内蒙古一次极端暴雪事件中冻雨成因分析  

Cause Analysis of Freezing Rain in an Extreme Snowstorm in Inner Mongolia

作　　者：孟雪峰 孙永刚 霍志丽 萨日娜 孔文甲 刘梦迪 MENG Xuefeng;SUN Yonggang;HUO Zhili;SA Rina;KONG Wenjia;LIU Mengdi(Inner Mongolia Meteorological Observatory,Hohhot 010051,China;Inner Mongolia Meteorological Service Center,Hohhot 010051,China;Tongliao Meteorological Observatory,Tongliao 028000,China)

机构地区：[1]内蒙古气象台,内蒙古呼和浩特010051 [2]内蒙古气象服务中心,内蒙古呼和浩特010051 [3]通辽市气象台,内蒙古通辽028000

出　　处：《沙漠与绿洲气象》2022年第4期22-30,共9页Desert and Oasis Meteorology

摘　　要：利用常规观测资料、地面自动站资料、NCEP 1°×1°再分析资料及雷达资料等对2020年11月18—19日发生在内蒙古东南部罕见历史极值特大暴雪事件背景下的通辽市冻雨灾害天气成因进行分析。结果表明:(1)冻雨发生时地面气象要素特征为地面气温稳定,降水量和降水强度较小。(2)存在典型的“冷—暖—冷”层结特征,近地层930-860 hPa存在强逆温层,气温0℃以上和0℃以下两个层结在探空T-lnP图中面积相当。(3)近地层冷垫是强冷高压南侵,受到江淮气旋和地形阻挡,在平原地区堆积形成,有持续的冷空气补充。(4)中层暖区融化层在700、850 hPa低涡前部,西南暖湿低空急流顶端到达冷垫上空并沿冷垫爬升叠置,持续的暖平流特征明显。(5)地面冷垫与中层暖层之间有明显的锋区特征,雷达观测在冻雨区具有回波强度增大的特征。Based on conventional observations,ground automatic station data,NCEP 1°×1°reanalysis data,radar and other multi-source data,the causes of the freezing rain disaster in Tongliao on 18-19 November 2020 were analyzed under the background of rare historical extreme snowstorm events in southeast Inner Mongolia.The results show that:(1)During the freezing rain period,the surface mteorological elements are characterized by stable temperature,less precipitation and lower rainfall intensity.(2)There is a typical“cold-warm-cold”stratification,which exists a strong inversion layer from 930 to 860 hPa near the ground.The two stratifications of temperature above and below 0℃ are similar in the radiosonde T-lnP(.3)Near-surface cold pad is formed by southward invasion of strong cold high pressure,blocked by Jianghuai cyclone and terrain in plain area,and gets continuous nearsurface cold advection supplement.(4)The melting layer in the middle warm zone is at the front of the 700 and 850 hPa vortexes.The top of the southwest warm-wet low-level jet reaches over the cold pad and is formed by climbing and stacking along with the cold pad.The continuous warm advection has obvious characteristics.(5)There are obvious frontal characteristics between the near-surface cold pad and melting layer in the middle warm zone,and radar observation has obvious characteristics of increasing echo intensity in the freezing rain area.

关 键 词：极端暴雪 冻雨“ 冷—暖—冷”层结 云图特征 

分 类 号：P458.121[天文地球—大气科学及气象学]