中文摘要：

利用MODIS（the Moderate Resolution Imaging Spectroradiometer）影像对2015-04-15影响呼和浩特市的一次沙尘天气进行了系统判读,并分析了沙尘天气过程中气象要素变化及其对空气质量的影响,以期为沙尘天气环境影响评价提供理论依据。遥感影像显示该次沙尘天气主要起源于内蒙古中西部,利用MODIS彩色合成影像可以识别沙尘信息,实现沙尘天气过程的监测,并判明沙尘源和影响范围等。沙尘天气过程气象要素变化分析表明该次沙尘天气由冷空气过境引发,低温大风天气有利于沙尘天气的发生。沙尘天气引起空气质量急剧下降,出现严重污染,沙尘高空远距离输送是导致呼和浩特市空气质量显著下降的重要原因。大气污染主要由颗粒物（PM（10））的增加引起,但大风使CO、NO2、SO2等污染物浓度大幅度下降,具有清除人为源所排放污染物作用。

英文摘要：

MODIS was used to observe a dust event occurred on April 15, 2015, which covered the city of Hohhot, Inner Mongolia, and then the changes of meteorological conditions and the impacts of aeolian dust on air quality were analyzed. Satellite images showed that the dust originated from the middle and west of Inner Mongolia, MODIS composite images therefore could be used to discriminate dust, to monitor dust process and to identify dust source and influence range. Analysis on the meteorological factors demonstrated this dust was caused by cold air, low temperature and strong wind conduced to aeolian dust. Dusty weather decreased air quality, resulting in severe air pollution, and long-distance transport of dust aerosol in the upper air contributed much to air quality deterioration caused by the dust event. The air pollution was caused by the increase of PM10, and strong wind accompanied the dust decreased concentrations of some pollutants including CO, NO2 and SO2. Therefore, while the dust event increased PMlo, and the strong wind diluted and carded away some man-made pollutants.