【作者】 钤伟妙； 张艳品； 陈静； 张立霞；

【Author】 QIAN Weimiao;ZHANG Yanpin;CHEN Jing;HAN Juncai;Shijiazhuang Meteorological Bureau;

【机构】 石家庄市气象局；

【摘要】 为探索石家庄的区域输送规律,确定主要污染源区,利用HYSPLIT（Hybrid Single Particle Lagrangian Integrater Trajectory）后向轨迹模式和NCEP的GDAS全球气象要素数据,对2013—2016年从不同高度上抵达石家庄地区的逐日72 h气流后向轨迹进行聚类分析,并结合石家庄逐小时颗粒物污染物浓度数据,分析石家庄PM_2.5的潜在源贡献因子（WPSCF）和浓度权重轨迹（WCWT）。结果表明,（1）石家庄PM_2.5浓度具有明显单峰谷日变化,秋冬季与春夏季峰谷值出现时间不同;（2）近地层大气污染输送路径以近距离,移速慢的轨迹为主,轨迹较短的路径所占比例在40%以上。除夏季外,近距离输送路径均存在螺旋转向,在后向48³6 h内轨迹端点到达河北省内,转为东向和南向输送。（3）大气污染输送通道的垂直分布特征表明,输送轨迹中低于500 m高度的轨迹点占28.7%,高于1000 m低于3000 m高度的轨迹点占36.1%,高于3000m高度的轨迹点占25.3%。低层多以近距离输送为主,高度越高,近距离输送轨迹的频率越低。500 m高度输送通道仍以近距离输送为主,并存在螺旋转向,1500 m高度以上多远距离输送。（4）石家庄PM_2.5的主要污染源区范围较小。途径河北中南部、河南北部、山东西部和山西中北部地区的轨迹对石家庄PM_2.5的污染贡献最大。更多还原

【Abstract】 In order to investigate regional transportation and identify potential source areas of PM_2.5 in Shijiazhuang, the cluster analysis of 72-hour backward trajectories during 2013 to 2016 was conducted, based on the Hybrid Single Particle Lagrangian Integrater Trajectory（HYSPLIT） model and global data assimilation system（GDAS） meteorological statistics. Coupled with hourly pollutant concentration data, the weighted potential source contribution function（WPSCF） and weighted concentration-weighted trajectory（WCWT） were studied. The results show that:（1）Particle pollutants’ concentration showed evident diurnal variation with the unimodal distribution, and the occurrence time of extremum were different during hot and cold seasons.（2） The pollutant transport channels near the ground featured by short distance and slow airflow, which the short distance pathway accounted for more than 40%. Except for summer, there was spiral steering in the short distance transportation pathway, showing that the trajectory arrived at Hebei Province and then turned east or south in the backward 48 to 36 h.（3） The percentages of trajectories below 500 m were 28.7%, above 1000 m but below 3000 m were 36.1%, while above 3000 m were 25.3%. The vertical structures of pollutant transport channels indicated that the short distance channels were dominant, suggesting that the higher the altitude, the less frequency of short distance channels is. At 500 m level, the short distance transport is dominant with the spiral steering trend, contrast to the long distance above 1500 m.（4） The main pollution source areas of PM_2.5 was small inShijiazhuang. The trajectories through the middle and southern parts of Hebei, northern Henan, Western Shandong and the middle and northern parts of Shanxi contributed greatly to the PM_2.5 pollution in Shijiazhuang.更多还原