风廓线雷达在成都地区冬季典型连续颗粒物污染过程分析中的应用

Analysis of typical continuous particulate pollution processes in winter Chengdu base on wind profile radar

利用大气细颗粒物(PM_(2.5))和可吸入细颗粒物(PM_(10))的质量浓度和边界层风廓线雷达等资料,对2016年12月1—24日和2019年12月7—17日成都地区两次连续颗粒物污染过程进行分析,并就此探讨成都地区冬季重污染过程的形成机制。结果表明:水平风速风向、垂直风速和大气折射率结构常数的变化对颗粒物浓度的变化具有指示意义;通风量与PM_(2.5)、PM_(10)浓度显著负相关;当通风量跃增,0~3000 m高度的水平风速大于10 m/s,同时配合降水清除作用,将导致重污染过程结束。通过后向轨迹模拟分析,两次连续污染过程的污染物传输方向不同,导致两次连续污染过程的主要污染物存在不同。

Using the PM_(2.5) and PM_(10) mass concentrations as well as the data from the boundary layer wind profiler radars,this paper analyzed the two consecutive particle pollution processes in Chengdu from December 1 to 24,2016 and December 7 to 17,2019.Base on which,the paper explored the formation mechanism of the heavy pollution process in Chengdu in winter.The results showed that the variations of horizontal wind speed and direction,vertical wind speed and atmospheric refractive index structure constant had indicative significance for the variation of particle concentration.There was a significant negative correlation between the ventilation volume and the concentrations of PM_(2.5) and PM_(10).When the ventilation volume jumped,the horizontal wind speed from 0 to 3000 m was greater than 10 m/s,and at the same time cooperated with the removal of precipitation,it would led to the end of the heavy pollution process.Through backward trajectory simulation analysis,the transport directions of pollutants in the two consecutive pollution processes were different,resulting in different main pollutants in the two consecutive pollution processes.