|关键词: 青岛市 空气污染 沙尘传输 细颗粒物 离子组成 后向轨迹
|Analysis of a Mixed Air Pollution Process of PM2.5 and Dust in Qingdao in 2021
WEI Wei, WANG Wei, ZHANG Yu-qinget al1,2
1.Qingdao Ecological Environment Monitoring Center of Shandong Province, Qingdao, Shandong 266000, China;2.Qingdao Jimeilai Technology Co. Ltd., Qingdao, Shandong 266000, China
|Based on the monitoring data of Qingdao automatic air station in March 2021, with the help of environmental meteorological lidar, aerosol lidar and on-line ion chromatograph data, and using the backward trajectory model (HYSPLIT), a comprehensive analysis has made on the air pollution process, meteorological conditions, particle composition and transmission path of PM2.5 and sand dust mixture in Qingdao. The results showed that the main causes of PM2.5 pollution in the first stage were quiet wind, high humidity, vertical temperature inversion and multiple pollutant transportation from high altitude to the ground. The concentrations of NO-3, SO2-4and NH+4 accounted for 51.7%, 24.8% and 22.4% of the total concentration of water-soluble ions respectively, and the sum of the three accounted for 52.3% of PM2.5 concentration. Motor vehicle sources, industrial sources and combustion sources contributed a lot. Among them, the influence of vehicle source was the most significant. In the second stage, the change of particle concentration in each sub station showed obvious transmission characteristics, the concentration of Ca2+ in PM2.5 increased to 6 times of that in the first stage, and the influence of dust sources was significant. The polluted air mass mainly came from Mongolia and Inner Mongolia. In the early stage, it directly arrived at Qingdao from Northwest China, and in the later stage, it reached southeast Qingdao via Bohai Bay and Yantai, and finally returned to Qingdao. The weak cold high pressure led to unfavorable horizontal diffusion conditions near the ground, and PM10 concentration remained at a high level for a long time.
|Key words: Qingdao city Air pollution Dust transportation PM2.5 Ion composition Backward trajectory