2021年3月沈阳地区一次污染过程气溶胶垂直变化特征及成因分析  

Aerosol vertical variations and the origin analysis on a pollution event in Shenyang on March 2021

作　　者：李潇潇 赵胡笳[1] 马雁军[1] 刘晓初 李思绪 李晓岚[1] 王扬锋[1] 洪也[1] Xiao-xiao LI;Hu-jia ZHAO;Yan-jun MA;Xiao-chu LIU;Si-xu LI;Xiao-lan LI;Yang-feng WANG;Ye HONG(Institute of Atmospheric Environment,China Meteorological Administration,Shenyang 110166,China;Dalian Meteorological Observatory,Dalian 116001,China)

机构地区：[1]中国气象局沈阳大气环境研究所,辽宁沈阳110166 [2]大连市气象台,辽宁大连116001

出　　处：《气象与环境学报》2022年第2期46-54,共9页Journal of Meteorology and Environment

基　　金：国家自然科学基金面上项目(41875157);国家重点研发计划项目(2016YFC0203304,2017YFC0212301)共同资助

摘　　要：利用地面大气颗粒物质量浓度观测资料、探空和NECP再分析资料以及地面激光雷达探测资料,对2021年3月13—15日沈阳地区污染事件过程展开分析,探讨大气污染物质量浓度、大气环流背景与气溶胶垂直分布等特征。结果表明:3月13日PM_(2.5)质量浓度最高值出现在06:00—07:00,约为220.0—230.0μg·m^(-3),15日12:00开始显著降低,而PM_(10)质量浓度在15:00出现显著增加,为258.3μg·m^(-3)。SO_(2)和NO_(2)浓度较高值均出现在3月13日10:00时左右,分别为40.1μg·m^(-3)和101.3μg·m^(-3)。CO质量浓度最高值出现在13日16:00—17:00,约为8.8 mg·m^(-3)。沈阳地区臭氧的最高值均出现在午后,13日和14日午后(12:00—16:00)臭氧最大值为102.4—113.7μg·m^(-3)。蒙古气旋东移过程中逐渐发展加强,其后部西北风将沙尘向东南方向输送。沈阳地区沙尘发展旺盛时存在不稳定层结,同时伴有显著的上升运动,有利于沙尘粒子的垂直混合和向下游输送。3月15日02:00(北京时间15日10:00)气溶胶消光最大值出现在0.7 km处,消光系数约为6.0 km^(-1)。近地面激光雷达退偏比显著增加至0.4—0.5,近地面以非球形粒子(粗颗粒物)为主的沙尘或浮尘。Based on the observation data of particulate matter mass concentration,radiosonde data,NECP reanalysis data and ground-based Lidar,a pollution event in Shenyang from March 13 to 15,2021 was analyzed.The variations of PM concentration,atmospheric circulation background and aerosol vertical distribution were discussed.The results show that PM_(2.5) mass concentrations peaked at 06:00-07:00 on March 13 with the values of 220.0-230.0μg·m^(-3),followed by a significant decline at 12:00 on March 15 and a significant enhancement of PM_(10) at 15:00 with the concentrations up to 258.3μg·m^(-3).High levels of SO_(2) and NO_(2) appeared at about 10:00 on March 13 with the concentrations of 40.1μg·m^(-3)and 101.3μg·m^(-3),respectively.The maximum concentration of CO appeared between 16:00 and 17:00 on March 13 with the values of around 8.8 mg·m^(-3).The highest levels of ozone always appeared in the afternoon with the values of 102.4-113.7μg·m^(-3) from 12:00 to 16:00 on March 13 and 14.Due to the enhancement of Mongolian cyclone during its eastward moving,the dust was transported southeast by the northwest wind.The unstable stratification appeared while the dust was flourishing in Shenyang,accompanied by significant upward movement,which was conducive to the vertical mixing and transport downstream of dust particles.The maximum aerosol extinction appeared at the height of 0.7 km with the values of around 6.0 km^(-1) at 10:00 on March 15,when the surface lidar depolarization ratio significantly increased to 0.4-0.5,indicating that the dust or floating dust was dominated by non-spherical particles(coarse particles).

关 键 词：污染天气 颗粒物浓度 天气形势 垂直消光 

分 类 号：X16[环境科学与工程—环境科学]