中文摘要：

本文利用卫星监测评估了2015年世界锦标赛和阅兵期间北京及周边地区空气质量变化。同时评估了活动期间实施的减排计划对空气污染物（NO2，SO2和气溶胶）产生的影响。研究结果显示与前三年（2012-2014年）同期卫星观测结果相比，北京及周边地区在活动期间NO2和SO2等其他空气污染物明显更低。同时研究也发现在活动期间，弱冷气团作用下的环流条佯有利手北京空气污染物的去除。

英文摘要：

Based on satellite observations, the effects of emission reduction measures on air pollutants （NO2 （nitrogen dioxide）, SO2 （sulfur dioxide）, and aerosols） were estimated in Beijing and its surroundings during the 2015 World Championships and Parade （WCP） held in Beijing. Compared with the same period in the previous three years （2012-2014）, the tropospheric vertical column densities of NO2 and SO2 in 2015 were significantly reduced in Beijing and its surroundings. During the WCP, aerosol optical depth was reduced most significantly in Beijing, while NO2 and SO2 were reduced most significantly in Hebei and Tianjin, respectively. The meteorological conditions were also favorable during this period. During the WCP, the North China Plain was located under high pressure from the north of China. A southward pressure gradient force and weak northerly and northeasterly winds blocked the transport of pollution from southern and western parts of the industrial area （Hebei, Shanxi and Shandong provinces）. Cold air masses pushed southwards weakly. These conditions were beneficial to the removal of air pollutants in Beijing.