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1.
大气边界层物理与大气环境过程研究进展 总被引：3，自引：2，他引：1
总结了近5年来中国科学院大气物理研究所大气边界层物理和大气化学国家重点实验室(LAPC)在第二代超声风速温度仪研制、城市边界层研究、复杂地形大气边界层探测与数值模拟、湍流机理研究、大气污染模式发展与应用等领域的主要进展,其中,第二代超声风速温度仪的野外对比测试结果表明其主要性能完全达到了国际先进水平;北京城市化发展使得北京325 m气象塔周边近地面流场已经具备了典型城市粗糙下垫面的流场特征,近地面夏季平均风速呈现非常明显的逐年递减趋势;北京沙尘暴大风时期湍流运动主要是小尺度湍涡运动,而大风的概率分布偏离高斯分布,风速较大的一侧概率分布呈指数迅速衰减,大风中风速很大的部分具有分形特征;珠穆朗玛峰北坡地区两次综合强化探测实验是迄今为止在青藏高原大型山地中实施的针对山地环流和物质／能量交换最为全面和连续的大气过程探测实验;白洋淀地区的观测研究表明,非均匀边界层具有一般边界层不具备的特点,无论是边界层结构还是湍流输送方面,水、陆边界层之间存在一定的差异,凸显其地表非均匀性的作用;为了解决不同尺度、不同类型的大气污染问题和实际应用,研制或发展完善了多套大气污染模式系统,包括全球大气化学模式、区域大气污染数值模式、城市大气污染数值模式和微小尺度(如街区尺度)范围内污染物输送扩散模式。 相似文献
2.
山区复杂地形上区域大气质量模式的试验研究 总被引：3，自引：3，他引：3
由于复杂地形上的气流多变，所以，进行区域空气质量模拟是比较困难的。根据大气污染总量控制和环境规划的需要，发展了一种可适用于山谷城市的大气质量模式，该模式的主要特点；（１）采用目前尚少的复杂地形上的三维边界层模式作为大气扩散模式所需城三维边界层要素场；（２）用复杂地形上的三维以模式和斯扩散氏架源（包括面源）和主架源所造在的地面ＳＯ２浓度，然后将两者的模拟浓度在相应网各上叠加。验证结果表明，该混合模式 相似文献
3.
Interaction between local and regional pollution during Escompte 2001: impact on surface ozone concentrations (IOP2a and 2b) 总被引：2，自引：0，他引：2
Escompte, a European programme which took place in the Marseille region in June–July 2001, has been designed as an exhaustive database to be used for the development and validation of air pollution models. The air quality Mesoscale NonHydrostatic Chemistry model (Meso-NH-C) is used to simulate 2 days of an Intensive Observation Period (IOP) documented during the Escompte campaign, June 23 and 24, 2001. We first study the synoptic and local meteorological situation on June 23 and 24, using surface and aircraft measurements. Then, we focus on the pollution episode of June 24. This study emphasizes the deep impact of synoptic and local dynamics on observed ozone concentrations. It is shown that ozone levels are due both to regional and local factors, with highlights of the importance of ozone layering. More generally this confirms, even in an otherwise predominant local sea-breeze regime, the need to consider larger scale regional pollutant transport. 相似文献
4.
Ozone episodes (> 100 ppbv) were observed frequently in Jinan, an urban site located between the highly polluted Yangtze Delta and Beijing–Tianjin region in East China. In this study, the ozone episodes observed in 2004 were analysed using the Hybrid Single-particle Lagrangian Integrated Trajectory (HYSPLIT) model and surface meteorological data, as well as Air Pollution Index (API). The meteorological conditions of episode days and non-episode days were compared and examined, and categorization of 6 groups of backward trajectories was performed. The results show that, most episodes were caused by local photochemical production (e.g., induced by sufficient sunshine duration and high temperature) and pollutant accumulation (e.g., induced by little rainfall and low wind speed), and transport of pollutants from the highly polluted regions could significantly influence the air quality at the site, especially from Yangtze Delta region. In addition, three typical ozone episodes were analysed using HYSPLIT model to infer any long-distance transport and surface meteorological data to infer the local ozone production potential. At last, the functions and inadequacies about the usage of HYSPLIT model combined with surface meteorological data for the analysis of photochemical pollution were discussed. 相似文献
5.
Very low ozone episodes due to polar vortex displacement 总被引：1，自引：0，他引：1
P. M. JAMES D. PETERS D. W. WAUGH 《Tellus. Series B, Chemical and physical meteorology》2000,52(4):1123-1137
6.
城市大气污染物扩散模拟系统开发 总被引：9，自引：14，他引：9
简单介绍了一个应用于复杂地形，下垫面条件下的中尺度大气污染物扩散模式的开发和利用；并为城市大气质量数值模拟和预测的实施，以兰州为例进行了初步的理想数值试验，其结果将对改进模式和城市污染源描述提供依据并积累经验，同时这也是最终形成城市大气质量预测系统的前期工作。 相似文献
7.
大城市气溶胶对光化辐射通量及臭氧的影响研究(Ⅱ)——数值试验分析 总被引：8，自引：8，他引：8
城市化已引起大量痕量气态污染物、气溶胶以及臭氧前体物的人为排放,从而引起区域大气化学循环的扰动变化。在分析国内外研究现状与观测实例的基础上,进一步用辐射模式与化学模式研究了气溶胶对到达地面的光化辐射通量以及臭氧形成的影响,表明气溶胶可显著减小到达地面的光化学辐射通量,减缓光化学反应进程,并进一步抑制臭氧的形成;在目前广州等大城市的污染过程中,高浓度的气溶胶可造成光化学辐射通量衰减高达70%~80%,紫外线的衰减比可见光更明显,在可见光波段随波长增大衰减幅度减小,气溶胶层的存在对短波长激发的光化学过程的影响更加显著。分析说明城市污染大气中光化学反应的生成物与反应物之间存在自抑制过程,在目前的城市群复合污染情况下,气溶胶与臭氧之间的非线性相互作用值得关注。 相似文献
8.
大气环境数值模拟研究新进展 总被引：14，自引：1，他引：13
近五年来,中国科学院大气物理研究所(简称大气所)在大气环境数值模拟方面取得了丰硕的成果,通过自主发展和引进,建立了完备的多尺度、多成分的大气环境数值模式,包括全球大气化学输送模式、区域和城市空气质量预报模式。大气所利用这些模式研究各种空间尺度上污染物浓度时空分布以及污染物的输送和演变,研究了多种污染过程的成因和污染变化规律,在污染物输送、低对流层臭氧高污染、区域及城市污染等方面取得了很多成果,并对区域或城市空气质量进行业务化实时预报。大气所还拓展了我国大气环境模拟研究的新领域:大气化学资料同化、污染模式集合预报、污染源反演新方法。初步建立了空气质量模式的资料同化系统(分别基于最优插值技术和集合卡曼滤波技术)和多模式集合预报体系,提高了模式预报水平;在污染源反演新方法方面进行了初步的探索。结合我国目前仍然面临着的大气环境问题,对今后大气环境数值模式的发展方向进行了展望。 相似文献
9.
南昌市环境空气臭氧污染现状分析 总被引：2，自引：0，他引：2
利用南昌市省外办环境空气监测点2003—2006年臭氧监测资料,使用综合污染指数法和国家《环境空气质量标准》进行分析评价。分析结果表明,南昌市省外办监测点环境空气中臭氧污染已经达到一定程度,2006年臭氧年日均值达0.203 mg/m3,年日均值超标率为12.63%;臭氧污染指数为2.03,污染负荷高达53.88%,比目前最为关注的污染物(可吸入颗粒物)污染负荷高39.07%。臭氧已成为城市环境空气中的主要污染物之一,尤其是每年的9月和10月,其污染更为严重。建议全省各城市积极创造条件开展环境空气臭氧监测,并纳入必测项目参加评价;环保部门应加强与气象部门的合作,科学分析江西环境空气臭氧污染原因,提出防治措施。 相似文献
10.
利用2014—2017年梅州城区的O3监测数据和相关气象观测资料,对本地区的O3的变化特征及影响O3的气象条件进行了相关分析。分析表明:梅州地区2014—2017年O3超标日数维持稳定水平,O3二级超标日数全部集中在春季和夏季; O3二级超标天数占AQI超标日数的比例快速上升,O3二级超标主要发生在3—8月,最多的是4月,O3是影响梅州市区空气质量重要因素。O3的月平均浓度与同期气温、日照显著正相关,与同期的气压呈显著负相关; O3污染过程中,O3的逐日浓度与同期气温、日照显著正相关,与同期的总云量、低云量、湿度呈显著负相关; O3污染过程中,O3浓度与地面及高空天气形势配置关系密切,O3浓度变化是多种气象要素共同作用的结果。 相似文献
11.
Net surface longwave radiation (NSLR) is one of key meteorological factors and is strongly influenced by cloud cover, surface temperature, humidity, and local micrometeorological conditions as well as terrain conditions. Realistically estimating NSLR is vitally important for understanding surface radiation balance and investigating micrometeorological factors of air pollution dispersion, especially in regions with complicated terrain. In this study, we proposed a distributed model for estimating NSLR by considering effects of complex local terrain conditions in China. Meteorological data (including mean temperature, relative humidity, and sunshine percentage) and observed NSLR data from 1993 to 2001 together with the digital elevation model data were used to parametrize the model and account for the effects of atmospheric factors and surface terrain factors according to the isotropic principle. The monthly NSLR during 1961–2000 was estimated at a spatial resolution of 1 km. Topographic analysis suggests that the distribution characteristics of NSLR with elevation or slope are consistent with those of field observations. In particular, the estimated NSLR is favorably comparable with site-level observations on the Tibetan Plateau (average relative error < 11%). Our results indicate that this model can describe microscale distribution features in mountainous areas in detail and that this improved approach can be used for NSLR spatial estimation in other regions with complicated terrain. 相似文献
12.
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
13.
A puff model is developed in this study, which simultaneously considers the Monte-Carlo technique, the time and space changes of atmospheric parameters, multiple continuity pollutant sources, linear chemical trans-formation and removal of pollutants, and the effect of complex terrain. The continuously observed turbulent statistical quantities, Lagrangian time scales, mesoscale flow field, and mixing layer depth in the PBL in the Dianchi area in China are directly put into the model, and the diurnal variations of air pollution are forecasted, which are dominated by such mesoscale local circulations as mountain and valley breeze, land and lake breeze, and city heat island (Kunming City). The results show that in the case of inputting the same data, they are in good agreement with the experimental data, as well as with the results of the three-dimensional advection-diffusion model (TD-ADM); the diurnal variation of mesoscale local circulation results in the obvious diurnal variation of mesoscale concentration distribution patterns; the Dianchi lake (appr. 300 km2) has a considerable effect on the distribution of air pollution in the area. 相似文献
14.
Atmospheric modeling is considered an important tool with several applications such as prediction of air pollution levels, air quality management, and environmental impact assessment studies. Therefore, evaluation studies must be continuously made, in order to improve the accuracy and the approaches of the air quality models. In the present work, an attempt is made to examine the air pollution model (TAPM) efficiency in simulating the surface meteorology, as well as the SO2 concentrations in a mountainous complex terrain industrial area. Three configurations under different circumstances, firstly with default datasets, secondly with data assimilation, and thirdly with updated land use, ran in order to investigate the surface meteorology for a 3-year period (2009–2011) and one configuration applied to predict SO2 concentration levels for the year of 2011.The modeled hourly averaged meteorological and SO2 concentration values were statistically compared with those from five monitoring stations across the domain to evaluate the model’s performance. Statistical measures showed that the surface temperature and relative humidity are predicted well in all three simulations, with index of agreement (IOA) higher than 0.94 and 0.70 correspondingly, in all monitoring sites, while an overprediction of extreme low temperature values is noted, with mountain altitudes to have an important role. However, the results also showed that the model’s performance is related to the configuration regarding the wind. TAPM default dataset predicted better the wind variables in the center of the simulation than in the boundaries, while improvement in the boundary horizontal winds implied the performance of TAPM with updated land use. TAPM assimilation predicted the wind variables fairly good in the whole domain with IOA higher than 0.83 for the wind speed and higher than 0.85 for the horizontal wind components. Finally, the SO2 concentrations were assessed by the model with IOA varied from 0.37 to 0.57, mostly dependent on the grid/monitoring station of the simulated domain. The present study can be used, with relevant adaptations, as a user guideline for future conducting simulations in mountainous complex terrain. 相似文献
15.
Using the new high-frequency measurement equipment of the research aircraft DO 128, which is described in detail, turbulent vertical fluxes of ozone and nitric oxide have been calculated from data sampled during the ESCOMPTE program in the south of France. Based on airborne turbulence measurements, radiosonde data and surface energy balance measurements, the convective boundary layer (CBL) is examined under two different aspects. The analysis covers boundary-layer convection with respect to (i) the control of CBL depth by surface heating and synoptic scale influences, and (ii) the structure of convective plumes and their vertical transport of ozone and nitric oxides. The orographic structure of the terrain causes significant differences between planetary boundary layer (PBL) heights, which are found to exceed those of terrain height variations on average. A comparison of boundary-layer flux profiles as well as mean quantities over flat and complex terrain and also under different pollution situations and weather conditions shows relationships between vertical gradients and corresponding turbulent fluxes. Generally, NOx transports are directed upward independent of the terrain, since primary emission sources are located near the ground. For ozone, negative fluxes are common in the lower CBL in accordance with the deposition of O3 at the surface.The detailed structure of thermals, which largely carry out vertical transports in the boundary layer, are examined with a conditional sampling technique. Updrafts mostly contain warm, moist and NOx loaded air, while the ozone transport by thermals alternates with the background ozone gradient. Evidence for handover processes of trace gases to the free atmosphere can be found in the case of existing gradients across the boundary-layer top. An analysis of the size of eddies suggests the possibility of some influence of the heterogeneous terrain in mountainous area on the length scales of eddies. 相似文献
16.
China has been experiencing widespread air pollution due to rapid industrialization and urbanization in recent decades.The two major concerns of ambient air quality in China are particulate matter(PM) and tropospheric ozone(O_3). With the implementation of air pollution prevention and control actions in the last five years, the PM pollution in China has been substantially reduced. In contrast, under the conditions of the urban air pollution complex, the elevated O_3 levels in city clusters of eastern China, especially in warm seasons, have drawn increasing attention. Emissions of air pollutants and their precursors not only contribute to regional air quality, but also alter climate. Climate change in turn can change chemical processes, long-range transport, and local meteorology that influence air pollution. Compared to PM, less is known about O_3 pollution and its climate effects over China. Here, we present a review of the main findings from the literature over the period 2011–18 with regard to the characteristics of O_3 concentrations in China and the mechanisms that drive its interannual to decadal variations, aiming to identify robust conclusions that may guide decision-making for emissions control and to highlight critical knowledge gaps. We also review regional and global modeling studies that have investigated the impacts of tropospheric O_3 on climate, as well as the projections of future tropospheric O_3 owing to climate and/or emission changes. 相似文献
17.
Li Mengmeng Wang Tijian Xie Min Zhuang Bingliang Li Shu Han Yong Cheng Nianliang 《Theoretical and Applied Climatology》2017,128(3-4):999-1013
Through regulating the land–atmosphere energy balance, urbanization plays an important role in modifying local circulations and cross-border transport of air pollutants. The Beijing–Tianjin–Hebei (BTH) metropolitan area in northern China is frequently influenced by complex atmospheric thermal circulations due to its special topography and geographic position. In this study, the Weather Research and Forecasting (WRF) model combined with remote sensing is used to explore the urbanization impacts on local circulations in the BTH region. The urban heat island (UHI) effect generated around Beijing and Tianjin shows complex interactions with local thermal circulations. Due to the combined effects of UHI and topography, the UHI circulation around Beijing and valley breeze at the southern slopes of Yan Mountain are coupled together to reinforce each other. At the coastal cities, the increased land/sea temperature gradient considerably accelerates the sea breeze along Bohai Bay and moves the sea breeze front further inland to reach as far as Beijing. This study may lay a foundation for the better understanding of air pollutant dispersion on complex terrain.
相似文献18.
S. A. Penkett K. C. Clemitshaw N. H. Savage R. A. Burgess L. M. Cardenas L. J. Carpenter G. G. McFadyen J. N. Cape 《Journal of Atmospheric Chemistry》1999,33(2):111-128
Detailed studies have been made of the behaviour of gases and radicals involved in the production of oxidants at the Weybourne Atmospheric Observatory in both summertime and wintertime conditions. In June 1995 the range of meteorological conditions experienced varied such that ozone destruction was observed in clean northerly air flows reaching Weybourne down the North Sea from the Arctic, and ozone production was observed in varying degrees in air with different loadings of nitrogen oxides and other precursors. The transition point for ozone destruction to ozone production occurred at a nitric oxide concentration of the order of 50 pptv. Plumes of polluted air from various urban areas in the U.K. were experienced in the June campaign at Weybourne. Quantitative studies of ozone production in a plume from the Birmingham conurbation on 18 June 1995 showed that the measurement of ozone production agreed well with calculated production rates from the product of the nitric oxide and peroxy radical concentrations (r2=0.9). In wintertime conditions (October–November 1994) evidence was also found for oxidant production, defined as the sum of O3+NO2. At this time of year the peroxy radical concentrations (RO2) were much lower than observed in the summertime and the nitric oxide (NO) was much higher. There was still sufficient RO2 during the day, however, for a slow accumulation of oxidant. Confirmatory evidence for this comes from the diurnal co-variance of (O3+NO2) with PAN, an excellent tracer of tropospheric photochemistry. The same type of covariance occurs in summer between PAN and ozone. The results obtained in these series of measurements are pertinent to understanding the measures necessary to control production of regional photochemical air pollution, and to the production of ozone throughout the northern hemisphere in winter. 相似文献
19.
The Role of Planetary Boundary-Layer Parameterizations in the Air Quality of an Urban Area with Complex Topography 总被引：3，自引：1，他引：2
Elizabeth Bossioli Maria Tombrou Aggeliki Dandou Eleni Athanasopoulou Kostas V. Varotsos 《Boundary-Layer Meteorology》2009,131(1):53-72
The effect of different planetary boundary-layer (PBL) parameterization schemes on the spatial distribution of atmospheric
pollution over the complex topography of the greater Athens area is investigated. Four PBL schemes originally implemented
in a numerical meteorological model and a fifth one simulating the urban effect are examined. Two different atmospheric conditions
are analyzed; a typical summer and a typical winter pollution episode. The relative importance of chemical and physical processes
of the pollution predictions is discussed using process analysis. It is revealed that, for primary pollutants, a local scheme
seems more adequate to represent the maximum observed concentrations while, completely different in structure, a non-local
scheme reproduces the mean observed values in the basin. Concerning secondary pollutants, peak concentration differences,
due to the different PBL schemes, are smoothed out. Nevertheless, the PBL scheme selection shapes the horizontal and the vertical
extension of maximum values. The non-local and semi non-local schemes are superior to the others, favouring strong vertical
mixing and transport towards the surface. The stronger turbulence accommodated effectively by the semi non-local urban scheme
enhances ozone production along the sea-breeze axis and preserves the high ozone concentrations during the nighttime hours
in the urban core. 相似文献
20.
城市不同下垫面与建筑物空间形态对近地表气温等微气候要素产生了重要影响。开展城市气温时空变化模拟与影响因素分析,对于城市热环境评价与城市规划具有重要意义。论文基于高空间分辨率Geoeye-1立体影像,在建筑物高度、下垫面覆盖类型信息提取的基础上,选择南京一中、光华东街、玄武湖、头陀岭4个区域,采用ENVI-met微气候模式,以城市基本气象站南京站的实时气象数据作为背景气象场,模拟不同区域近地表气温的时空分布特征,并利用区域自动气象站观测数据进行精度检验。结果表明:在时间变化上,ENVI-met模拟气温与实测值之间吻合程度较高;在空间分布上,南京一中与光华东街区域气温时空分布规律总体相似,但城市空间形态的差异使得局部区域气温变化不同,玄武湖区域气温由陆地中心向外围呈递减趋势,而头陀岭地形复杂多变,白天气温变化剧烈,夜间空间变化较小。 相似文献