北京奥运交通限行前后街道机动车污染的模拟  

Modeling the Vehicle Pollution in the Urban Streets Before and During the Beijing Olympic Games Traffic Control Period

作　　者：汪婷[1] 谢绍东[1] 

机构地区：[1]北京大学环境科学与工程学院,环境模拟与污染控制国家重点实验室,北京100871

出　　处：《环境科学》2010年第3期566-572,共7页Environmental Science

基　　金：中意合作北京市智能交通-交通污染监控示范项目(ITS-TAP);美国能源基金会支持项目;环保公益项目(200709001)

摘　　要：为评估北京市街道的机动车污染状况及奥运期间的改善程度,利用OSPM模型模拟计算了2008年7月奥运交通限行前后北京街道大气中PM10、CO、NO2和O3的浓度,得到其在限行前的日均浓度值分别为146μg/m3、3.83 mg/m3、114.4μg/m3和4.71×10-9,限行后为112μg/m3、3.16 mg/m3、102.4μg/m3和5.31×10-9,削减率分别是23.4%、20.5%、10.5%和-12.5%.对污染物在限行前后的浓度变化和日变化趋势的研究发现,PM10浓度受交通限行影响削减最大;CO浓度的日变化趋势与机动车流量的变化最为类似;NO2在限行后的削减幅度有限,表明其浓度还受到除交通排放外的其他因素影响;O3浓度在限行期间有所上升,说明限行措施不能降低街道中大气O3浓度.另外,比较不同类型街道的计算结果,发现街道车型构成与几何形状对污染物浓度变化有影响.总之,北京市在实施交通管制前,街道中PM10、CO和NO2的日均浓度均接近或超过国家空气质量二级标准限值,机动车污染状况较为严重;交通限行可有效降低一次污染物的浓度,但二次污染物的浓度有可能升高.In order to investigate the vehicle pollution situation in the streets in Beijing and the abatement during the Olympic Games,the OSPM model was applied to calculate the concentrations of PM10,CO,NO2 and O3 inside the urban streets of Beijing before and during the Olympic traffic controlling period in July, 2008.The modeled concentrations before the traffic control are 146 μg/m^3,3.83 mg/m^3,114.4 μg/m^3 and 4.71×10^-9,while after the traffic control are 112 μg/m^3,3.16 mg/m^3,102.4 μg/m^3 and 5.31×10^-9,with the reduction rates of 23.4%,20.5%,10.5% and-12.5%,respectively.The research on these concentration changes and the daily variations of the pollutants reveals： the concentration of PM10 is most influenced by the traffic control;the concentration of CO presents the most similar daily variation with the traffic flow;the reduction of NO2 concentration is limited,indicating the influence of other factors other than the traffic emission;the concentration of O3 increases after the traffic control,which means the traffic management measures can not abate the O3 pollution in the street.Furthermore,the comparison between the calculation results in different types of street canyons reveals that the fleet composition and street geometry impact the concentration changes.In a word,the vehicle pollution inside the streets of Beijing before the traffic control is relatively serious,as the concentrations of PM10,CO and NO2,all approach or exceed the Grade Ⅱ National Air Quality Standard;the traffic control measures take effect in reducing the primary pollutants,but the secondary pollutants may increase after the traffic control.

关 键 词：机动车污染 街道峡谷 北京奥运 OSPM模型 

分 类 号：X823[环境科学与工程—环境工程] X820.6