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1.
利用2010—2012年对流层臭氧（O3）及其多种前体物的卫星遥感资料和全球水汽再分析资料,研究东亚区域O3及其前体物的时空分布,以及在中国东部（分为南、北两部分）相关性的季节变化。结果表明:东亚区域NO2与CO的对流层柱含量均表现为冬季高、夏季低的时空变化形式。O3对流层柱含量夏季达到峰值,冬季为谷值。中国东部的北部与南部地区O3与NO2均在夏秋季呈正相关,冬春季呈负相关。夏季大部分地区NOx的光化学循环反应对O3生成有积极的促进作用,冬季大部分地区O3的光化学循环生成受到抑制。O3与CO在北部地区夏秋季和南部地区夏季正相关性最大,无论是在北部还是南部地区,O3与CO的相关性在轻污染情况下最大,而在重污染和背景情况下较小,表明重污染气团向下风方的输送更有利于O3的光化学生成。O3与水汽在北部和南部地区的多数时间均呈较显著的正相关性,而在南部地区夏季和北部地区冬季具有较大的负相关性,反映出不同的环流形式、气团来源及伴随的天气条件变化对O3分布的影响。 相似文献
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2013年6—9月在河北省固城站观测到多次夜间对流性天气伴随地面O3混合比快速抬升的过程,并引起次日清晨到中午O3混合比升高。大多数对流过程中,O3混合比在半小时内升高至60×10-9～80×10-9,同时NOx等反应性气体混合比下降,θse值降低,说明下沉气流将高空气团带到地面,造成了O3混合比的升高。通过再分析资料得到下沉气团基本来源于对流层中下层,这一结论与当地进行的一次飞机观测结果吻合。多数对流过程中固城站和北京城区地面O3混合比和θse值有相同的变化趋势和程度。根据观测结果,推测华北地区在夏季和初秋时,对流层中下层存在O3高值区,混合比约为60×10-9～80×10-9。对流性天气对地面O3抬升的影响区域与对流系统的影响范围有关,可达到中尺度范围。华北地区光化学污染严重,对流性天气引起的地面O3混合比抬升程度比较强,对环境的影响值得关注。 相似文献
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利用ACTIVE（aerosol and chemical transport in tropical convection）试验资料,取2006年1月20日澳大利亚北部达尔文岛附近发生的一次飑线强对流天气的AE17航次和2006年1月27日无对流天气的AE21航次飞行路径中的探测资料,对澳大利亚达尔文地区夏季风盛行期间发生的有无强对流发生时O3和CO浓度垂直分布变化进行对比,考察强对流性天气发生对O3和CO浓度垂直输送作用。深对流云内强烈的垂直上升运动将O3和CO等化学气体携带输送至对流层上部并在对流层顶堆积,从而在对流层上部产生浓度峰值。当有强对流发生,飞机进入对流云上层时,O3浓度和CO浓度升高,O3和CO浓度变率增大,在对流层上部浓度出现峰值;当飞机飞出对流云时,O3和CO浓度相对较低,在对流云外出现谷值。在无对流发生的条件下O3和CO浓度相对较小,浓度变率也较小,无峰值产生。分析表明:O3和CO浓度分布不仅与强对流的垂直输送作用关系密切,且与气象要素垂直和水平分布以及动力输送过程密切相关。 相似文献
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为了进一步了解青藏高原闪电的产生氮氧化物（LNOx）经由光化学反应对O3浓度变化及夏季O3低谷形成的可能影响,本文利用2005~2013年由OMI卫星得到的对流层NO2垂直浓度柱（NO2 VCD）、O3总浓度柱（TOC）和O3廓线以及星载光学瞬变探测器OTD和闪电成像仪LIS获取的总闪电数资料,对青藏高原和同纬度长江中下游地区的TOC和NO2 VCD月均值时空分布特征、闪电与NO2 VCD的相关性和O3的垂直分布特征及其与LNOx的关系进行了对比分析。结果表明,青藏高原的O3低谷主要出现在夏季和秋季,其TOC值比同纬度长江中下游地区低约10~15 DU（Dobson unit）。青藏高原NO2VCD总体较小,表现为夏高冬低的分布特征。青藏高原夏季O3浓度受南亚高压的影响总体呈减小趋势,但因强雷暴天气导致对流层中上部LNOx浓度升高,并随强上升气流向对流层顶输送,同时通过光化学反应使O3浓度增加,缩小了青藏高原和同纬度地区的O3浓度差,减缓了O3总浓度的下降,抑制了夏季O3低谷的进一步深化。 相似文献
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关中平原至陕北黄土高原海拔渐次升高,大气污染物分布、排放源和下垫面特征均有较大变化。利用陕西省由南至北西安、延安、榆林三市环境空气质量监测数据和气象观测数据及NCEP再分析产品,对2018年春末夏初(5月下旬至6月初)连续两次臭氧(O3)污染过程开展研究。结果表明：三市O3质量浓度(用C(O3)表示)皆呈昼高夜低的日变化特征;三市日均C(O3)表现出随海拔高度升高而增加的现象,即榆林最高,延安次之,西安最低,较高海拔的黄土高原高背景O3可能是榆林、延安C(O3)较高的重要原因。两次O3污染发生在大气环流由春季型向夏季型过渡阶段,陕西处于500 hPa暖性高脊、850 hPa偏南风主导、地面静稳晴热的天气形势下,有利于光化学O3生成以及大气低层O3区域输送,其中西安的光化学生成对其日间C(O3)升高作用最明显。三市温度和C(O3)呈正相关,相同温度下... 相似文献
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在我国当前臭氧和颗粒物复合污染的局面下，位于西北地区的宁夏回族自治区近年来夏季臭氧区域性污染突出，浓度高值区主要分布在银川都市圈(银川市、石嘴山市和吴忠市)。因此利用区域空气质量模式系统RAMS-CMAQ对2019年夏季6月银川都市圈臭氧污染问题开展数值模拟，定量探讨区域传输及垂直输送对O3浓度的贡献，为有效控制当地臭氧污染提供科学依据。结果表明：2019年6月银川都市圈O3浓度北高、中部低，与前体物的分布特征并不完全一致，表明O3的非线性效应以及背景O3传输潜在的贡献。水平方向上，银川都市圈本地排放源对近地面O3的贡献大都在20%～30%，仅灵武达40%以上，外界传输贡献均在30%以上。其中银川本地贡献较弱，相邻区域间存在输送影响，一定程度上减弱了该地区的本地贡献。此外，在夏季整体偏南风的影响下O3有较为明显的由南向北的输送作用。垂直方向上，郊区、城市和工业代表性站点O3浓度的变化趋势基本一致，各过程量贡献有所差异。夜晚O... 相似文献
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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(NOx)、二氧化硫(SO2)、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(O3)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O3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NOx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NOx的减少量达50%以上。NOx的减少导致NO对O3的滴定作用减弱,使得该类高污染地区O3增加(10%～50%)。而偏远地区及自由对流层O3主要受NOx控制,NOx... 相似文献
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以大豆“中黄-14”为试验材料, 利用OTC-1型农田开顶式气室, 首次模拟研究单独CO2和O3浓度倍增及其交互作用对大豆生物量、产量及其构成因子、同化产物分配形式和收获指数的影响。与未通CO2和O3的处理相比, 单独CO2浓度倍增对生物量、产量、荚果串数、荚数、籽粒数、籽粒重具有正效应, O3为明显的负效应, 通气时段越长效果越明显; 持续的CO2浓度和O3浓度倍增交互作用表现为CO2的影响大于O3; CO2和O3交互作用逐渐达到浓度倍增的处理, 由于O3剂量逐渐累积和阶段性增加, 对大豆刺激逐渐增强, 最终O3的负效应与CO2的正效应相近。单独O3浓度倍增抑制光合产物向根和籽粒的输送, 向叶茎的输送明显增强, 使根冠比 (RSR)、子粒与茎杆比 (GCR) 明显下降, 长期作用可使大豆收获指数 (HI) 减小, 叶重比 (LWR) 显著增加, 且随通气时间的延长影响增大; CO2浓度倍增及其交互作用对RSR、LWR、GCR和HI影响相对较小, 仅在±10%左右。 相似文献
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利用2015—2019年辽宁城市逐小时地面O3浓度观测数据,结合各城市逐小时气象要素观测数据,分析了辽宁地区近5 a的O3污染状况及影响O3的相关气象条件。结果表明：除环辽东湾部分城市O3浓度呈下降趋势外,辽宁地区其他城市的O3浓度均呈明显的上升趋势,O3正取代PM2.5成为影响辽宁地区的首要大气污染物。O3浓度具有夏季高、冬季低,下午高、早晨低的时间分布特征。除受污染排放源直接影响外,高温、高湿、强辐射、小风和地面低气压都有利于O3的局地生成;在亚洲夏季风的影响下,上游地区（如京津冀地区）的污染气团会随大气环流向东北地区输送,对辽宁地区夏季O3污染产生重要影响。 相似文献
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我国东部夏季一次强对流活动过程中对流层上部大气成分变化的分析 总被引：1，自引：0，他引：1
利用星载微波临边遥感探测结果,对2006年6月28～29日江淮地区的一次强对流天气过程中对流层上部一氧化碳 (CO) 、臭氧 (O3) 、水汽 (H2O) 和冰水含量 (IWC) 的分布特点进行了研究.强对流天气过程前后的对比分析表明,CO混合比增大,在200 hPa处增加了0.12 ppm (1 ppm=10-6);O3混合比减小,在70 hPa处减少了0.30 ppm;H2O混合比在250 hPa处增加了400 ppm;IWC在强降水发生之前有大幅增长,在200 hPa处最大含量可达0.03 g/m3.CO和O3含量与垂直运动速度两者的相关变化表明,对流垂直输送作用可能是造成对流层上层和平流层低层大气成分变化的机制之一.而H2O和IWC含量的增加主要局限于对流层顶以下,这表明对流层上部水物质的质量和形态是由垂直输送作用和对流系统内部的微物理过程共同决定的. 相似文献
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Middle Stratospheric Polar Vortex Ozone Budget during the Warming Arctic Winter, 2002--2003 总被引：1，自引：0，他引：1
The ozone budget inside the middle stratospheric polar vortex(24-36 km) during the 2002-2003 Arctic winter is studied by analyzing Michelson Interferometer for Passive Atmospheric Sounding(MIPAS) satellite data.A comprehensive global chemical transport model(Model for Ozone and Related Chemical Tracers,MOZART-3) is used to analyze the observed variation in polar vortex ozone during the stratospheric sudden warming(SSW) events.Both MIPAS measurement and MOZART-3 calculation show that a pronounced increase(26-28 DU) in the polar vortex ozone due to the SSW events.Due to the weakening of the polar vortex,the exchange of ozone mass across the edge of the polar vortex increases substantially and amounts to about 3.0× 107 kg according to MOZART-3 calculation.The enhanced downward transport offsets about 80% of polar vortex ozone mass increase by horizontal transport.A "passive ozone" experiment shows that only ～55% of the vertical ozone mass flux in February and March can be attributed to the variation in vertical transport.It is also shown that the enhanced downward ozone above ～32 km should be attributed to the springtime photochemical ozone production.Due to the increase of air temperature,the NOx reaction rate increases by 40%-80% during the SSW events.As a result,NOx catalytic cycle causes another 44% decrease in polar vortex ozone compared to the net ozone changes due to dynamical transport.It is also shown that the largest change in polar vortex ozone is due to horizontal advection by planetary waves in January 2003. 相似文献
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Climate changes induced by human activities have attracted a great amount of attention. With this, a coupling system of an atmospheric chemistry model and a climate model is greatly needed in China for better understanding the interaction between atmospheric chemical components and the climate. As the first step to realize this coupling goal, the three-dimensional global atmospheric chemistry transport model MOZART-2 (the global Model of Ozone and Related Chemical Tracers, version 2) coupled with CAM2 (the Community Atmosphere Model, version 2) is set up and the model results are compared against observations obtained in East Asia in order to evaluate the model performance. Comparison of simulated ozone mixing ratios with ground level observations at Minamitorishima and Ryori and with ozonesonde data at Naha and Tateno in Japan shows that the observed ozone concentrations can be reproduced reasonably well at Minamitorishima but they tend to be slightly overestimated in winter and autumn while underestimated a little in summer at Ryori. The model also captures the general features of surface CO seasonal variations quite well, while it underestimates CO levels at both Minamitorishima and Ryori. The underestimation is primarily associated with the emission inventory adopted in this study. Compared with the ozonesonde data, the simulated vertical gradient and magnitude of ozone can be reasonably well simulated with a little overestimation in winter, especially in the upper troposphere. The model also generally captures the seasonal, latitudinal and altitudinal variations in ozone concentration. Analysis indicates that the underestimation of tropopause height in February contributes to the overestimation of winter ozone in the upper and middle troposphere at Tateno. 相似文献
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利用2015—2019年中国东部20个省份222个城市的地面O_3观测数据和全球再分析风场数据,研究了中国东部地区O_3的时空分布特征,以及在亚洲夏季风背景下污染上风方O_3光化学输送对下风方O_3质量浓度季节变化的影响。结果表明:中国东部地区O_3质量浓度夏季高、冬季低,O_3质量浓度按照东南、华东、东北、华北的顺序依次升高,位于中高纬度的华北、东北地区明显高于位于中低纬度的华东、华南地区。不同城市、不同季节O_3质量浓度日变化形态具有较好的一致性,都表现为夜晚低、清晨逐渐升高、下午至黄昏达到最大的单周期变化形态,具有典型的光化学控制特征。春季,亚洲夏季风开始影响中国东部地区,华东、华北、东北地区为大范围的O_3高值区;夏季,亚洲夏季风将O_3及其前体物由纬度较低的华南、华东地区向纬度较高的华北、东北地区不断输送和累积,并在夏季强紫外辐射作用下发生光化学反应,导致夏季华北、东北地区的O_3污染。 相似文献
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Ozone throughout the troposphere is subject of significant temporal and spatial variability due to photochemical production in the planetary boundary layer and free troposphere, stratospheric intrusions, convective events and long range transport. However, high resolving observations of ozone in the troposphere are generally rare today. That is of special disadvantage for limited area models, which represent mathematically a differential equation system with an initial and boundary problem. As ozone concentrations usually increase from the earth surface to the stratosphere, a proper choice of the background ozone concentrations is necessary to reproduce or even predict the amount and distribution of ozone in a specific region of interest.In this paper the impact of background concentrations of ozone on regional scale model results is analysed during a summer smog episode over Europe. For this purpose ozone is artificially partitioned into individual categories. For each category, transport and chemical transformation is calculated separately. Initial and boundary concentrations of ozone dominate total ozone concentrations increasingly with height. But also in the planetary boundary layer they contribute with more than 30% to thetotal ozone changes and are therefore far from being negligible. Moderately modified assumptions of background ozone concentrations reveal an uncertainty of near surface ozone concentrations of 5–15%depending on the weather situation. 相似文献
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NO<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript> change over China and its influences 总被引：2，自引：0，他引：2
A 3-D chemical transport model (OSLO CTM2) is used to investigate the impact of the increase of NOx emission over China. The model is capable to reproduce basically the seasonal variation of surface NOx and ozone over eastern China. NOx emission data and observations reveal that NOx over eastern China increases quite quickly with the economic development of China. Model results indicate that NOx concentration over eastern China increasingly rises with the increase of NOx emission over China, and accelerates to increase in winter. When the NOx emission increases from 1995 to its double, the ratio of NO2/NOx abruptly drops in winter over northern China. Ozone at the surface decreases in winter with the continual enhancement of the NOx level over eastern China, but increases over southern China in summertime. It is noticeable that peak ozone over northern China increases in summer although mean ozone changes little. In summer, ozone increases in the free troposphere dominantly below 500 hPa.Moreover, the increases of total ozone over eastern China are proportional to the increases of NOx emission.In a word, the model results suggest that the relationship between NOx and ozone at the surface would change with NOx increase. 相似文献
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A NUMERICAL STUDY OF THE VARIATIONS AND DISTRIBUTIONS OF TROPOSPHERIC OZONE AND ITS PRECURSORS OVER CHINA* 
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下载免费PDF全文 By means of a three-dimensional meteorological model (MM5) and a chemical model,the distributions of tropospheric ozone and its precursors over China have been simulated in summer and winter time,16-18 August 1994 and 7-9 January 1995.The distribution of ozone over the Tibetan Plateau in summer time is deeply discussed.The simulated results indicate that thedistributions of surface ozone and NOx are in good agreement with observed results,and human activities and photochemical reactions are the main factors controlling the surface ozone and NOx concentrations.In addition,higher ozone concentrations are coincided with the air convergence,and the lower concentrations are related to the air divergence.In summer,over the Tibetan Plateau the strong flow convergence results in higher ozone concentrations in the lower troposphere:and the strong flow divergence results in lower ozone concentrations in the upper troposphere.In winter time ozone concentrations show large-scale characteristics controlled by westerly flow,and in the jet area they are lower than those outside the jet. 相似文献
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Craig Stroud Sasha Madronich Elliot Atlas Christopher Cantrell Alan Fried Brian Wert Brian Ridley Fred Eisele Lee Mauldin Richard Shetter Barry Lefer Frank Flocke Andy Weinheimer Mike Coffey Brian Heikes Robert Talbot Donald Blake 《Journal of Atmospheric Chemistry》2004,47(2):107-138
Local ozone production and loss rates for the arctic free troposphere (58–85° N, 1–6 km, February–May) during the TroposphericOzone Production about the Spring Equinox (TOPSE) campaign were calculated using a constrained photochemical box model. Estimates were made to assess the importance of local photochemical ozone production relative to transport in accounting for the springtime maximum in arctic free tropospheric ozone. Ozone production and loss rates from our diel steady-state box model constrained by median observations were first compared to two point box models, one run to instantaneous steady-state and the other run to diel steady-state. A consistent picture of local ozone photochemistry was derived by all three box models suggesting that differences between the approaches were not critical. Our model-derived ozone production rates increased by a factor of 28 in the 1–3 km layer and a factor of 7 in the 3–6 kmlayer between February and May. The arctic ozone budget required net import of ozone into the arctic free troposphere throughout the campaign; however, the transport term exceeded the photochemical production only in the lower free troposphere (1–3 km) between February and March. Gross ozone production rates were calculated to increase linearly with NOx mixing ratiosup to 300 pptv in February and for NOx mixing ratios up to 500 pptv in May. These NOx limits are an order of magnitude higher thanmedian NOx levels observed, illustrating the strong dependence ofgross ozone production rates on NOx mixing ratios for the majority of theobservations. The threshold NOx mixing ratio needed for netpositive ozone production was also calculated to increase from NOx 10pptv in February to 25 pptv in May, suggesting that the NOx levels needed to sustain net ozone production are lower in winter than spring. This lower NOx threshold explains how wintertime photochemical ozone production can impact the build-up of ozone over winter and early spring. There is also an altitude dependence as the threshold NOx neededto produce net ozone shifts to higher values at lower altitudes. This partly explains the calculation of net ozone destruction for the 1–3 km layerand net ozone production for the 3–6 km layer throughout the campaign. 相似文献
19.
将区域海气耦合模式RegCM3-POM和区域气候模式RegCM3 40年(1963-2002年)的模拟结果与NCEP/NCAR再分析资料进行对比,检验区域海气耦合模式对中国华北地区夏季大气水汽含量和水汽输送特征的模拟能力,比较耦合模式与单独区域气候模式的差异.结果表明,区域海气耦合模式RegCM3-POM的模拟性能相对于单独区域气候模式RegCM3,大气水汽输送特征的模拟能力有了较大的改进.分析显示两种模式都能够较好地再现东哑地区气候平均夏季大气水汽储量浅红和水汽输送的空间分布特征,而耦合模式对大气水汽输送的模拟更为合理.在对流层中低层更接近观测;耦合模式对中国华北地区夏季平均大气水汽输送通量在垂直方向卜的分布型及水平4个边界水汽输送收支的模拟,相对于单独大气模式有了一定的改进;耦合模式对伴随华北地区夏季早涝的大气水汽异常输送也具有较好的模拟能力,其模拟的水汽输送异常的来源与观测基本一致,尤其是在20°N以北地区,耦合模式结果相对于单独区域气候模式有了很大的改进.但同时耦合模式在低纬度海洋上对气候平均夏季大气水汽含量模拟的偏差比区域气候模式显著;与观测相比,耦合模式对来自孟加拉湾地区的大气水汽输送模拟偏弱,而对西太平洋副热带高压西侧水汽输送模拟偏强,与华北夏季旱涝相联系的水汽输送异常的模拟在低纬度海洋上也存在明显偏差. 相似文献
20.
Shu Li Tijian Wang Prodromos Zanis Dimitris Melas Bingliang Zhuang 《Acta Meteorologica Sinica》2018,32(2):279-287
The spatial distribution, radiative forcing, and climatic effects of tropospheric ozone in China during summer were investigated by using the regional climate model RegCM4. The results revealed that the tropospheric ozone column concentration was high in East China, Central China, North China, and the Sichuan basin during summer. The increase in tropospheric ozone levels since the industrialization era produced clear-sky shortwave and clear-sky longwave radiative forcing of 0.18 and 0.71 W m–2, respectively, which increased the average surface air temperature by 0.06 K and the average precipitation by 0.22 mm day–1 over eastern China during summer. In addition, tropospheric ozone increased the land–sea thermal contrast, leading to an enhancement of East Asian summer monsoon circulation over southern China and a weakening over northern China. The notable increase in surface air temperature in northwestern China, East China, and North China could be attributed to the absorption of longwave radiation by ozone, negative cloud amount anomaly, and corresponding positive shortwave radiation anomaly. There was a substantial increase in precipitation in the middle and lower reaches of the Yangtze River. It was related to the enhanced upward motion and the increased water vapor brought by strengthened southerly winds in the lower troposphere. 相似文献