华中地区高空背景点位大气污染物浓度受区域传输的影响研究

Study on Influence of Atmospheric Pollutant Concentration at High Altitude Background Point in Central China by Regional Transmission

利用HYSPLIT模式和全球资料同化系统气象数据,计算2018年每日抵达华中高空背景点区域的后向气流轨迹,结合衡山国家空气背景监测点大气污染物同期数据,探讨该区域大气污染传输特征。结果表明(1)起始于背景点区域周边城市群的慢速低空气团对背景点空气质量影响较大。(2)起始于西北区域高空高速气流,对背景点PM10浓度影响最大,PM2.5浓度仅占PM10浓度的26.7%。(3)海洋性气团在秋季和冬季对背景点污染物清除作用明显。

Using HYSPLIT model and global data assimilation system meteorological data,the backward air flow trajectory arrived at the high-altitude background area of Central China in 2018 was calculated.Combined with the clustering method and the national atmospheric background monitoring data of Hengshan background station in the same period,the characteristics of air pollution transmission in this region were discussed.The results showed that:(1)The slow-speed low-air masses start from the surrounding urban agglomerations,which had a greater impact on the air quality of the background points.(2)The high-altitude high-speed airflow starting in the northwest region had the greatest influence on the PM10 concentration at the background point,and the PM2.5 concentration only accounted for 26.7%of the PM10 concentration.(3)Marine air masses had a clear effect on the removal of pollutants at background points in autumn and winter.