阿拉善盟2022年4月26日大风沙尘天气形成机制研究  

Study on the Formation Mechanism of Gale Sand Dust Weather in Alxa League on April 26, 2022

作　　者：杨嘉琦 Yang Jia-qi(Alxa League Meteorological Bureau,Alxa League,Inner Mongolia 750306)

机构地区：[1]阿拉善盟气象局,内蒙古阿拉善盟750306

出　　处：《农业灾害研究》2023年第1期79-81,共3页Journal of Agricultural Catastrophology

摘　　要：利用地面、高空区域自动站常规观测资料以及NCEP/NCAR(2.5°×2.5°)再分析资料,对2022年4月26日阿拉善盟大风沙尘天气过程进行分析。结果表明:(1)大气中低层锋区增强,配合地面冷高压南压触发阿拉善盟大风沙尘天气;(2)强沙尘暴发生区域内,在中小尺度次级环流作用下,地面偏东风风速增大,同时伴有强烈的垂直而运动;(3)温度平流与高低层大气流速构成正反馈,在正反馈机制作用下,暖平流使地表沙尘粒子受热上升做上升运动,同时有利于地面风速增大;(4)垂直速度对判断沙尘天气范围、强度以及最小能见度出现时间具有指导意义;(5)阿拉善盟境内巴丹吉林、乌兰布和及腾格里三大沙漠是主要沙源,为沙尘天气的发展与维持提供物质基础。Conventional observation data of automatic stations on the ground and at high altitude and NCEP/NCAR(2.5 ° ×2.5 °) reanalysis data was used to analyze the gale sand dust weather process in Alxa League on April 26, 2022. The results showed that:(1) The strengthening of the middle and lower atmospheric frontal zone combined with the southward pressure of the surface cold high triggered the gale sand dust weather in Alxa League;(2) In the strong dust storm area,the surface easterly wind speed increases,accompanied by strong vertical upward movement under the effect of the meso and small scale secondary circulation;(3)The temperature advection and the upper and lower atmospheric velocity form a positive feedback. Under the positive feedback mechanism, the warm advection made the surface dust particles rise and move upward when heated, which wss beneficial to the increase of the surface wind speed;(4) The vertical velocity is of guiding significance in judging the range, intensity and minimum visibility of sand dust weather;(5) The Badain Jaran, Ulan Buhe and Tengger deserts in Alxa League were the main sand sources,providing material basis for the development and maintenance of dust weather.

关 键 词：大风沙尘 次级环流 温度平流 垂直速度 

分 类 号：P425.55[天文地球—大气科学及气象学]