台风“威马逊”和“海鸥”与大尺度环流相互作用对云南暴雨落区的影响  

Impact of the Interaction of Typhoon Rammasun and Typhoon Kalmaegi and Large-scale Circulation on Rainstorm Area in Yunnan

作　　者：杨素雨[1] 张秀年[1] 邹阳 何钰[1] YANG Suyu;ZHANG Xiunian;ZOU Yang;HE Yu(Yunnan Meteorological Observatory,Kunming 650034,China;Kunming Meteorological Observatory,Kunming 650500,China)

机构地区：[1]云南省气象台,云南昆明650034 [2]昆明市气象局,云南昆明650500

出　　处：《成都信息工程大学学报》2019年第5期552-559,共8页Journal of Chengdu University of Information Technology

基　　金：国家自然科学基金资助项目(41565002);云南省气象局重点资助项目(TQ201701);国家重点研发计划资助项目(2018YFC15 07603);云南省科技厅资助项目(2018BC007、2016RA096)

摘　　要：为揭示西行台风低压与大尺度环流相互作用对云南暴雨落区的影响,采用天气学分析、诊断分析方法,对2014年两次西行台风“威马逊”(1409号)和“海鸥”(1415号)与大尺度环流场的相互作用做对比分析。研究表明:“威马逊”过程期间,副高中心偏西偏北,强度偏强,且稳定少动,使台风低压移动缓慢;西南季风低空急流北界位于20°N,呈东西带状分布,其出口区左侧动力辐合作用及长时间维持,为台风低压补充大量能量和水汽,是使台风低压在陆上维持和再次增强导致暴雨落区位于滇中及以南的重要原因。而“海鸥”过程期间,副高588线西端呈南北向分布,其偏南低空急流左侧动力辐合作用及低层冷空气入侵台风低压东北侧倒槽,斜压有效位能转换为动能,是暴雨落区位于滇中及以东的重要原因。此外,两次过程的暴雨落区位于850 hPa水汽通量大值中心的下游强水汽辐合区附近。In order to reveal the influence of the interaction between the westerly typhoon low pressure and the large-scale circulation on the rainstorm area in Yunnan,using the methods of synoptic analysis and diagnostic analysis,the interaction between two westbound typhoons(Rammasun No.1409,Kalmaegi No.1415)and large-scale circulation in 2014 was compared and analyzed.The results showed that during the period of Rammasun's influence on Yunnan,the cause of the slow movement of typhoon was the center extends westward and partial north,the stronger strength and the stable position of the Subtropical High.The northern boundary of the southwest monsoon low-level jet lied at 20 degrees N,and was east-west zonal distribution.Typhoon low pressure could be maintained and renewed on land because of the dynamic convergence and the continuous transmission of water vapor and energy on the left side of the southwest low-level jet exit.The above analyses were important reasons for the east-west distribution of rainbelt in the middle and south of Yunnan.However,as the influence of Kalmaegi in Yunnan,the west end of the 588 line of the Subtropical High showed a north-south distribution pattern and the middle east of Yunnan was located on the left of the southward low jet.In addition,the low-level cold air invaded the northeast side of the typhoon low pressure inverted trough,leading to the conversion of baroclinic effective potential energy into kinetic energy.The above analyses were important reasons for the eastwest distribution of rainbelt in the central and east of Yunnan.Finally,the rainstorm falling areas of the two process were distributed along the downstream area of the 850 hPa water vapor flux center,and were located near the 850 hPa strong water convergence center.

关 键 词：气象学 天气预报 台风低压 低空急流 暴雨落区 大尺度环流 

分 类 号：P458.124[天文地球—大气科学及气象学]