基于后向轨迹聚类分析的青岛市大气污染输送来源研究

The study of air polluted transportation and source in Qingdao based on backward trajectory clustering

利用HYSPLIT轨迹模式,通过后向轨迹聚类分析对青岛市2015~2017年气团来源进行分类,并统计每一类轨迹对应的颗粒物浓度(PM_(10)、PM_(2.5))和臭氧浓度(O_(3))及相对应的气象要素(温度、风速、湿度等),探讨不同类别气团对青岛市环境空气质量的影响。结果表明:1.来自西北方向的中长距离和短距离传输,对青岛市颗粒物浓度贡献较大;来自西南方向的中长距离传输和西北方向的短距离传输对青岛市O_(3)浓度贡献较大;来自东南方向的海上气团较为清洁,三项污染物浓度均较低。2.采暖季气流后向轨迹分析表明,静稳高湿的气象条件可能是导致西北方向短距离传输PM2s浓度偏高的原因;来自西北方向的中长距离传输PM_(2.5)浓度偏高,与气团途径区域污染物输送有关。3.5-9月气流后向轨迹分析表明,来自海上的气团较为清洁,虽然其温度较高有利于O_(3)的生成,但由于生成O_(3)的前体物浓度较低,因此O_(3)浓度最低;来自内陆的短距离传输,温度较高,且气团运动缓慢,有利于O_(3)的生成和积累。本研究分析了青岛市不同类别气团的污染特征,对青岛市大气污染的精准化管控和区域联防联控具有重要意义。

Based on the backward trajectory clustering analysis of HYSPLIT trajectory model,the sources of air mass in Qing-dao city from 2015 to 2017 were classified.Particulate matter(PM_(10) and PM_(2.5))concentration,ozone(O_(3))concentration,mete-orological elements(temperature,wind speed,humidity,etc.)of backward trajectories for each type were counted to discuss the influence of different air masses on the ambient air quality in Qingdao.The results showed that:①The medium-and-long dis-tance and short distance transportation from the northwest made a great contribution to particulate concentration in Qingdao.Medi-um-and-long distance transportation from southwest direction and short distance transportation from northwest direction contributed more to O_(3) concentration in Qingdao.Oceanic air masses from the southeast were cleaner,in which concentrations of all three pol-lutants were lower.②The analysis of the airflow backward trajectory in the heating season showed that stable meteorological con-ditions with high relative humidity may be the cause of the highest concentration of PM_(2.5) in the short distance transportation from northwest.The concentration of PM_(2.5) was relatively higher in the medium-and-long distance transportation from the northwest.It may be related to air mass passing through heavily polluted areas.③The backward trajectory analysis from May to September showed that oceanic air mass was relatively clean.O_(3) concentration of oceanic air mass was the lowest due to the low precursor concentration,although whose high temperature was conducive to the formation of O_(3).The short distance air mass from inland with higher temperature and slower moving speed was conducive to the generation and accumulation of O_(3).This study analyzed the pollution characteristics of different air masses in Qingdao,which was of great significance for the precise control and regional joint control of air pollution in Qingdao.