影响山东的MCC分型及其差异性特征  

Subtypes and their distinguishing features of MCCs affecting Shandong

作　　者：罗江珊 李博 万夫敬 任兆鹏 LUO Jiangshan;LI Bo;WAN Fujing;REN Zhaopeng(Qingdao Meteorological Bureau,Qingdao 266003,China;Heze Meteorological Bureau,Heze 274000,China)

机构地区：[1]青岛市气象局,山东青岛266003 [2]菏泽市气象局,山东菏泽274000

出　　处：《海洋气象学报》2024年第3期87-94,共8页Journal of Marine Meteorology

基　　金：山东省自然科学基金项目(ZR2021MD010,ZR2021MD062,ZR2023MD118);山东省气象局创新团队项目(SDCXTD2023-1);山东省气象局科研项目(2022sdqxm08);淮河流域气象开放研究基金项目(HRM201807);青岛市气象局科研项目(2023qdqxz02)。

摘　　要：利用2007—2022年卫星资料、常规探测资料和ERA5资料,对影响山东的中尺度对流复合体(mesoscale convective complex,MCC)的结构特征及降水分布进行分析。结果表明:(1)MCC多数在傍晚至次日凌晨发展成熟,早晨消亡,生命史较长,平均寿命为7 h,生命史为6~8 h的占88%。根据对流云团的生成源地和移动路径将MCC分为东移型、北上型和原地生成型,其中东移型最多。(2)MCC强降水与最低云顶亮温(也称黑体温度,black body temperature,TBB)和TBB梯度大值区密切相关。东移型MCC 500 hPa中高纬环流平直,强降水位于MCC的西—西北侧;北上型MCC环流为经向型,最强降水位于MCC的南—西南侧;原地生成型MCC引导气流弱,降水分布零散,范围小,分布在TBB梯度大值区。(3)东移型MCC和北上型MCC伴随冷暖空气交汇造成锋生,暖平流区中锋生最强区域通常对应降水大值中心,锋消区内无显著降水;而原地生成型MCC冷平流弱,强降水主要位于暖区一侧。The structural characteristics and precipitation differences of mesoscale convective complexes(MCCs)affecting Shandong are analyzed using satellite data,routine observations and ERA5(ECMWF Reanalysis v5)data from 2007 to 2022.The results are listed below.(1)Most MCCs,developing and maturing from the evening to the early morning of the next day and then disappearing in the morning,have a long life history with an average lifespan of 7 h and 88%of 6-8 h.Based on the generation sources and moving paths of convective cloud clusters,MCCs can be classified into three types,namely eastward type,northward type and in-situ generating type,with the eastward type being the most frequent.(2)The strong precipitation in MCCs is closely related to the minimum cloud top brightness temperature(also referred to as black body temperature,TBB)and the areas of large TBB gradient.The 500-hPa circulation of the eastward type in the mid-high latitudes is flat,and the strong precipitation is located on the west-northwest side of MCC;the circulation of the northward type is meridional,with the strongest precipitation located on the south-southwest side of MCC;the in-situ generating type has weak guiding airflow,scattered distribution and small range of precipitation and the precipitation is distributed in the areas of large TBB gradient.(3)The strong convergence of cold and warm air in the eastward type and northward type leads to frontogenesis,the strongest area of frontogenesis in the warm advection zone usually corresponds to the center of large precipitation,and there is no significant precipitation in the frontolysis zone.However,the cold advection of the in-situ generating type is weak,and the strong precipitation is mainly located on the warm side.

关 键 词：中尺度对流复合体(MCC) 短时强降水 结构差异 锋生函数 

分 类 号：P458.2[天文地球—大气科学及气象学]