山东省“雷打雪”事件分型及其成因分析  

Classification and Cause Analysis of “Thundersnow” Event in Shandong

作　　者：郑丽娜 张子涵 夏金鼎 ZHENG Lina;ZHANG Zihan;XIA Jinding(Dongying Meteorological Office of Shandong Province,Dongying 257091)

机构地区：[1]山东省东营市气象局

出　　处：《气象》2019年第8期1075-1084,共10页Meteorological Monthly

基　　金：国家自然科学基金项目(41475038);中国气象局预报员专项(CMAYBY2018-042);山东省气象局面上课题(2015sdqxm02)共同资助

摘　　要：利用闪电定位仪、加密地面自动站和常规资料分析了2006—2015年发生在山东的35次"雷打雪"事件,按照形成机制将其分为暖平流型和海效应型"雷打雪"两类,并细致归纳了两类事件发生时有关要素场及物理量场等方面的特征。主要结论如下:暖平流"雷打雪"事件发生前24 h内,对流层中低层是升温的,且越接近地面升温越明显;事件发生在850 hPa至地面有强冷空气突然入侵之时,此时上下温差可达10℃;环流形势也由上下一致的偏南气流调整为低层为冷垫,中高层为暖平流;上升运动中心及不稳定层结集中出现在对流层的中高层。海效应"雷打雪"事件发生前两天,渤海被暖脊控制,海面温度较平时升高2℃左右;在高空槽后的偏北气流猛然增大横扫渤海时,"雷打雪"事件发生;尽管对流活动也发生在对流层低层,但是其不稳定层结的厚度及上下温差较一般海效应降雪要大。Using the data of lighting locator,densely-obtained automatic station data and conventional data,35 "thundersnow" events that occurred in Shandong Province from 2006 to 2015 are analyzed.The "thundersnow" can be divided into warm advection type and marine effect type according to the formation mechanism,and the characteristics in related element fields and physical quantity fields for the two kinds of events are summarized in detail.The main conclusions are as follows.Within 24 h before warm advection "thunderstorm" events, the temperature in the middle and lower troposphere is warming up,and the closer it is to the ground,the more obvious the temperature rise is.The events tend to occur when there is a sudden invasion of strong cold air from 850 hPa to the ground,the temperature difference between the upper and lower layers can reach 10 ℃,and the circulation situation is adjusted from uniform southward airflow to cold cushion in lower layer and the warm advection in the mid-upper layers.The center of ascending motion and the unstable stratification appear in the mid-upper layers.Two days before the marine effect"thunderstorm"events,the Bohai Sea is controlled by warm ridges,and the sea surface temperature is about 2 ℃ higher than usual.When the northward current behind the upper trough suddenly increases and sweeps across the Bohai Sea,the"thundersnow"events occur.Although convective activity also occurs in the lower troposphere,the thickness of unstable stratification and the temperature difference between upper and lower layers are larger than that in marine effect snowstorm in general.

关 键 词：“雷打雪”事件 暖平流型 海效应型 条件不稳定 

分 类 号：P445[天文地球—大气科学及气象学]