北京城区夏季污染建立、维持、消退的天气过程  

The Developing, Maintaining, and Diminishing Process of Summertime Pollution in Urban Area of Beijing

作　　者：赵文灿 胡开明[3,4] 黄刚[2,3] 陈元昭 ZHAO Wencan HU Kaiming HUANG Gang and CHEN Yuanzhao(College of Atmospheric Sciences, Plateau Atmosphere and Environment Key Laboratory of Sichuan Province, Chengdu University of Information Technology, Chengdu 610225 2 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029 3 Joint Center for Global Change Studies, Beijing 100875 4 Center for Monsoon System Research, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100190 5 Shenzhen Municipal Meteorological Bureau, Shenzhen 518040)

机构地区：[1]成都信息工程大学四川省高原大气和环境重点实验室/大气科学学院,成都610225 [2]中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室,北京100029 [3]全球变化研究协同创新中心,北京100875 [4]中国科学院大气物理研究所季风系统研究中心,北京100190 [5]深圳市气象台,深圳518040

出　　处：《气候与环境研究》2016年第4期479-489,共11页Climatic and Environmental Research

基　　金：国家重点基础研究发展计划项目2012CB955604;深圳市气象局南方强天气研究重点实验室项目SZQX2015173;国家自然科学基金41425019;91337105;41275083~~

摘　　要：利用北京城区污染观测站2006~2013年夏季可吸入颗粒物PM10逐日浓度检测资料,挑选所有PM10浓度大于150μg/m^3的个例,合成分析华北及北京地区风场变化情况,发现风速在污染当天变化不明显,南风与PM10的相关性普遍为正,污染当天各区南风增加较大,太行山一带甚至增长了5倍。南风异常可能会使河北、山东等地污染物向北京输送,造成北京大气污染。同时我们分析北京夏季空气污染时大气环流特征。在500 h Pa与200 h Pa,北京和内蒙古上空有显著的高压异常。在850 h Pa,环流场表现为东正西负的高度场异常,其中北京在正负异常分界线上。低层气压梯度异常会造成北京和以南地区南风异常。同时,我们发现北京污染天气伴随的高空环流异常具有准定常特征。在污染前4天,蒙古上空存在一个显著的高层高压异常。该高压异常增强并向南延伸,在污染当天控制北京和内蒙古。在污染消退期,该异常也逐渐消退。但在消退后第四天,北京和内蒙古上空依然受高压异常控制。这表明北京夏季污染和高空准定常环流异常有关。All the summer air pollution cases in Beijing during the period of 2006 to 2013 are identified based on daily PM10 concentration data collected at stations in urban area of Beijing. A pollution case is determined if daily mean maximum PM10 concentration satisfies the criterion PM10 concentration 〉 150 μg/m3. The corresponding atmospheric circulation patterns are then analyzed. It is found that the PM10 concentration in Beijing is significantly correlated with southerly winds in the surrounding regions of Beijing. When PM 10 concentration is high in Beijing, strong southerly wind anomalies tend to appear to the south of Beijing with the maximum southerly wind anomalies along the eastern flank of the Taihang Mountain. Since pollution emissions are large in some regions to the south of Beijing, southerly winds apparently are favorable for pollution transport from Hebei and Shandong to Beijing, resulting in air pollution in Beijing. During periods of air pollution, positive geopotential height anomalies occur in the middle and upper troposphere above Beijing and Inner Mongolia; in the lower troposphere, positive pressure anomalies occur in the east and negative anomalies occur in the west. Beijing is located in between the positive and negative pressure anomalies, where the surface pressure gradient anomalies lead to southerly wind anomalies in the regions surrounding Beijing. Furthermore, the positive geopotential height anomalies in the upper-level associated with air pollution in Beijing are quasi-stationary, indicating that summertime air pollution in Beijing is possibly associated with quasi-stationary circulation anomalies. Large positive geopotential height anomalies in the upper troposphere over the Mongolia often establish four days before the pollution occurrence. Such anomalies gradually extend southward and strengthen, and eventually control Beijing and Inner Mongolia on the pollution day. As the anomalous circulation pattern weakens, air pollution diminishes correspondingly. However, positive geopoten

关 键 词：风场输送 PM10浓度 合成分析 华北地区 高度场异常 

分 类 号：P401[天文地球—大气物理学与大气环境]