ-MADRID （Community Multiscale Air Quality-Model of Aerosol Dynamics, Reaction, Ionization and Dissolution） was employed to simulate summer O3 formation in Beijing China, in order to explore the impacts of four heterogeneous reactions on O3 formation in an urban area. The results showed that the impacts were obvious and exhibited the characteristics of a typical response of a VOC-limited regime in the urban area. For the four heterogeneous reactions considered, the NO2 and HO2 heterogeneous reactions have the most severe impacts on O3 formation. During the O3 formation period, the NO2 heterogeneous reaction increased new radical creation by 30%, raising the atmospheric activity as more NO→NO2 conversion occurred, thus causing the O3 to rise. The increase of O3 peak concentration reached a maximum value of 67 ppb in the urban area. In the morning hours, high NO titration reduced the effect of the photolysis of HONO, which was produced heterogeneously at night in the surface layer. The NO2 heterogeneous reaction in the daytime is likely one of the major reasons causing the O3 increase in the Beijing urban area. The HO2 heterogeneous reaction accelerated radical termination, resulting in a decrease of the radical concentration by 44% at the most. O3 peak concentration decreased by a maximum amount of 24 ppb in the urban area. The simulation results were improved when the heterogeneous reactions were included, with the O3 and HONO model results close to the observations.     

2007和2008年夏季北京奥运馆大气PM10与PM2.5质量浓度变化特征

为了监测北京奥运主场馆附近大气颗粒物的污染状况以及评估奥运污染源减排措施对北京大气颗粒物质量浓度变化的影响,利用颗粒物在线监测仪器TEOM于2007年和2008年夏季,在奥运主场馆附近的中国科学院遥感应用研究所办公楼楼顶对大气颗粒物PM10和PM2.5进行了连续同步观测。结果表明,2007年夏季监测点附近大气PM10与PM2.5质量浓度的平均值分别为153.9和71.2μg.m-3,而2008年夏季PM10与PM2.5质量浓度的平均值分别为85.2和52.8μg.m-3。与奥运前一年同时段相比,奥运时段大气PM10和PM2.5的质量浓度分别下降44.5%和25.1%。对比分析奥运前后的2次典型污染过程发现,空气相对湿度的增加和偏南气流输送的共同影响易造成大气颗粒物的累积增长,而降雨的湿清除作用和偏北气流则会使大气颗粒物浓度迅速降低。在相近的气象条件下,奥运前后的污染过程中,大气细粒子的日均增长速率分别为25.1和13.9μg.m-3.d-1,而大气粗粒子的日均增长速率分别为20.8和2.2μg.m-3.d-1,奥运时段污染累积过程中大气粗、细粒子的增长速率分别显著低于和略低于奥运前同时段污染过程中颗粒物的增长速率。污染源减排措施的实施是奥运期间大气颗粒物质量浓度降低的主要原因,从控制效果来看,奥运期间实施的污染源减排措施对大气粗粒子的控制效果明显好于大气细粒子。     

Analysis of the Effect of Optical Properties of Black Carbon on Ozone in an Urban Environment at the Yangtze River Delta,China

Black carbon(BC) reduces the photolysis coefficient by absorbing solar radiation, thereby affecting the concentration of ozone(O_3) near the ground. The influence of BC on O_3 has thus received much attention. In this study, Mie scattering and the tropospheric Ultraviolet and Visible radiation model are used to analyze the effect of BC optical properties on radiation. Combined with data of O_3 precursors in Nanjing in 2014, an EKMA curve is drawn, and the variations in O_3 concentration are further investigated using a zero-dimensional box mechanism model(NCAR MM). When O_3 precursors are unchanged, radiation and O_3 show a highly similar tendency in response to changing BC optical properties(R=0.997).With the increase of modal radius, the attenuation of fresh BC to radiation and O_3 first trends upward before decreasing. In the mixing process, the attenuation of BC to radiation and O_3 presents an upward tendency with the increase of relative humidity but decreases rapidly before increasing slowly with increasing thickness of coating. In addition, mass concentration is another major factor. When the BC to PM2.5 ratio increases to 5% in Nanjing, the radiation decreases by approximately 0.13%–3.71% while O_3 decreases by approximately 8.13%–13.11%. The radiative effect of BC not only reduces O_3 concentration but also changes the EKMA curve. Compared with the NOx control area, radiation has a significant influence on the VOCs control area. When aerosol optical depth(AOD) increases by 17.15%, the NOx to VOCs ratio decreases by 8.27%, and part of the original NOx control area is transferred to the VOCs control area.     

汾渭平原CUACE模式空气质量预报性能的检验订正及环境评估

利用2019年1—6月地面环境监测资料和PM_2.5气象条件评估指数，结合滚动偏差订正方法，对汾渭平原CUACE空气质量预报产品进行了检验订正，并对气象条件和污染减排影响进行了评估。结果表明：CUACE模式对空气质量指数(AQI)、PM_2.5和SO₂浓度预报值较接近观测值，PM₁₀、CO和NO₂预报值小于观测值，O₃预报值大于观测值；对首要污染物O₃和PM_2.5及重度和严重等级污染的预报的TS评分最高，漏报率和空报率最小，预报偏差最接近1；滚动偏差订正方法对改善CUACE空气质量预报效果较为明显，尤其是对PM₁₀、O₃和NO₂改善最为明显；汾渭平原2019年上半年气象条件变化使PM_2.5浓度较2018年同期和过去5年同期分别上升了18.26%和11.18%，减排措施使PM_2.5浓度较2018年同期和过去5年...     

北京春季沙尘和霾期间气溶胶的对比模拟研究

利用气象模式WRF驱动区域空气质量模式RAQMS,模拟研究了2014年北京地区春季颗粒物及气溶胶化学组分的时空变化,对比分析了沙尘期（3月17日、29日）和霾期（3月25～27日）的天气形势、气象要素和气溶胶化学组分特征,比较了沙尘和人为气溶胶表面非均相化学反应对大气化学成分的影响及相对贡献。结果显示,模式对于气象要素、PM2.5、PM10及其化学组分具有较好的模拟能力,考虑了气溶胶表面非均相化学反应后明显提高了模式对PM2.5及气溶胶化学组分模拟的准确性。沙尘期间,沙尘对PM10质量浓度贡献占主导地位（50.7%）,对PM2.5的贡献与有机气溶胶（OM）和人为排放的一次颗粒物（PPM）相当;霾期间,硝酸盐NO₃?（25.6%）和OM（23.6%）对PM2.5的贡献最大,在PM10中NO₃?、PPM和OM的贡献相当。沙尘期,粗粒子明显增加,在PM10中所占比例与细粒子相当,为45.5%;霾期,细粒子占主导地位,占PM10质量浓度的85.6%。非均相化学反应使沙尘期间硫酸盐（SO₄2–）和NO₃–浓度分别增加16.9%和83.8%,使霾期间的SO₄2?和NO₃–浓度分别增加14.5%和45.0%。2014年3月,非均相化学反应使北京月均SO₂、NO₂、O₃、SO₄2?、NH₄+和NO₃?的浓度分别变化了?2.5%、?5.7%、?3.4%、11.7%、18.6%和58.5%,本文结果表明非均相化学反应对二次无机气溶胶的生成有重要贡献。     

Effects of additional HONO sources on visibility over the North China Plain

The objective of the present study was to better understand the impacts of the additional sources of nitrous acid （HONO） on visibility, which is an aspect not considered in current air quality models. Simulations of HONO contributions to visibility over the North China Plain （NCP） during August 2007 using the fully coupled Weather Research and Forecasting/Chemistry （WRF/Chem） model were performed, including three additional HONO sources： （1） the reaction of photo-excited nitrogen dioxide （NO~） with water vapor; （2） the NO2 heterogeneous reaction on aerosol surfaces; and （3） HONO emissions. The model generally reproduced the spatial patterns and diurnal variations of visibility over the NCP well. When the additional HONO sources were included in the simulations, the visibility was occasionally decreased by 20%-30% （3-4 km） in local urban areas of the NCP. Monthly-mean concentrations of NO3, NH＋, SO]- and PM2.5 were increased by 20%-52% （3-11μg m-3）, 10%-38%, 6%-10%, and 6%-11% （9-17 μg m-3）, respectively; and in urban areas, monthly-mean accumulation- mode number concentrations （AMNC） and surface concentrations of aerosols were enhanced by 15%-20% and 10%-20%, respectively. Overall, the results suggest that increases in concentrations of PM2.5, its hydrophilic components, and AMNC, are key factors for visibility degradation. A proposed conceptual model for the impacts of additional HONO sources on visibility also suggests that visibility estimation should consider the heterogeneous reaction on aerosol surfaces and the enhanced atmospheric oxidation capacity due to additional HONO sources, especially in areas with high mass concentrations of NOx and aerosols.     

Particulate matter trends and quantification of the spring sand-dust contribution in Hohhot,Inner Mongolia,from 2013 to 2017

2013年9月国务院颁布了《大气污染防治行动计划》.研究其实施前后呼和浩特市大气污染物浓度变化及及原因;同时,分析了春季沙尘天气对于呼和浩特市大气环境颗粒物浓度的定量影响.结果表明:呼和浩特市大气环境质量持续改善,但大气污染物浓度仍然较高.PM2.5和PM10年均浓度分别超过国家二级标准22.9％和35.7％;2013-2017年春季PM2.5和PM10浓度降幅较大,沙尘天气对呼和浩特市PM2.5,PM10,和TSP浓度的绝对贡献范围分别在0.6-5.2μg m-3,9.0-16.9 μg m-3和 14.7-30.0 μg m-3.     

Observation-based Estimation of Aerosol-induced Reduction of Planetary Boundary Layer Height

Radiative aerosols are known to influence the surface energy budget and hence the evolution of the planetary boundary layer. In this study, we develop a method to estimate the aerosol-induced reduction in the planetary boundary layer height(PBLH) based on two years of ground-based measurements at a site, the Station for Observing Regional Processes of the Earth System(SORPES), at Nanjing University, China, and radiosonde data from the meteorological station of Nanjing. The observations show that increased aerosol loads lead to a mean decrease of 67.1 W m-2for downward shortwave radiation(DSR) and a mean increase of 19.2 W m-2for downward longwave radiation(DLR), as well as a mean decrease of 9.6W m-2for the surface sensible heat flux(SHF) in the daytime. The relative variations of DSR, DLR and SHF are shown as a function of the increment of column mass concentration of particulate matter(PM2.5). High aerosol loading can significantly increase the atmospheric stability in the planetary boundary layer during both daytime and nighttime. Based on the statistical relationship between SHF and PM2.5column mass concentrations, the SHF under clean atmospheric conditions(same as the background days) is derived. In this case, the derived SHF, together with observed SHF, are then used to estimate changes in the PBLH related to aerosols. Our results suggest that the PBLH decreases more rapidly with increasing aerosol loading at high aerosol loading. When the daytime mean column mass concentration of PM2.5reaches 200 mg m-2, the decrease in the PBLH at 1600 LST(local standard time) is about 450 m.     

沈阳两次降水过程中能见度的变化特征

利用2011年7月29-31日,8月27-29日沈阳大气成分观测站的能见度资料,统计分析了能见度与降水强度、PM₁₀、PM _2.5、PM _1.0质量浓度、风速、相对湿度等气象要素的相关性。结果表明: 7月29-31日降水过程特点为个别时间内降水量较大,8月27-29日降水过程特点为持续几个小时都有较大降水量;7月29-31日和8月27-29日降水过程中,初期降水对PM的湿清除效果较好,后期随着降水强度的增加,能见度有所降低;7月29日0时-31日23时期间内,PM质量浓度在降水过程中出现5 μg•m^-3左右的低值是因为降水和较大风速的双重作用,而8月27日0时-29日23时期间内的降水过程中,风速较稳定,PM质量浓度的改变量相对较小;7月29日-31日和8月27日-29日降水过程中,平均风速与PM₁₀、PM _2.5、PM _1.0的变化趋势均呈反相关,较高的相对湿度有利于PM质量浓度的上升;7月29-31日和8月27-29日降水过程中,能见度与PM _2.5/PM₁₀、PM _1.0/PM₁₀的比值变化趋势均呈明显的反相关。随着颗粒物粒径的减小,其与能见度的相关性逐渐增加。     

Enhancements of Major Aerosol Components Due to Additional HONO Sources in the North China Plain and Implications for Visibility and Haze

The Weather Research and Forecasting/Chemistry model(WRF-Chem) was updated by including photoexcited nitrogen dioxide(NO2) molecules,heterogeneous reactions on aerosol surfaces,and direct emissions of nitrous acid(HONO) in the Carbon-Bond Mechanism Z(CBM-Z).Five simulations were conducted to assess the effects of each new component and the three additional HONO sources on concentrations of major chemical components.We calculated percentage changes of major aerosol components and concentration ratios of gas NO y(NOyg) to NO y and particulate nitrates(NO-3) to NO y due to the three additional HONO sources in the North China Plain in August of 2007.Our results indicate that when the three additional HONO sources are included,WRF-Chem can reasonably reproduce the HONO observations.Heterogeneous reactions on aerosol surfaces are a key contributor to concentrations of HONO,nitrates(NO 3),ammonium(NH + 4),and PM 2.5(concentration of particulate matter of 2.5 μm in the ambient air) across the North China Plain.The three additional HONO sources produced a～5%-20% increase in monthly mean daytime concentration ratios of NO-3 /NO y,a ～15%-52% increase in maximum hourly mean concentration ratios of NO-3 /NO y,and a ～10%-50% increase in monthly mean concentrations of NO-3 and NH+4 across large areas of the North China Plain.For the Bohai Bay,the largest hourly increases of NO-3 exceeded 90%,of NH+4 exceeded 80%,and of PM 2.5 exceeded 40%,due to the three additional HONO sources.This implies that the three additional HONO sources can aggravate regional air pollution,further impair visibility,and enhance the incidence of haze in some industrialized regions with high emissions of NO x and particulate matter under favorable meteorological conditions.     

2018年春季西北五省省会城市大气质量与健康风险评价

城市大气污染及其引起的健康效应一直是关注的热点.本研究对2018年春季西北五省省会城市PM2.5、PM10、NO2、SO2、CO和O3浓度数据进行了系统分析,并采用美国环境保护署(United States Envi-ronmental Protection Agency,USEPA)推荐的健康风险评价模型评估了PM2...     

利用WRF-Chem模拟研究京津冀地区夏季大气污染物的分布和演变

应用WRF—Chem（Weather Research and Forecasting Model with Chemistry）模式模拟研究了2007年8月京津冀地区近地面O3、NO2、PM2.5浓度的时空变化特征,将模拟结果与观测数据进行详细对比,结果表明,模式可以较好地模拟O3、PM2.5,浓度的空间分布和时间变化特征,成功再现了8月33和PM2.5的几次积累增加过程,其中O,的模拟值与观测值的相关系数为0．69～0．86,PM2.5的相关系数为0．44～0．49,但模式对NO2的模拟相对较差,相关系数为0．27～0．43。北京、天津地区为O3月均低值区,月均体积浓度约30×10^-9,渤海及京津冀以西地区O3月平均体积浓度可达60×10^-9;PM2,呈现南高北低的分布特征,变化范围为120～240μg／m3。14时月平均03体积浓度在北京、天津地区低于周边地区,约为60×10^-9;而PM2.5质量浓度在环渤海地区和河北南部较高,为100～120μg/m^3。8月17日北京出现一次典型的高浓度O,污染事件,14时北京地区温度达到33℃,O3体积浓度为80×10^-9～110×10^-9。在局地排放、化学反应和外来输送的共同作用下,渤海西岸和北岸PM2.5的质量浓度超过120μg／m3,其中二次气溶胶质量浓度为50～100μg／m3,一次排放人为气溶胶质量浓度为10～20μg／m3,海盐质量浓度为1～7μg／m3,二次气溶胶是该地区PM2.5的主要贡献者。     

Impacts of the meteorological condition versus emissions reduction on the PM2 5 concentration over Beijing-Tianjin-Hebei during the COVID-19 lockdown

本研究从气象条件和减排两方面探讨了COVID-19封锁期间严重雾霾发生的原因[研究目的],并定量的分析了气象条件和减排对PM2.5浓度的相对影响[创新点].使用WRF-Chem在2019年2月3日-16日和2020年2月3日-16日进行了三个数值模拟试验,分别为2019年气象场与MEIC-2019(2019年中国多分辨...     

Characteristics of Aerosol Pollution Under Different Visibility Conditions in Winter in a Coastal Mega-City in China

To investigate chemical profiles and formation mechanisms of aerosol particles in winter haze events,comprehensive measurements including hourly concentrations of PM2.5 and water-soluble inorganic ions and related gasphase precursors were conducted via an online monitoring system from January to March of 2016 in Shenzhen, a coastal mega-city in south China. In this study, high concentrations of PM2.5, NO2 and lower levels of O3 were observed during haze periods in comparison with clear days(Visibility15 km). The major secondary ionic species were NH+4、NO-3 and SO2-4, which varied significantly on haze and clear days. The ratio of NO-3/SO2-4 in haze days was greater than that on clear days and tended to be larger when air pollution became more serious. At the same time, compared with previous studies, it has been found that the ratio has been increasing gradually in Shenzhen, indicating that the motor vehicle exhaust emissions have a more and more important impact on air quality in Shenzhen. Sulfur oxidation rate(SOR) and nitrogen oxidation rate(NOR) was higher during the haze period than that in clean days, indicating efficient gas to particle conversion. Further analysis shows that high concentrations of sulfate might be explained by aqueous oxidation,but gas-phase reactions might dominate nitrate formation. This study also highlights that wintertime nitrate formation can be an important contributor to aerosol particles, especially during haze periods.     

Probabilistic Automatic Outlier Detection for Surface Air Quality Measurements from the China National Environmental Monitoring Network

Although quality assurance and quality control procedures are routinely applied in most air quality networks, outliers can still occur due to instrument malfunctions, the influence of harsh environments and the limitation of measuring methods. Such outliers pose challenges for data-powered applications such as data assimilation, statistical analysis of pollution characteristics and ensemble forecasting. Here, a fully automatic outlier detection method was developed based on the probability of residuals, which are the discrepancies between the observed and the estimated concentration values. The estimation can be conducted using filtering——or regressions when appropriate——to discriminate four types of outliers characterized by temporal and spatial inconsistency, instrument-induced low variances, periodic calibration exceptions, and less PM10 than PM2.5 in concentration observations, respectively. This probabilistic method was applied to detect all four types of outliers in hourly surface measurements of six pollutants (PM2.5, PM10, SO2, NO2, CO and O3) from 1436 stations of the China National Environmental Monitoring Network during 2014-16. Among the measurements, 0.65%-5.68% are marked as outliers, with PM10 and CO more prone to outliers. Our method successfully identifies a trend of decreasing outliers from 2014 to 2016, which corresponds to known improvements in the quality assurance and quality control procedures of the China National Environmental Monitoring Network. The outliers can have a significant impact on the annual mean concentrations of PM2.5, with differences exceeding 10 μg m-3 at 66 sites.     

Smog Chamber Study on the Ozone Formation Potential of Acetaldehyde

Acetaldehyde is one of the important VOC species of O3 precursors in the atmospheric environment. The influences of relative humidity (RH) and initial VOC/NOx ratio (RCN) on the formation of O3 are studied in smog chamber experiments, and the MCM v3.3.1 mechanism of acetaldehyde is modified based on the experimental results. In low-RH conditions (RH= 11.6％±1.1％), the O3 concentration at 6 h increases first and then decreases with the increase of RCN, and the RCN at the inflection point of O3 concentrations is 3.2. In high-RH experiments (RH = 78.8％±1.0％), variation of the O3 concentration at 6 h with RCN is similar to that in low-RH experiments, but the RCN at the inflection point is 2.8. RH has no significant effect on the O3 concentrations under low RCN (< 3), whereas it has a negative effect under high RCN (> 3). Compared with the experimental results, original MCM v3.3.1 greatly underestimates the O3 concentrations. Addition of both the photolysis process of peroxyacetyl nitrate and the photolysis process of HNO3 on the reactor surface into the original MCM can reduce the difference between the simulated O3 concentrations and the experimental results at 6 h from 24％-35％ and 17％-49％ to 6％-26％ and 10％-42％ under low- and high-RH conditions, respectively. The maximum incremental reactivity (MIR) of acetaldehyde simulated with the modified MCM is 4.0 ppb ppb-1 without considering the effect of other VOCs.     

Reductions of PM<Subscript>2.5</Subscript> in Beijing-Tianjin-Hebei urban agglomerations during the 2008 Olympic Games

The Atmospheric Environmental Monitoring Network successfully undertook the task of monitoring the atmospheric quality of Beijing and its surrounding area during the 2008 Olympics.The results of this monitoring show that high concentrations of PM2.5 pollution exhibited a regional pattern during the monitoring period(1 June-30 October 2008).The PM2.5 mass concentrations were 53 μg m 3,66 μg m 3,and 82 μg m 3 at the background site,in Beijing,and in the Beijing-Tianjin-Hebei urban agglomerations,respectively.The PM2.5 levels were lowest during the 2008 Olympic Games(8-24 August):35 μg m 3 at the background site,42 μg m 3 in Beijing and 57 μg m 3 in the region.These levels represent decreases of 49%,48%,and 56%,respectively,compared to the prophase mean concentration before the Olympic Games.Emission control measures contributed 62%-82% of the declines observed in Beijing,and meteorological conditions represented 18%-38%.The concentration of fine particles met the goals set for a "Green Olympics."     

2014-2017年华北平原PM2.5组分消光与能见度对比研究

华北平原大气污染与低能见度状况一直是人们关切的问题.本文通过分析2014-2017年PM2.5化学成分的浓度和消光效果,研究了华北平原典型城市保定市的大气污染特征.结果表明,PM2.5组分的年均浓度显示下降趋势,水溶性无机离子,碳质气溶胶和金属元素分别减少了11 μg m-3,23μgm-3和1796 ng m-3.NH4+,NO3-和SO42-是PM2.5污染的主要污染物,三者之和占总离子浓度的82.9％.基于IMPROVE方程对细颗粒物进行重构,在观测期间PM2.5质量浓度平均为93±69μgm-3,春季,夏季,秋季和冬季的消光系数分别为373.8±233.6 M m-1,405.3±300.1 M m-1,554.3±378.2 M m-1和1005.2±750.3 M m-1.硫酸铵,硝酸铵和有机物对消光的贡献最大,不同季节下占比达55％～77％.通过PM2.5组分进行重构,利用IMPROVE算法计算得到Rbsca,用能见度测量值转换得到Vbsca,二者具有较高的相关性(r2=0.84);但存在Vbsca的高值被低估,Vbsca的低值被高估的现象;特别是当Rbsca＞1123 M m-1(对应能见度约小于2.0 km)时,Vbsca的值被低估了17.6％.高浓度PM2.5和高湿度对IMPROVE算法结果有显著的影响.     

长三角工业区夏季近地层臭氧和颗粒物污染相互关系研究

利用2013年5月15日到8月31日南京江北工业区（长三角典型工业区）同步的观测资料分析了近地层臭氧（O₃）和细颗粒物（PM_2.5）、气溶胶光学厚度（AOD）的变化特征及相互间的关系,并结合光化学箱模式分析了AOD对近地层O₃生成的影响。结果表明,观测期间PM_2.5平均质量浓度为56.2±20.1 μg m-3;AOD（500 nm）均值为1.4±0.9;波长指数α（440~870 nm）均值为1.0±0.3。PM_2.5质量浓度24 h均值超国家二级标准20.2%,超标时AOD均值增加14.7%,α平均值增加23.9%,O₃体积分数均值减少12.3%。O₃超国家二级标准10.1%,超标时段AOD增加34.9%,α变化不显著。高温低湿条件下,O₃日变化峰值（y）和PM_2.5质量浓度（x）存在较高的线性相关。相对湿度＜60%时,两者拟合曲线为y＝0.97x+43.96（拟合度R2=0.60）,温度＞32°C时,两者拟合方程为y＝1.24x+30.61（R2＝0.64）。夏季长三角工业区呈现高浓度O₃与高浓度PM_2.5叠加的大气复合污染。O₃日变化峰值和AOD变化呈显著负相关。模拟结果显示,O₃日变化峰值（y）和AOD（x）呈现极高的负相关[y＝－34.28x+181.62,R2 = 0.93或y＝220.62·exp (－x/3.17)－19.50,R2＝0.99]。