2021年11月两次黄淮气旋引发的东北地区暴雪过程对比分析  

Comparative analysis of two snowstorm events in Northeast China caused by Huang-Huai cyclones in November 2021

作　　者：杜晓丹 赵宇[1] 赵玲[2] DU Xiaodan;ZHAO Yu;ZHAO Ling(Key Laboratory of Meteorological Disaster,Ministry of Education/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/International Joint Laboratory on Climate and Environment Change,Nanjing University of Information Science&Technology,Nanjing 210044,China;Heilongjiang Provincial Meteorological Observatory,Harbin 150028,China)

机构地区：[1]南京信息工程大学气象灾害教育部重点实验室/气象灾害预报预警与评估协同创新中心/气候与环境变化国际合作联合实验室,江苏南京210044 [2]黑龙江省气象台,黑龙江哈尔滨150028

出　　处：《冰川冻土》2024年第6期1800-1815,共16页Journal of Glaciology and Geocryology

基　　金：国家自然科学基金项目(41975055)资助。

摘　　要：受黄淮气旋影响,2021年11月7—9日和21—23日在我国东北地区分别出现了两次暴雪天气过程。为寻找监测指标,改进预报技术,本文利用常规观测、FY-4A红外云图,结合欧洲中期天气预报中心(ECMWF)0.25°×0.25°逐小时的ERA5再分析资料,对这两次暴雪过程进行了对比分析。结果表明,前者是黄淮气旋单独北上,气旋路径偏西,在东北地区停留时间长,强降雪范围大,出现了雨、雨夹雪和雪等复杂降水相态;而后者是黄淮气旋与蒙古气旋合并,气旋路径偏东,在东北地区停留时间短,强降雪范围小,以纯雪为主。两次过程的云系演变均呈现Shapiro-Keyser气旋发展模式,具有暖锋后弯和锢囚包卷特征,前者宽广的暖锋云系控制内蒙古东部和东北地区,导致大范围强降雪,而后者暖锋云系在东北地区东部,造成强降雪范围小;降雪强度与反射率大于30 dBZ的中尺度降水区的强度和持续时间密切相关。两次暴雪过程的水汽和热动力条件有很大不同:前者受热带扰动外围水汽输送的影响,有2条水汽通道,输送来自日本海、黄海和东海的水汽,而后者只有1条水汽通道,输送来自日本海的水汽;前者的水汽辐合、暖平流和锋生都强于后者,因此较后者有更强的降水。两次过程中东北地区西部整层温度一直低于0℃,以降雪为主,而7—9日过程吉林东部和辽宁东部冷空气影响前地面温度较高,为降雨,有些地区地面温度虽然低于0℃,但900~800 hPa出现暖层,冰晶融化,出现雨夹雪和冻雨,冷空气主力下来后转雪。本文通过对比分析这两次暴雪过程,尝试寻找黄淮气旋暴雪的预报监测指标,可为黄淮气旋暴雪预报提供参考。Under the influence of Huang-Huai cyclones,two heavy snowstorm events hit northeastern China on 7—9 and 21—23 November 2021,respectively.In search of monitoring indicators and improved forecasting techniques,this paper uses conventional observation data,FY-4A infrared cloud images,combined with the 0.25°×0.25° hourly ERA5 reanalysis data from the European Center or Medium-Range Weather Forecasts(ECMWF) to make a comparative analysis of the two snowfall events.The results show that:(1) in the former,the Huang-Huai cyclone moved northward alone,with the cyclone track more westerly,and stayed in northeastern China for a long time,with a wide range of heavy snowfall,and complex precipitation phases,such as rain,sleet,and snow;whereas,in the latter,the Huang-Huai cyclone merged with the Mongolian cyclone,with the cyclone track easterly,and stayed in northeastern China for a short time,and with a small extent intense snowfall,with pure snow as the primary precipitation phase.(2) The cloud evolution of the two cyclones both show a Shapiro-Keyser development model with the back-bent warm front and wrapping occlusion characteristics,with the former broad warm frontal cloud controlling eastern Inner Mongolia and northeastern China,causing widespread heavy snowfall,while the latter warm frontal cloud is in the eastern part of northeast China,resulting in a small range of heavy snowfall.Snowfall intensity is strongly correlated with the intensity and duration of mesoscale precipitation areas with reflectivity greater than 30 dBZ.(3) The water vapor and thermodynamic conditions of the two snowstorms are very different:the former is affected by the transport of water vapor from the periphery of tropical disturbances,with two water vapor channels transporting water vapor from the Sea of Japan,the Yellow Sea and the East China Sea,whereas the latter has only one water vapor channel transporting water vapor from the Sea of Japan,and the water vapor convergence,warm advection and frontogenesis of the former are stronger tha

关 键 词：暴雪 黄淮气旋 暖锋后弯 水汽 降水相态 

分 类 号：P458[天文地球—大气科学及气象学]