中文摘要：

2012年6月9-14日长江中下游地区发生了一次由夏季的秸秆焚烧引发的比较严重的区域性大气污染事件。污染持续期间,区域内4个典型城市（徐州、南京、合肥、武汉）污染变化过程有显著差异。该文首先通过应用卫星火点数据对污染源的逐日变化进行分析,同时利用城市空气监测数据（API）、城市天气数据和NCEP再分析资料,对各城市的污染过程（发生时间、持续过程,污染指数变化趋势）进行对比分析,并运用Hysplit-4模式反演污染事件中各城市污染物的扩散轨迹。结果表明：城市的地理、天气条件对城市受污染程度均有不同程度的影响,其中以气候因素为首要影响因素,表明城市环境容量的降低使得城市对污染的敏感度增加。针对现状,提出城市与区域大气污染进行防控的建议。

英文摘要：

In the period of June 9 to June 14,2012,a serious regional air pollution event took place over the middle and lower reaches of Yangtze River. During the air pollution,there are significant differences in the pollution process of the four typical cities including Xuzhou,Nanjing,Hefei and Wuhan. The daily fire-point number derived from satellite data was examined firstly. Then urban historical weather data,air pollution index and NCEP reanalysis data were used for contrastive analysis of the pollution process of the four typical cities and furthermore the diffused track of pollutants that influences the cities was retrieved by the Hysplit-4 mode. The results illustrated that the city pollution level is affected by geography and weather conditions and the influence of the climate factors are primary influencing factors. It indicates that the reducing of urban environmental capacity leads to the increasing sensitivity of the city to pollution. Some proposals in prevention and control of urban and regional air pollution are put forward as well.