2022年广西两次低温雨雪冰冻过程分析  

Analysis of two low temperature rain and snow freezing processes in Guangxi in 2022

作　　者：李生艳 梁嘉颖 覃皓 董雪晗 黄晴 刘国忠 LI Shengyan;LIANG Jiaying;QIN Hao;DONG Xuehan;HUANG Qing;LIU Guozhong(Guangxi Meteorological Observatory,Nanning 530022,China)

机构地区：[1]广西壮族自治区气象台,南宁530022

出　　处：《气象研究与应用》2023年第4期85-90,共6页Journal of Meteorological Research and Application

基　　金：中国气象局复盘总结专项(FPZJ2023-095);广西壮族自治区气象局创新平台专项(BNCO-N202304)。

摘　　要：利用常规观测资料和美国国家环境预报中心(NCEP)、美国国家大气研究中心(NCAR)再分析资料,通过天气诊断分析方法,对2022年初广西两次低温雨雪冰冻天气过程进行分析。结果表明:(1)两次过程共同点是亚洲中高纬稳定的西高东低异常经向环流和活跃的南支波动,使冷暖气团长时间在广西交绥,造成持续低温雨雪冰冻天气;特殊温湿层结导致降水相态复杂;冬季强降水发生在弱对称不稳定层结条件下。(2)2月18—25日比1月28—2月5日过程雨雪范围广、强度强,主要由于2月18—25日过程具有更强的动力、水汽条件和冷空气势力偏强。(3)两次过程降温主要受冷平流和垂直输送的共同作用,非绝热加热项均起到增温的作用,2月18—25日过程冷空气更为深厚,垂直输送项在降温前期贡献较大,中层潜热加热作用较明显,与水汽相变有一定联系。Based on the conventional observation data and NCEP/NCAR reanalysis data,two cold rain,snow and freezing weather processes in Guangxi in early of 2022 are analyzed through weather diagnostic analysis methods.Results show that:(1)There are similarities between the two processes.The stable abnormal circulation over Asia continent in mid-high latitude and active southern trough over low latitudes,make the cold and warm air cooperates over Guangxi for a long time,resulting in cold rain,snow and freezing weather.The special humidity and temperature stratification leads to complicated precipitation phases.The heavy precipitation occurs in weak conditional symmetric instability in winter.(2)The process on February 18 to 25 has a wider range of influence,stronger intensity than the process on January 28 to February 5,mainly due to the stronger dynamic condition,water vapour conditions and stronger cold air.(3)The cooling of the two processes is mainly due to the joint effect of cold advection and vertical transportation and the non-adiabatic heating play a role in warming.The process on February 18 to 25 has deeper cold air and vertical transportation contributing more in the pre-cooling period,and the mid-level latent heat being more obvious in connection with phase transition of water vapor.

关 键 词：低温雨雪冰冻 冬季暴雨 降温机制 降水相态 

分 类 号：P429[天文地球—大气科学及气象学]