中文摘要：

利用2008年7～9月北京污染监测资料、气象观测资料、韩国气象厅天气图资料及NCEP再分析资料,分析了2008年奥运会期间北京地区空气动力学当量直径小于等于10μm颗粒物（PM10）污染特征及其成因,统计了利于和不利于污染物扩散的天气形势,研究了北京发生PM10污染的典型天气形势和气象条件。结果表明：1）奥运会期间北京共有8天出现PM10污染,包括一次持续污染过程,奥运会赛时和残奥会赛时未出现污染过程,这主要与北京8、9月降水偏多有关;2）不利于污染扩散的天气形势（如风速较小、偏南风、高温高湿、近地层出现持续逆温）出现频率较高,但并未造成特征性的PM10污染,这可能与奥运会期间的污染控制措施有关;3）PM10污染过程多与台风系统或热带低压的北上,从而阻滞了华北地区天气系统的南下东移相关联。

英文摘要：

Using the air pollution and meteorological data in Beijing,weather charts from Korea Meteorological Administration（KMA） and NCEP reanalysis data,the characteristics of the air pollution of Particulate Matter with particle size below 10 μm（PM10） in Beijing and its cause of formation during the 2008 Olympic Games period（from July to September） are analyzed,types of synoptic situations are classified according to being or not helpful to dispersion of pollutants,and typical synoptic situations and meteorological conditions in PM10 air pollution episodes are studied.The results are that：1） There were eight days with PM10 air pollution in Beijing during the whole period,including a persistent PM10 air pollution.But no PM10 air pollution occurred during the Olympic Games and Paralympic Games,which mainly resulted from more rainfall in August and September of 2008.2） Synoptic situations not helpful to pollutants dispersion（e.g.south wind with low speed,high air temperature and relative humidity,and persistent vertical inversion in low layer） were frequent,but they did not cause typical PM10 air pollution by a possible reason of the pollution control measures.3） Most PM10 air pollutions were related with northwestward-moving typhoon or tropical cyclone,which would block synoptic system influencing North China to move eastward.