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1.
城市中水体布局对大气环境的影响 总被引：2，自引：0，他引：2
城市下垫面状况在很大程度上决定城市大气物理环境的特征。在城市区域增加湿地等自然地表有利于城市的减温增湿,促使局地流场发生变化,改善局地微气象条件以及大气物理环境。城市规划大气物理环境多尺度数值模拟系统为城市规划大气物理环境定量评估提供了有效的模拟工具。利用该系统中的城市尺度模式模拟了水体布局为集中型和分散型,水体面积占有率分别为4%、8%、12%和16%条件下,城市大气温度、湿度、风速、城市大气扩散条件的变化及其对城市大气环境的影响,利用北京市城市水体气象观测数据,分析了水体周边和商业区、交通区温、湿度的差异,并对模式模拟结果进行了验证,揭示了城市水体布局对城市大气物理环境影响的可能机制。模拟和观测结果显示,城市水体布局会对城市微气象环境产生一定影响。无论分散型或集中型布局,城市水体面积的增加,都在一定程度上使城市气温降低、湿度增加、平均风速增大。比较而言,分散型水体布局对城市区域微气象环境的影响更为显著。 相似文献
2.
An urban boundary layer model (UBLM) is improved by
incorporating the effect of buildings with a sectional drag coefficient and
a height-distributed canopy drag length scale. The improved UBLM is applied
to simulate the wind fields over three typical urban blocks over the Beijing
area with different height-to-width ratios. For comparisons, the wind fields
over the same blocks are simulated by an urban sub-domain scale model
resolving the buildings explicitly. The wind fields simulated from the two
different methods are in good agreement. Then, two-dimensional building
morphological characteristics and urban canopy parameters for Beijing are
derived from detailed building height data. Finally, experiements are
conducted to investigate the effect of buildings on the wind field in
Beijing using the improved UBLM. 相似文献
3.
Impact Assessment of Urban Meteorology and the Atmospheric Environment Using Urban Sub-Domain Planning 总被引：3，自引：0，他引：3
For the purpose of (1) investigating the relationship between urban planning and the atmospheric environment, and (2) improving
the atmospheric environment through rational and scientific planning, an urban sub-domain scale model is developed in the
form of a three-dimensional non-hydrostatic model with k – ɛ closure. The distribution and azimuth of buildings, the screening of shortwave radiation by buildings, and the underlying
surface type as characteristics of the urban environment are included, the ground temperature is calculated using the force-restore
method, and the concentration equation is solved simultaneously. The model is evaluated using special field observations and
wind-tunnel experiment data, showing that model results meet the observational and experimental data generally well. Based
on the model, an index system and evaluation method is set up to assess the impact of urban meteorology and the atmospheric
environment using urban sub-domain planning. As an example, two layouts of a specific sub-domain in Beijing are assessed.
The impact assessment system of urban meteorology and the atmospheric environment using urban sub-domain planning, which includes
the urban sub-domain scale numerical model, index system and evaluation method, provides an effective approach to improve
the atmospheric environment through rational and scientific planning. 相似文献
4.
随着沿海城市的快速发展,城市气候环境恶化,研究弱大气环流背景下的海陆风对改善城市环境具有重要意义。以晋江市为例,利用站点风要素观测数据,结合海陆风判别条件,提取并分析了两个典型海陆风日海陆风的基本特征;采用WRF与Noah陆面过程模式耦合,选用BEP多层城市冠层模型,对典型日进行了风场模拟。从模拟结果中分解出局地风,在验证海陆风现象的基础上,分析了海陆风特征的空间分布规律。结果显示:WRF模拟的逐小时局地风向时序与实测情况吻合较好,通过了信度为0.05的显著性检验,但局地风速模拟值与实测值存在显著差异,平均达到1 m/s。从WRF模拟结果提取的海、陆风起始和终止时间、持续时间与实际情况存在一定差别。两者持续时间在空间上的变化与各自起始时间的空间变化一致,且未明显出现随离岸距离增加,海陆风减弱的现象。上述结果表明,WRF能够较好地模拟海陆风日的风场特征,尽管对海、陆风速的模拟还存在一定的不确定性,但所得结论对晋江市城市规划和微环境改善有参考意义。 相似文献
5.
An Application of the RAMS/FLUENT System on the Multi-Scale Numerical Simulation of the Urban Surface Layer A Preliminary Study 总被引：1，自引：0，他引：1
The Regional Atmospheric Modeling System （RAMS） and the computational fluid dynamics （CFD） codes known as FLUENT are combinatorially applied in a multi-scale numerical simulation of the urban surface layer （USL）. RAMS and FLUENT are combined as a multi-scale numerical modeling system, in which the RAMS simulated data are delivered to the computational model for FLUENT simulation in an offline way. Numerical simulations are performed to present and preliminarily validate the capability of the multi-scale modeling system, and the results show that the modeling system can reasonably provide information on the meteorological elements in an urban area from the urban scale to the city-block scale, especially the details of the turbulent flows within the USL. 相似文献
6.
气象高性能计算应用服务环境适应性研究 总被引：6，自引：1，他引：5
为满足气象数值模式业务系统对高性能计算应用服务环境不断增长的需求,提供数值模式稳定、高效运行的应用平台,开展了气象高性能计算应用服务环境建设工作。对应用需求进行了深入分析,规划设计并初步实施了建设方案,主要包括系统与应用流程统一规划、模式软件应用框架构建等内容。为气象数值模式业务及科研工作的开展提供了有力的技术支撑和保障。 相似文献
7.
城市环境气候图最初于20世纪70年代由德国气候研究者开发制作,通过近40年的发展,目前在世界范围内已有20个国家开展了相关研究与应用项目,从而为改善城市气候环境与提高人居生活条件提供决策依据。该文首先对城市环境气候图的发展及其制作方法进行了一个总体性的回顾,然后选取德国、日本和中国香港地区的研究案例用以考察目前该领域研究和应用现状与存在问题,进一步详细探讨了未来发展的方向,最后指出了在我国城市化进程中为应对诸多气候环境问题所迫切需要开展的相关研究问题。 相似文献
8.
开展城市建筑物方位、高度等建筑布局要素对局地热环境时空变化的影响研究,对于合理的城市规划布局具有重要理论意义与实践参考价值。采用ENVI-met 微气候模式,在南京江北新区顶山街道某区域微气候模拟的基础上,选择一个二类居住用地并设计不同的建筑布局要素作为规划场景,模拟分析了建筑物高度与建筑间距之比（H/W）、建筑布局变化对区域热环境的影响。结果表明:ENVI-met 能够以较高精度模拟2 m高度气温;H/W与建筑布局形式都会影响区域热环境,适当增加H/W可在一定程度上降低夏季气温,H/W为1.4时的热环境更为舒适,而不同建筑布局形式下的不同区域温度差异较大。 相似文献
9.
10.
城市洪灾的成因是多方面的，除受地理地形、气候条件等许多自然因素影响外，也受到人类活动等人为因素影响。城市不透水地面增多，城区降水增多及绿地、植被减少，排洪能力差，水体面积减少等，是城市内涝加剧的主要原因。为减轻和预防洪水给城市居民带来生命和财产威胁，应做好防洪规划。在做规划时，除应考虑提高防洪标准、加快建设城市防洪工程并保证其质量、增加地面覆盖度、改善生态环境、妥善管理防洪设施外，还应考虑风险与脆弱性、减少地面沉降及建立现代化防洪体系。 相似文献
11.
嵌套网格空气质量预报模式系统的发展与应用 总被引：74，自引：4，他引：74
主要综述中国科学院大气物理研究所自主开发的嵌套网格空气质量预报模式系统(NAQPMS,Nested Air Quality Prediction Modeling System)的历史发展与应用情况.模式发展伊始为欧拉污染物输送实用模型,利用其研究东亚硫氧化物的跨国输送问题,得出中国对于周边国家的输送量不大的结论; 在系统中嵌入适合东亚的起沙机制模块,用来模拟沙尘发生、输送及沉降等过程,估算亚洲大陆沙尘气溶胶对海洋地区的输送与沉降通量,为研究海洋生物地球化学循环提供基础数据; 利用该系统研究沙尘及其土壤粒子对酸雨的中和作用,发现沙尘输送对东亚酸雨的分布影响很大; 发展城市尺度高分辨率气象和空气质量预报技术,使模式水平分辨率达到500 m,并应用于台北高浓度臭氧和PM10的模拟; 研究和集成区域及城市尺度大气污染预报理论和模拟技术,研制成目前的嵌套网格空气质量预报模式系统,以探讨不同尺度各种污染(如沙尘暴、城市光化学烟雾、酸雨、高浓度悬浮颗粒物等)的变化规律.在模式系统中初步建立资料同化模块,开展大气化学成分及沙尘输送模拟的资料同化研究.系统已经在北京、上海、深圳、郑州等城市环境监测中心实施空气质量的实时预报.未来,系统将集成到全球环境大气输送模式(GEATM),以实现从城市群到全球具有双向耦合功能的模式系统. 相似文献
12.
城市气象研究进展 总被引：5，自引：0，他引：5
中国数十年来在城市气象研究这一新兴学科领域开展了大量研究并获得了多方面的丰硕成果。文中从城市气象观测网与观测试验、城市气象多尺度模式、城市气象与大气环境相互影响、城市化对天气气候的影响等4个方面论述了城市气象的主要研究进展:中国各大城市已建立或正在完善具有多平台、多变量、多尺度、多重链接、多功能等特点的城市气象综合观测网;北京、南京、上海等地开展了大型城市气象观测科学试验,被世界气象组织列入研究示范项目;成功开展了风洞实验、缩尺度外场实验研究;建立了多尺度城市气象和空气质量预报数值模式,并应用于业务;在城市热岛效应、城市对降水影响、城市气象与城市规划、城市化对区域气候及空气质量的影响、城市气象与大气环境相互作用等研究领域取得长足进展。最后指出,未来需要重点从新观测技术及观测资料同化应用、城市系统模式研究、城市化对天气气候的影响机理、城市化对大气环境和人体健康的影响、城市水文气象气候与环境综合服务等方面开展科学研究与应用,为中国城市化、生态文明建设、防灾减灾和应对气候变化等国家需求提供科技支撑。 相似文献
13.
A microscale model for air pollutant dispersion simulation in urban areas: Presentation of the model and performance over a single building 总被引：1，自引：0，他引：1
A microscale air pollutant dispersion model system is developed for emergency response purposes. The model includes a diagnostic wind field model to simulate the wind field and a random-walk air pollutant dispersion model to simulate the pollutant concentration through consideration of the influence of urban buildings. Numerical experiments are designed to evaluate the model's performance, using CEDVAL(Compilation of Experimental Data for Validation of Microscale Dispersion Models) wind tunnel experiment data, including wind fields and air pollutant dispersion around a single building. The results show that the wind model can reproduce the vortexes triggered by urban buildings and the dispersion model simulates the pollutant concentration around buildings well. Typically, the simulation errors come from the determination of the key zones around a building or building cluster. This model has the potential for multiple applications; for example, the prediction of air pollutant dispersion and the evaluation of environmental impacts in emergency situations; urban planning scenarios;and the assessment of microscale air quality in urban areas. 相似文献
14.
Study on Effects of Building Morphology on Urban Boundary Layer Using an Urban Canopy Model 
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下载免费PDF全文 An urban canopy model is incorporated into the Nanjing University Regional Boundary Layer Model. Temperature simulated by the urban canopy model is in better agreement with the observation, especially in the night time, than that simulated by the traditional slab model. The coupled model is used to study the effects of building morphology on urban boundary layer and meteorological environment by changing urban area, building height, and building density.It is found that when the urban area is expanded, the urban boundary layer heat flux, thermal turbulence, and the turbulent momentum flux and kinetic energy all increase or enhance, causing the surface air temperature to rise up. The stability of urban atmospheric stratification is affected to different extent at different times of the day.When the building height goes up, the aerodynamic roughness height, zero plane displacement height of urban area, and ratio of building height to street width all increase. Therefore, the increase in building height results in the decrease of the surface heat flux, urban surface temperature, mean wind speed, and turbulent kinetic energy in daytime. While at night, as more heat storage is released by higher buildings, thermal turbulence is more active and surface heat flux increases, leading to a higher urban temperature.As the building density increases, the aerodynamic roughness height of urban area decreases, and the effect of urban canopy on radiation strengthens. The increase of building density results in the decrease in urban surface heat flux, momentum flux, and air temperature, the increase in mean wind speed, and the weakening of turbulence in the daytime. While at night, the urban temperature increases due to the release of more heat storage. 相似文献
15.
良好的气象探测环境,才能获取优质的气象探测信息。近几十年来,城市化带来的城市建筑面积猛增和城市建设用地增加,致使气象探测环境频频遭受破坏,严重影响了气象探测资料的准确性、代表性和比较性,必须引起高度重视。简述了气象探测环境保护要求的历史沿革和法律依据。以实例分析了气象探测环境保护面临的严峻形势。统计得出气象探测环境遭破坏主要由于周围建筑物超过《气象探测环境和设施保护办法》限制的高度,其原因来自于气象部门外部和内部两个方面,国家经济社会快速发展和当地政府的土地开发利益使得房地产建设迅猛发展,不可遏制;气象部门内部的办公、业务用房建设标准以及气象观测站新站址选择模式,使得选址困难和频繁被迁站。有针对性地提出保护气象探测环境也应从气象部门内部和外部两个方面入手,气象部门内部需要确立气象探测环境保护标准的科学性、严谨性,建立气象探测环境的分类保护机制;依法保护气象探测环境的同时充分应用行政干预;顺应国家经济社会的发展形势,周全应对气象探测环境保护问题;对被迫搬迁的气象观测站,选择新址时应将探测环境保护需求放在首位;同时新站址的建设布局可以采用多种模式。 相似文献
16.
D. Pavlidis G. J. Gorman J. L. M. A. Gomes C. C. Pain H. ApSimon 《Boundary-Layer Meteorology》2010,136(2):285-299
The computational fluid dynamics code Fluidity, with anisotropic mesh adaptivity, is used as a multi-scale obstacle-accommodating
meteorological model. A novel method for generating realistic inlet boundary conditions based on the view of turbulence as
a superposition of synthetic eddies is adopted. It is able to reproduce prescribed first-order and second-order one-point
statistics and turbulence length scales. The aim is to simulate an urban boundary layer. The model is validated against two
standard benchmark tests: a plane channel flow numerical simulation and a flow past a cube physical simulation. The performed
large-eddy simulations are in good agreement with both reference models giving confidence that the model can be used to successfully
simulate urban atmospheric flows. 相似文献
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18.
基于呼和浩特市近50年逐日定时地面气象资料、2002—2006年的逐日07时和19时各标准层探空资料、2001—2006年逐日主要污染物浓度和主要污染源源强、1961—2006年社会经济数据、2002年城区建设现状及1996—2010年城市总体规划资料,利用区域边界层模式模拟方法,研究了呼和浩特市城区建设发展对大气环境的影响。结果表明：（1）呼和浩特市城区发展后（规划后）气温高于现状（规划前）,城区中心气温与周边地区气温差增大,城市热岛效应增强;（2）呼和浩特城区规划后冬季气流汇集辐合区域增多,辐合能力增强,从而使冬季大气污染加剧;（3）呼和浩特市城区扩展后引起的下垫面热力与动力参数变化,将导致气流场发生显著变化,使得污染物的辐合能力增强。总体而言,呼和浩特市城区规划后虽增加了部分绿地等面积,但建筑物的增高增密、下垫面性质的改变,将使大气环境扩散能力减弱,大气污染加重。 相似文献
19.
Simulation of Meteorological Fields Within and Above Urban and Rural Canopies with a Mesoscale Model 总被引：3，自引：4，他引：3
Accurate simulation of air quality at neighbourhood scales (on order of 1-km horizontal grid spacing) requires detailed meteorological fields inside the roughness sub-layer (RSL). Since the assumptions of the roughness approach, used by most of the mesoscale models, are unsatisfactory at this scale, a detailed urban and rural canopy parameterisation, called DA-SM2-U, is developed inside the Penn State/NCAR Mesoscale Model (MM5) to simulate the meteorological fields within and above the urban and rural canopies. DA-SM2-U uses the drag-force approach to represent the dynamic and turbulent effects of the buildings and vegetation, and a modified version of the soil model SM2-U, called SM2-U(3D), to represent the thermodynamic effects of the canopy elements. The turbulence length scale is also modified inside the canopies. SM2-U(3D) assesses the sensible and latent heat fluxes from rural and urban surfaces in each of the computational layers inside the canopies by considering the shadowing effect, the radiative trapping by the street canyons, and the storage heat flux by the artificial surfaces. DA-SM2-U is tested during one simulated day above the city of Philadelphia, U.S.A. It is shown that DA-SM2-U is capable of simulating the important features observed in the urban and rural RSL, as seen in the vertical profiles of the shear stress, turbulent kinetic energy budget components, eddy diffusivity, potential air temperature, and specific humidity. Within the canopies, DA-SM2-U simulates the decrease of the wind speed inside the dense canopies, the skirting of the flow around the canopy blocks, warmer air inside the vegetation canopy than above open areas during the night and conversely during the day, and constantly warmer air inside the urban canopy. The comparison with measurements shows that the surface air temperature above rural and urban areas is better simulated by DA-SM2-U than by the `standard version' of MM5. 相似文献
20.
选取鄂尔多斯市东胜区为代表区域。基于该区域1961-2006年定时地面气象观测资料,2002-2006年08时、20时各标准层探空以及2001-2006年主要污染源源强、1961-2006年社会经济数据、2002年卫星遥感反演资料、2003-2020年城市总体规划资料等,利用区域边界层模式模拟方法,分析鄂尔多斯市城市化进程对局地大气环境的影响。结果表明:东胜区发展后(2020年)气温低于现状(2002),使城区中心气温与周边地区气温差异变小,对城区大气环境的改善较为有利。东胜城区扩展后,在污染严重的冬季,气流辐合区域减少,辐散能力增强,对减轻城区污染和改善大气环境有利。城区拓展后由于下垫面等布局发生变化, 气流场变化较大,但从污染物的扩散能力来看,按规划发展后城区污染轻于现状。 相似文献