摘要
利用常规观测资料、ERA-Interim、NCEP/NCAR再分析资料,对比分析了2016年1月21—26日和2018年12月28日至2019年1月2日影响广西柳州的2次低温雨雪冰冻天气的成因。结果表明:2次过程期间中高纬均为两槽一脊形势,阻塞高压较常年同期偏强28dagpm;2018年过程期间近地层强冷平流的持续输送和高层冷空气的补充是柳州2018年气温低于2016年的重要原因,中低层持续的水汽输送及水汽辐合,长时间逆温层维持以及较强的逆温强度使得降雪持续时间及范围强于2016年;2016年过程期间中层强盛的西北气流使冷空气南下迅速,700hPa急流区以及850hPa风速辐合区的偏南导致明显的降雪主要出现在广西南部,柳州只出现少量降雪,温度回升较快。
Based on the meteorological observation data,ERA-Interim and NCEP/NCAR reanalysis data,two low-temperature freezing rain/snow weather events affecting Liuzhou from 21 to 26 January 2016 and from 28 December 2018 to 2 January 2019 are compared.The results show that:during the two processes,the middle high latitude was in the pattern of two troughs and one ridge,and the blocking high pressure was 28 dagpm stronger than that in the same period of the normal year;the continuation of cold advection transportation and the supplement of cold air flow at upper levels was an important reason for the lower temperature in 2018 than in 2016;continuous moisture convergence in the middle-lower layer,long-term inversion layer maintenance and strong inversion intensity made the duration and range of snowfall stronger in 2018 than in 2016;the strong northwest airflow in the middle layer made the cold air move southward rapidly during the process of 2016.The jet stream at 700 hPa and the wind speed convergence zone were more southern than normal at 850 hPa,resulting in the snowfall mainly in the southern Guangxi,while there was only a small amount of snow in Liuzhou,and the temperature was rising quickly.
作者
刘蕾
张凌云
李宜爽
李家文
LIU Lei;ZHANG Lingyun;LI Yishuang;LI Jiawen(Liuzhou Meteorological Service,Guangxi,Liuzhou 545001)
出处
《气象科技》
2020年第1期107-114,共8页
Meteorological Science and Technology
基金
广西重点研发计划(桂科AB19110028)资助.
关键词
低温
雨雪冰冻
阻塞高压
强锋区
low temperature
extreme freezing rain and snow
blocking high
strong frontal zone
