乌鲁木齐重污染日的天气分型和边界层结构特征研究  

Researches of Weather Pattern and Boundary Layer Structure Characteristic on Serious Air Pollution Days in Urumqi

作　　者：李霞[1,2] 杨静 麻军 王江 赵克明 任泉 赵勇[2] 

机构地区：[1]中国科学院大气物理研究所中层大气与全球环境探测实验室,北京100029 [2]中国气象局乌鲁木齐沙漠气象研究所,新疆乌鲁木齐820002 [3]新疆气象科技服务中心,新疆乌鲁木齐820002 [4]新疆气象台,新疆乌鲁木齐820002 [5]乌鲁木齐国家基本气象站,新疆乌鲁木齐820002

出　　处：《高原气象》2012年第5期1414-1423,共10页Plateau Meteorology

基　　金：新疆气象科学技术研究项目(C2008001);中国沙漠气象科学基金项目(IDM2008003;Sqj20080014));环保公益性行业科研专项(200909007);新疆自然科学基金项目(2011211A102)共同资助

摘　　要：利用2004年1月-2009年4月高空、地面气象观测资料和逐日空气污染指数,对乌鲁木齐空气污染≥Ⅳ级的重污染日持续时间特征、500hPa高空环流形势、地面气压场及相应的边界层结构特征进行了统计分析。结果表明,乌鲁木齐重污染过程发生1天和持续2,3和4天的比例分别是32.2%,23.3%,18.5%和11.0%;发生重污染时500hPa以纬向环流型居多,占重污染总日数的84.2%,经向环流型为15.8%。从地面气压场来看,高压后部型出现重污染的频率最高,达86.3%;高压底部型次之,为9.6%;高压前部型和南高北低型出现重污染的几率较小。乌鲁木齐冬季Ⅲ级污染日对应的温度、湿度及风等要素廓线的垂直结构与冬季平均状况几乎一致,而重污染出现时,边界层逆温较强、风速较低且低空伴随有较厚的偏东风或东南风气流;重污染日和雾的关系密切,伴随有雾或轻雾的频率高达81.3%;前一日20:00(北京时)上干下湿并伴有逆温的边界层结构极易导致空气质量恶化。Using the real time meteorological observational data and daily air pollution index（API） from January 2004 to April 2009,the statistics were performed with regard to temperal distribution,500 hPa circulation pattern,surface pressure pattern and corresponding boundary layer structure on serious air pollution days with daily API above Ⅳ level.The results show that the occurrence frequencies of serious air pollution lasting for one,two,three and four days are 32.2%,23.3%,18.5% and 11.0%,respectively.The proportion of 500 hPa zonal circulation is relatively high with value of 86.3%,but for the meridional circulation only below 9.6% on high air pollution days.According to the location of surface high pressure center（SHPC）,the occurrence frequency reaches 86.3% when Urumqi is in the rear of the SHPC,and then the frequency of 9.6% is for the location at the bottom of the SHPC.The frequencies of the other two patterns are relatively low.The vertical structures of the average profiles such as temperature,relatively humidity and wind of grade Ⅲ air quality days are almost in agreement with that of average profiles in winter.Furthermore,the strong temperature inversion,lower wind speed and relatively deep easterly or southeasterly flows make great contributions to formation of serious air pollution.The relationship between serious air pollution and fog is significant with the fog occurrence frequency of 81.3%.Moreover,the air quality tends to be poor under conditions of the vertical structure with wet at low level but dry at upper level and inversion at 20：00（Beijing time） on the day before that day.

关 键 词：重污染日 环流形势 地面气压场 边界层结构 大气廓线 

分 类 号：X16[环境科学与工程—环境科学]