摘要
利用常规气象观测资料及NCEP/NCAR(2.5°×2.5°)逐6 h再分析资料等,运用天气学原理和天气动力学诊断分析法,对2020年2月13—15日宁夏寒潮天气过程的环流形势及系统发展演变、大风降温成因等进行诊断分析。结果表明:寒潮前气温回升,强冷空气在西西伯利亚—中西伯利亚上空堆积并爆发南下,造成此次寒潮天气。冷空气取西北路径入侵,横槽转竖南压,地面冷高压完整有规律地向东南方向移动。前期升温,强冷空气入侵后,温度变化剧烈,气温骤降主要是由强冷平流所引起。正涡度平流随高度增加,有利于上升产生绝热冷却,使冷舌增强,强冷平流促使低层锋区加强,气压梯度增大,负涡度平流随高度增加,伴随有较强的下沉运动,高空动量下传及不稳定能量的释放产生地面大风。
Using conventional meteorological observation data,and 6-hourly NCEP/NCAR(2.5°×2.5°)reanalysis data,etc.,the circulation and system development and evolution of the cold wave weather process in Ningxia from February 13 to 15 in2020,as well as the causes of high wind and cooling are diagnosed and analyzed with the weather principles and weather dynamics diagnostic analysis method.The results show that the cold wave is caused by the warming of temperature before the cold wave,and the strong cold air piles up over Western Siberia-Central Siberia and bursts southward.The cold air takes the northwest path to invade,the horizontal trough turned vertical south pressure,and the ground cold high pressure regularly moves to the southeast.After the previous warming and strong cold air invasion,the temperature changes dramatically,and the sudden drop in temperature is mainly caused by strong cold advection.The positive vorticity advection increases with height,which is conducive to the adiabatic cooling generated by the rise,so that the cold tongue is enhanced,the strong cold advection promotes the strengthening of the low-level frontal area,the pressure gradient increases,the negative vorticity advection increases with height,accompanied by a strong sinking motion,the momentum downward transmission of high altitude and the release of unstable energy to produce ground gale.
作者
张泽瑾
ZHANG Zejin(Meteorological Bureau of Zhongwei,Zhongwei 755000,China)
出处
《宁夏工程技术》
CAS
2022年第1期1-6,共6页
Ningxia Engineering Technology
关键词
寒潮
环流形势
诊断分析
cold wave
circulation situation
diagnostic analysis
