中文摘要：

根据2001—2012年环保部发布的哈尔滨市城市空气质量日报数据及同期气象资料分析了哈尔滨市空气污染指数（API）的变化特征.结果表明,哈尔滨市空气污染呈现明显的北方季节变化特征,API冬、春季高,夏、秋季低,供暖期高于非供暖期.哈尔滨市空气污染以可吸入颗粒物为首要污染物,空气质量状况以良居多,占总样本数的75.4%.从年际变化来看,空气质量有了一定的改善,12年间空气污染指数呈显著下降的趋势.哈尔滨市空气污染指数与风速呈显著正相关,与降水量、气温、能见度呈显著负相关.后向轨迹分析结果表明,哈尔滨市出现中度以上污染时,其气团来源体现了3种不同的特征.

英文摘要：

The characteristic of air quality and its influencing factors are analyzed based on the daily report data of urban air quality and meteorological data in Harbin from 2001 to 2012. The seasonal change of the air pollution index （API） in Harbin showed relatively high in winter and spring and relatively low in summer and fall. The values of API were obviously higher in heating season than that in non-heating season. In Harbin, the key pollutant was inhaleble particles. In 75.4% of the days, the air pollution levels showed good and moderate. During the 12 years, a significant decreasing trend of API indicates the improvement of air quality in Harbin. The variations of meteorological parameters can influence the level of air pollutants, which show a positive correlations between API and wind speed, and a negative correlations between API and rainfall, air temperature, and visibility. The pattern and origination of the middle-polluted air mass appeared in Harbin was analyzed by backward trajectory analysis.