回流作用对江淮地区两次浮尘天气过程影响的差异研究
A comparative study on the influence of the reflux effect on the two dust weather in the Jianghuai region
王蓓元 1谢真珍 1安礼政 1宋昊冬 1肖晨1
作者信息
摘要
本文以2021年3月16、28日两次沙尘天气为例,利用地面常规气象观测资料、气象再分析资料,结合气溶胶激光雷达、风廓线雷达、HYSPLIT模型等分析了影响江淮地区的两次沙尘天气发生时天气系统、颗粒物浓度、气溶胶光学特性和边界层气象条件变化等特征,特别探讨了回流作用的影响.结果表明:两次均为浮尘天气,与暖区新生类蒙古气旋的活动有关.对江淮地区的影响分为冷锋后部污染物影响和高压后部污染物回流影响.前者容易引发单峰型2～4 h污染物爆发性增长,后者对应多峰型7～9h污染物持续增长,最终产生1 000 μg·m-3以上的严重污染.污染物均来源于蒙古和贝加尔湖,经过华北后传输高度降低至1 km以下,回流阶段的传输高度较低,仅为0.3 km左右.传输层风速加强至8～14m·s-1有利于污染物在地面的长时间影响.
Abstract
This paper takes two sandstorms on March 16 and 28,2021 as examples,by using conventional ground meteorological observation data and meteorological reanalysis data,combined with aerosol lidar,wind profile radar,HYSPLIT model,etc.,the weather system,particle concentration,aerosol optical characteristics,and boundary layer meteorological conditions that affect the occurrence of the two sandstorms in the Jianghuai region were analyzed.In particular,the influence of reflux was explored.Results indicate that both times were dust prone weather,which is related to the activity of newly formed Mongolian cyclones in warm regions.The impact on the Jianghuai region can be divided into the influence of pollutants in the rear of the cold front and pollutants in the back of the high pressure.The former is prone to single-peak rapid growth of pollutants within 2-4 hours,while the latter corresponds to multi-peak continuous growth of pollutants within 7-9 hours,eventually leading to severe pollution levels exceeding 1 000 μg·m-3.The pollutants originate from Mongolia and Baikal,and after passing through North China,the transport height decreases to below 1 km,with even lower transport heights of 0.3-0.6 km during the reflux flow phase.An increase in the wind speed at the transport level to 8-14 m·s-1 is beneficial for the long-term dispersion of pollutants at the ground level.
关键词
浮尘/PM10爆发性增长/蒙古气旋/回流/江淮地区Key words
dust/explosive growth of PM10/Mongolian cyclone/reflux/Jianghuai region引用本文复制引用
基金项目
江苏省青年基金(KQ202409)
江苏省青年基金(KQ202324)
出版年
2024
国家科技期刊平台
NSTL
万方数据