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1.
Jun LI Hongbin CHEN Zhanqing LI Pucai WANG Xuehua FAN Wenying HE Jinqiang ZHANG 《大气科学进展》2019,36(11):1235-1250
High-quality and continuous radiosonde, aerosol and surface meteorology datasets are used to investigate the statistical characteristics of meteorological parameters and their effects on aerosols. The data were collected at the Atmospheric Radiation Measurement Southern Great Plains climate research facility during 2000–15. The parameters and vertical distribution of temperature inversion layers were found to have strong diurnal and seasonal changes. For surface-based temperature inversion (SBI), the mean frequency and depth of temperature inversion layers were 39.4% and 198 m, respectively. The temperature difference between the top and bottom of SBI was 4.8℃, and so the temperature gradient was 2.4℃ (100 m)?1. The detailed vertical distributions of temperature inversion had been determined, and only the temperature inversion layers below 1000 m showed diurnal and seasonal variations. Mean surface aerosol number concentrations increased by 43.0%, 21.9% and 49.2% when SBIs were present at 0530, 1730 and 2330 LST, respectively. The effect of SBI on surface aerosol concentration was weakest in summer (18.1%) and strongest in winter (58.4%). During elevated temperature inversion events, there was no noticeable difference in surface aerosol number concentrations. Temperature differences and temperature gradients across SBIs correlated fairly well with aerosol number concentrations, especially for temperature gradients. The vertical distribution of aerosol optical properties with and without temperature inversions was different. Surface aerosol measurements were representative of the air within (below), but not above, SBIs and EIs. These results provide a basis for developing a boundary layer aerosol accumulation model and for improving radiative transfer models in the lower atmosphere. 相似文献
2.
N.B.A. Trivett L.A. Barrie J.W. Bottenheim J.‐P. Blanchet G. den Hartog R.M. Hoff 《大气与海洋》2013,51(3):341-376
Abstract Arctic haze has been attributed to industrial pollution released at mid‐latitudes. Our current understanding has been pieced together from routine meteorological data, ground‐based air chemistry observations and limited aircraft measurements. This study investigates the relationship between synoptic boundary‐layer meteorology and the composition of the near‐surface atmosphere during the polar sunrise at Alert, N.W.T. A secondary objective is to characterize the influence of local activity on the atmospheric composition at a site for a new baseline monitoring station and at a location where aerosol chemistry and grab‐flask samples for CO2 have been made for many years. Detailed measurements of the vertical distribution of aerosols were obtained from an upward‐looking lidar to complement the ground‐based measurements. Meteorological profiles of the near‐surface boundary layer were obtained from both free‐flying and tethered balloons. Near‐surface measurements were made of aerosol physical and chemical properties, O3, NO2, NO/NOx, Peroxyacetylnitrate (PAN) and hydrocarbons. The study period was characterized by prolonged periods with strong surface inversions, which were broken up occasionally by intrusions of cold air into the warmer air aloft. Lidar observations showed that ice crystals often accompanied aerosols and were responsible for reducing visibility below 30–40 km. There was a strong correlation between aerosol mass in the diameter size range 0.15 to 1.5 μm and total SO4 = . PAN found at concentrations of about 200 ppt(v) was the main carrier of atmospheric nitrogen. Aerosol trace elements were divisible into anthropogenic soil, mixed soil/anthropogenic sea salt and halogens. Vertical transport in the surface boundary layer, as regulated by the strength of the surface radiation inversion, may play an important role in influencing the chemical composition of the air at the ground. The location of the new baseline monitoring laboratory was found to be generally windier and warmer than the lower altitude weather station, and the influence of local activity was found to be minimal. 相似文献
3.
气溶胶的时空分布及其核化成云的转化过程是云降水物理研究的重点,也是气候变化中气溶胶间接效应关注的热点问题。利用2013～2014年期间在华北中部山西地区开展的9架次夏季晴天和积云天气情况下的气溶胶、云凝结核（CCN）及云滴数浓度观测资料,分析研究了气溶胶的垂直分布、谱分布、来源特征及其与云凝结核、云滴数浓度的转化关系。研究结果表明,大气边界层逆温层结对气溶胶、CCN垂直分布有重要影响,不同天气条件下气溶胶谱型在低层差异较大而高层基本一致;垂直方向上CCN数浓度与气溶胶数浓度有较好的相关性,过饱和度0.3%条件下CCN比率（云凝结核/凝结核）与气溶胶有效直径呈线性关系;积云云下气溶胶与云滴的线性拟合方程为y=1.3x?616.3,拟合相关系数为0.96,气溶胶转化为云滴的比率可达到47%。在过饱和度0.3%条件下,云下CCN与云滴的线性拟合方程为y=1.6x?473.8,拟合相关系数也为0.96,CCN转化为云滴的比率可达到69%。 相似文献
4.
Evolution of aerosol vertical distribution during particulate pollution events in Shanghai 
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下载免费PDF全文 A set of micro pulse lidar(MPL)systems operating at 532 nm was used for ground-based observation of aerosols in Shanghai in 2011.Three typical particulate pollution events(e.g.,haze)were examined to determine the evolution of aerosol vertical distribution and the planetary boundary layer(PBL)during these pollution episodes.The aerosol vertical extinction coefficient(VEC)at any given measured altitude was prominently larger during haze periods than that before or after the associated event.Aerosols originating from various source regions exerted forcing to some extent on aerosol loading and vertical layering,leading to different aerosol vertical distribution structures.Aerosol VECs were always maximized near the surface owing to the potential influence of local pollutant emissions.Several peaks in aerosol VECs were found at altitudes above 1 km during the dust-and bioburning-influenced haze events.Aerosol VECs decreased with increasing altitude during the local-polluted haze event,with a single maximum in the surface atmosphere.PM2.5 increased slowly while PBL and visibility decreased gradually in the early stages of haze events;subsequently,PM2.5 accumulated and was exacerbated until serious pollution bursts occurred in the middle and later stages.The results reveal that aerosols from different sources impact aerosol vertical distributions in the atmosphere and that the relationship between PBL and pollutant loadings may play an important role in the formation of pollution. 相似文献
5.
环球海洋大气气溶胶化学研究 III：金属形态和入海通量 总被引：8，自引：0，他引：8
中国第三次南极考察和环球科学考察，历经北太平洋、南太平洋、南极半岛海域、南大西洋、北印度洋、以及沿途近岸海域，共收集58个气溶胶样品，采用石墨炉原子吸收法分析其中的水可溶态和酸可溶态的Mn、Fe、Pb、Cu、Cd。气溶胶中金属表现明显陆源向大洋输送的浓度梯度，近岸海域上空金属含量大于大洋上空含量，北太平洋上空含量高于南太平洋和南极半岛海域。气溶胶中金属的水可溶程度，在近岸海域上空依次为Cd＞Mn＞Cu＞Fe＞Pb，百分比分量分别为39%，36%， 23%，14%和5.3%；在大洋上空依次为Cd＞Mn＞Fe＞Cu＞pb，百分比分量分别为62%，44%，11%，3.1%和2.5%。本文还计算和比较各观测海区上空金属从大气输入海水的通量。 相似文献
6.
辽宁地区大气气溶胶粒子的垂直分布特征 总被引：19，自引：3，他引：16
详细分析了１９９６、１９９７年春末夏初在辽宁省进行的大气气深胶飞机观测的０～５ｋｍ气深胶粒子数深度和尺度谱分布的垂直、水平变化,初步讨论了它们与温度和相对温度的关系。结果表明,混合层顶上下粒子数深度具有不同的垂直分布特征;粒子谱受不同形成机制影响,表现为多峰分布;水平方向上气溶胶粒子数浓度存在显著变化;温度层结和相对温度对气溶胶粒子的浓度和谱分布有明显影响。 相似文献
7.
北方局地夏末气溶胶光学特性综合观测分析 总被引：4，自引：1，他引：4
本文对中国北方相近地理经度不同纬度的三个试验点（内蒙草原生态定位站、北京、新乡）夏末季节大气气溶胶特性进行了地面粒子计数和整层光学遥感等综合观测。分析结果表明，这三个试验点地面和整层气溶胶数浓度通常有内蒙较小，北京居中，新乡最大的特征。文中提出了浓度比这个参量，它可以定量描述地面源气溶胶对整层大气气溶胶的相对贡献。据此分析可知内蒙地面源较弱，与该地区人类活动稀少相对应。由浓度比推测，新乡除近地面城市空气污染较严重外，滨临的黄河河面水汽蒸发作用也是促成气溶胶浓度增大的原因。 相似文献
8.
Characteristics of Aerosol Activation Efficiency and Aerosol and CCN Vertical Distributions in North China 下载免费PDF全文
下载免费PDF全文 By analyzing airborne observations over North China from 30 flights during spring and autumn of 2005-2007, characteristics of the vertical distributions of aerosol and cloud condensation nuclei (CCN) at 0.3% supersaturation in various locations of North China are investigated. The measurement samplings were conducted over different surfaces such as plains, plateau, and sea. The results show that the number concentration of accumulation mode aerosols was greater in autumn than in spring, but the reverse is true for CCN. This means that more aerosols with diameters smaller than 100 nm could be activated as CCN in spring, and this could induce higher aerosol activation efficiency. The aerosol activation efficiency over the plains near the Taihang Mountain was greater in spring than in autumn, and it was greater over sea than over land. The aerosol activation efficiency above the boundary layer over the Bashang Plateau was very low. Based on a fit of the negative exponential vertical distributions of aerosol and CCN, a spatial parameterization model of aerosol and CCN as well as aerosol activation efficiency over North China was proposed. The results show that aerosol activation efficiency was not clearly dependent on altitude because it was mainly affected by regional physical and chemical characteristics of aerosols and the ambient atmospheric conditions. The mean aerosol activation efficiency is 0.66, with values of 0.70 and 0.53 in spring and autumn,respectively. 相似文献
9.
Knowledge of the vertical distribution of aerosols in the free troposphere is important for estimating their impact on climate. In this study, direct observations of the vertical distribution of aerosols in the free troposphere are made using surface Micro-Pulse Lidar (MPL) measurements. The MPL measurements were made at the Loess Plateau (35.95°N, 104.1°E), which is near the major dust source regions of the Taklimakan and Gobi deserts. The vertical distribution of the MPL backscattering suggested that non-dust aerosols floated from ground level to an altitude of approximately 9 km around the source regions. Early morning hours are characterized by a shallow aerosol layer of a few hundred meters thick. As the day progresses, strong convective eddies transport the aerosols vertically to more than 1500 m.
Citation: Huang, J. P., Z. W. Huang, J. R. Bi, et al., 2008: Micro-pulse lidar measurements of aerosol vertical structure over the Loess Plateau, Atmos. Oceanic Sci. Lett., 1, 8-11 相似文献
10.
Yanjun Ma Hujia Zhao Yunsheng Dong Huizheng Che Xiaoxiao Li Ye Hong Xiaolan Li Hongbin Yang Yuche Liu Yangfeng Wang Ningwei Liu Cuiyan Sun 《Acta Meteorologica Sinica》2018,32(2):313-323
This study analyzes and compares aerosol properties and meteorological conditions during two air pollution episodes in 19–22 (E1) and 25–26 (E2) December 2016 in Northeast China. The visibility, particulate matter (PM) mass concentration, and surface meteorological observations were examined, together with the planetary boundary layer (PBL) properties and vertical profiles of aerosol extinction coefficient and volume depolarization ratio that were measured by a ground-based lidar in Shenyang of Liaoning Province, China during December 2016–January 2017. Results suggest that the low PBL height led to poor pollution dilution in E1, while the high PBL accompanied by low visibility in E2 might have been due to cross-regional and vertical air transmission. The PM mass concentration decreased as the PBL height increased in E1 while these two variables were positively correlated in E2. The enhanced winds in E2 diffused the pollutants and contributed largely to the aerosol transport. Strong temperature inversion in E1 resulted in increased PM2.5 and PM10 concentrations, and the winds in E2 favoured the southwesterly transport of aerosols from the North China Plain into the region surrounding Shenyang. The large extinction coefficient was partially attributed to the local pollution under the low PBL with high ground-surface PM mass concentrations in E1, whereas the cross-regional transport of aerosols within a high PBL and the low PM mass concentration near the ground in E2 were associated with severe aerosol extinction at high altitudes. These results may facilitate better understanding of the vertical distribution of aerosol properties during winter pollution events in Northeast China. 相似文献
11.
2016年11月13日在北京地区上空存在持续稳定的层状云天气背景下,利用飞机开展气溶胶粒径谱、化学组成、云滴谱等参量的垂直观测,研究该个例云底气溶胶的活化能力。结果表明:探测期间北京地区为轻度污染天气,地面气溶胶浓度(0.11~3 μm)达到4600 cm-3。云层高度为800~1200 m,云底气溶胶数浓度相对于近地面大幅度降低,有效粒径显著增大(0.3~0.6 μm)。同时,近地面气溶胶中疏水性的一次有机气溶胶贡献显著,而云底气溶胶中一次有机气溶胶的贡献大幅降低,无机组分和二次有机气溶胶的贡献明显增大,造成吸湿性参数κ由0.25(地面)增大至0.32(云底)。云中气溶胶和云滴的谱分布衔接较好,且两者的数浓度之和与云底气溶胶浓度一致,可分别代表未活化和已活化的粒子。基于云底气溶胶粒径谱和吸湿性参数计算得到不同过饱和比下云凝结核的活化率,通过与云中观测结果对比,反推得到云底过饱和度约为0.048%。 相似文献
12.
Characteristics of Anthropogenic Sulfate and Carbonaceous Aerosols over East Asia： Regional Modeling and Observation 总被引：3，自引：0，他引：3
The authors present spatial and temporal characteristics of anthropogenic sulfate and carbonaceous aerosols over East Asia using a 3-D coupled regional climate-chemistry-aerosol model, and compare the simulation with the limited aerosol observations over the region. The aerosol module consists of SO2, SO4^2-, hydrophobic and hydrophilic black carbon （BC） and organic carbon compounds （OC）, including emission, advections, dry and wet deposition, and chemical production and conversion. The simulated patterns of SO2 are closely tied to its emission rate, with sharp gradients between the highly polluted regions and more rural areas. Chemical conversion （especially in the aqueous phase） and dry deposition remove 60% and 30% of the total SO2 emission, respectively. The SO4^2- shows less horizontal gradient and seasonality than SO2, with wet deposition （60%） and export （27%） being two major sinks. Carbonaceous aerosols are spatially smoother than sulfur species. The aging process transforms more than 80% of hydrophobic BC and OC to hydrophilic components, which are removed by wet deposition （60%） and export （30%）. The simulated spatial and seasonal SO4^2-, BC and OC aerosol concentrations and total aerosol optical depth are generally consistent with the observations in rural areas over East Asia, with lower bias in simulated OC aerosols, likely due to the underestimation of anthropogenic OC emissions and missing treatment of secondary organic carbon. The results suggest that our model is a useful tool for characterizing the anthropogenic aerosol cycle and for assessing its potential climatic and environmental effects in future studies. 相似文献
13.
通过比较EMAC模式模拟结果和卫星观测结果证实了模式的可信性,进而利用模拟结果分析研究了2010～2012年青藏高原上空气溶胶光学厚度及其直接辐射强迫的时空分布规律。结果表明:所有气溶胶组分中,沙尘、水溶性气溶胶和气溶胶中液态水是高原的主要消光物质,三者年平均消光占比分别为0.27、0.20和0.49。2011年夏季纳布罗火山爆发,高空气溶胶消光在海拔14 km以上显著增强。青藏高原气溶胶在大气顶和地表的直接辐射强迫分布总体上由北向南递减,沙尘气溶胶在高原北部边缘大气顶产生正辐射强迫,气溶胶大气层直接辐射强迫对大气有增温效应,主要出现在沙尘含量高的地区。此外,受纳布罗火山爆发的影响,平流层气溶胶在2011年秋、冬季产生了明显较强的负辐射强迫,相比于无火山爆发的2010年和 2012年,青藏高原上空平流层气溶胶负辐射强迫在2011年秋季和冬季分别增加了55.50%和52.38%。 相似文献
14.
The structure of atmospheric boundary layer determines the ability of atmospheric dispersion and has an essential impact on airborne aerosols. In this paper, the data of a radio sounding experiment held in Dongguan National Meteorological Observation Station, which is in a coastal city in Pearl River Delta, as well as the data of atmospheric aerosols, were utilized in order to analyze the characteristics of atmospheric boundary layer and its effects on surface aerosol concentrations. The results are showed at follows: the local circulations, associated with dominant winds, made complex structures of atmospheric layers, as the cold air and systematic winds weakened in the end of a cold air event. Weakened wind shears and inversion layers, especially a strong near-surface inversion layer, remarkably diminished the atmospheric diffusion abilities and facilitated an especially high concentration of surface aerosols. The convergence line or weak shear line of sea breeze in the ground level helps weaken the atmospheric diffusion abilities and results in atmospheric aerosols accumulation. 相似文献
15.
Particle induced X-ray emission analysis (PIXE) has been applied to aerosol long-range transport studies. The combination of a size fractionating sampler and a multi-element technique has enabled the identification of the transport pathways of individual constituents over the Atlantic Ocean and Europe. Chemical and size distribution data were obtained for aerosols collected at different sampling sites for the ground layer and the free atmosphere. Evaluation of these data under the aspect of air mass history extended the elemental determination in long range transport. A statistical technique was introduced and used to succeed in the semi-quantitative determination of transported pollutants. 相似文献
16.
17.
B. A. Bodhaine E. G. Dutton J. J. DeLuisi G. A. Herbert G. E. Shaw A. D. A. Hansen 《Journal of Atmospheric Chemistry》1989,9(1-3):213-224
Measurements at Barrow during the second Arctic Gas and Aerosol Sampling Program (AGASP-II), conducted in April 1986, showed no rapid long-range transport from lower-latitude source regions to Barrow, and only limited vertical transport from above the boundary layer to the surface. New aerosol size distribution measurements in the 0.005–0.1 m diameter size range using a Nuclepore-filter diffusion battery apparatus showed a median diameter of about 0.01 m during times of high condensation nucleus (CN) concentrations. Aerosol black carbon concentrations exceeding 400 ng m–3 were detected at the surface and were more strongly correlated with CN concentrations than with aerosol scattering extinction (sp), suggesting that aerosol carbon was generally associated with small particles rather than large particles. Measurements at Barrow during AGASP-I, conducted in March–April 1983, showed a series of aerosol events detected at the ground that were caused by rapid long-range transport paths to the vicinity of Barrow from Eurasia. These events were strongly correlated with aerosol loading in the vertical column (optical depth). 相似文献
18.
昆明城市热岛效应立体分布特征 总被引：17，自引：10，他引：17
利用低纬高原城市昆明城内外垂直观测资料，探讨了低纬高原城市的城市气候立体分布特征，通过比较分析，得出如下初步结果：昆明城市热岛效应不仅在地面附近存在，而且在城市上空也存在；其城市热岛效应为夜间强，影响高度高（＞50m)；昼间弱，影响高度低（＜50m)；近地面强，上空弱；昆明城市区域的气温垂直分布昼间为随高度增高温度递减，而夜间为逆温分布；受昆明城市周边环境影响，昆明城市热岛效应最大值中心呈现随高度增高而偏多现象。如此的气温立体空间分布，将对城市污染扩散、建筑物的设计、城市节能等产生影响。 相似文献
19.
Simulationsof Aerosol Optical Properties to Top of Atmospheric Reflected Sunlight in the Near Infrared CO2 Weak Absorption Band 下载免费PDF全文
下载免费PDF全文 Over the Asian continent,high aerosol loading is critical to ensure the high accuracy of CO2 retrieval in the near infrared absorption band.Simulations were performed to explore the effect of light path modification by aerosol son the atmospheric CO2 near infrared band(6140-6270 cm-1).The Vector LInearized Discrete Ordinate Radiative Transfer（VLIDORT） model and the Line-By-Line Radiative Transfer Model（LBLRTM） were used for forward calculations.The U.S.standard atmosphere was used for atmospheric profiles.The results indicate that the aerosols caused similar effects to increases in CO2 in the planetary boundary layer and became more significant with aerosol layer rising while aerosol optical depth was 0.1.This effect will cause an over estimation of the CO2 mixing ratio in the retrieval process and an under estimation in the aerosol layer.The results also indicate that the effect of urban and industrial aerosols is smaller than that of non-absorbing and dust aerosols because of the nearly constant absorption properties in the near infrared band. 相似文献
20.
利用SBDART（Santa Barbara DISORT Atmospheric Radiative Transfer）辐射传输模式,结合AERONET（Aerosol Robotic Network）北京站观测的气溶胶光学特性数据,评估北京地区近十年气溶胶以及黑碳气溶胶的辐射强迫,主要研究结果如下:北京近十年气溶胶平均光学厚度（aerosol optical depth, AOD440nm）为0.61±0.56,?ngstr?m波长指数均值为1.09,单次散射反照率（single scattering albedo, SSA440nm）的均值为0.888±0.045;AOD呈现下降趋势,SSA呈上升趋势,表明该区域气溶胶污染有所改善。晴空条件下,大气层顶、地面和大气的气溶胶直接辐射强迫多年均值分别为?24.91±19.80 W m?2、?65.52±43.78 W m?2、40.61±28.62 W m?2,即气溶胶对大气层顶和地表为冷却效应,对大气产生加热作用。气溶胶和黑碳气溶胶的直接辐射强迫绝对值的年际变化表现为微弱的下降趋势,季节变化特征为春夏季高,冬季低,这与AOD的变化规律一致。并且黑碳气溶胶的直接辐射强迫下降趋势与SSA的上升趋势呈现较好的反位相关系。 相似文献