2021年11月8日黑龙江南部一次冻雨天气过程成因分析  

Causes of a freezing rain event in southern Heilongjiang province on November 8,2021

作　　者：马国忠 安英玉 关铭[3] 王秋京[4] MA Guozhong;AN Yingyu;GUAN Ming;WANG Qiujing(Artificial Rainfall Office of People′s Government of Heilongjiang Province,Harbin 150030,China;Institute of Atmospheric Environment,China Meteorological Administration,Shenyang 110166,China;Heilongjiang Meteorological Observatory,Harbin 150030,China;Heilongjiang Institute of Meteorological Science,Harbin 150030,China)

机构地区：[1]黑龙江省人民政府人工降雨办公室,黑龙江哈尔滨150030 [2]中国气象局沈阳大气环境研究所,辽宁沈阳110166 [3]黑龙江省气象台,黑龙江哈尔滨150030 [4]黑龙江省气象科学研究所,黑龙江哈尔滨150030

出　　处：《气象与环境学报》2024年第6期19-27,共9页Journal of Meteorology and Environment

基　　金：沈阳大气环境研究所开放基金(2019SYIAE01);黑龙江省气象局科技创新发展项目(HQFZ2022014)共同资助。

摘　　要：选用逐时地面观测数据、探空观测资料和ERA5再分析资料,对2021年11月8日黑龙江省雨雪天气的降水相态特征及其南部一次冻雨天气形成原因进行分析。结果表明:此次过程大气环流背景为高空低涡东移并加强,携带暖湿空气的东南风急流为此次降水过程提供了水汽和能量,由其形成的暖层导致了冻雨天气。此次过程冻雨区大气层结为“冷—暖—冷”结构,高空冷层的冰晶凝华增长形成雪,当雪下落至暖层融化形成雨,雨下落过程中与云滴碰并增长,至近地面冷层保持过冷水形态形成冻雨,属于“冰相融化”机制。大气的中低层暖平流增温对冻雨天气预报有指示作用,低层东北风是导致冷平流产生的重要原因,当有持续、较大的东北风出现时,冷平流增强、冷层气温下降,冻雨强度增强。此外,对比吉林省一次典型冻雨过程表明,当出现暖层、逆温较强的大气层结配置时,冻雨强度较强。Using datasets of the hourly surface observation,upper-air observation,and ERA5 reanalysis,the study analyzes the precipitation phase characteristics and the causes of a freezing rain event in southern Heilongjiang province during the rain-snow weather process on November 8,2021.Results show that the atmospheric circulation background features an eastward-moving and intensifying upper-level low vortex.The southeastern jet stream transporting warm and moist air provides moisture and energy for the precipitation,forming a warm layer that causes the freezing rain.The stratification over the freezing rain area exhibits a"cold-warm-cold"structure.Ice crystal growth produces snow in the upper cold layer,which melts into rain upon entering the warm layer.As the rain descends through the cold layer near the surface,it remained in a supercooled liquid state,forming freezing rain i.e.a process consistent with the"ice-phase melting"mechanism.The warm advection-induced warming[JP2]in the mid-to-lower atmosphere is indicative of freezing rain,while the northeasterly in the lower layer contributes to cold advection.Sustained and strong northeasterly tends to enhance cold advection,causing a temperature drop in the cold layer and increasing the freezing rain intensity.Further comparison with a typical freezing rain event in Jilin province reveals that a strong warm layer and pronounced inversion layer significantly contribute to the intensified freezing rain.

关 键 词：温度平流 暖层厚度 冰相融化 

分 类 号：P458.11[天文地球—大气科学及气象学]