摘要
地面摩擦和大尺度流场是影响锋面气旋结构演变的重要因子,本文使用WRF模式并采用湿物理方案,通过理想化试验,综合考虑陆面摩擦、气旋式扰动相对于急流位置和大尺度流场对锋面气旋结构变化的影响.结果表明:当仅考虑单一因子时,气旋式扰动位于急流南侧和辐合流流场有利于气旋形成Shapiro-Keyser(S-K)模型结构.当同时考虑地面摩擦和大尺度辐合时,气旋式扰动位于急流北侧的气旋发展整体向经典的挪威气旋模型转变;扰动位于急流南侧的的气旋发展则整体呈现S-K模型结构,此时辐合流场有利于S-K模型结构出现.当同时考虑地面摩擦和大尺度辐散时,扰动处于急流北侧的气旋呈现挪威气旋模型结构;由于气旋式扰动穿越急流和辐散流场同时有利于暖锋后弯发展以及冷暖锋距离加大和锋消,扰动处于急流南侧的气旋呈现典型S-K气旋模型结构.这个结果解释了在东亚大陆地区辐散场形势下出现的S-K模型结构气旋个例.
Surface friction and the large-scale flow field are considered to be the important factors that affect the evolution of frontal cyclone structure.This paper uses the WRF model with the wet physical scheme to study the influence of the land surface friction,the position of cyclonic disturbance relative to the jet and the large-scale flow field on the evolution of frontal cyclone structure through idealized simulation.The results reveal that when only a single factor is considered,the cyclonic disturbance on the southern side of jet and the confluent flow field are conducive to the formation of the Shapiro-Keyser（S-K）cyclone model.When the land surface friction and large-scale confluent are considered,the cyclonic disturbance on the northern side ofthe jet will make the cyclonic development change to the classical Norwegian model;the disturbance on the southern side of the jet will make the cyclone development present S-K model structure as a whole,and in which case,the confluent flow field tends to be conducive to the formation of S-K model structure.When both the land surface friction and large scale diffluent are considered,the disturbance on the northern side of the jet will make the cyclone present the typical Norwegian model structure,the across-jet of cyclonic disturbance and the diffluent flow field are favorable to the development of warm front bent-back,and the increase in the distance between cold and warm fronts,further leading to front disappear.So the disturbance on the southern side of the jet will make the cyclone exhibit the typical S-K model structure,which explains the S-K model structure cyclone under the diffluent flow field in the East Asia continent.
作者
吴雪剑
费建芳
黄小刚
熊秋芬
程小平
WU XueJian;FEI JianFang;HUANG XiaoGang;XIONG QiuFen;CHENG XiaoPing(College of Meteorology and Oceanography,National University of Defense Technology,Nanjing 211101,China;The 94865 Army of the PLA,Hangzhou 310021,China;China Meteorological Administration Training Center,Beijing 100081,China)
出处
《地球物理学报》
SCIE
EI
CAS
CSCD
北大核心
2018年第8期3149-3159,共11页
Chinese Journal of Geophysics
基金
国家自然科学基金重点项目(41230421)资助
关键词
锋面气旋
陆面摩擦
急流
辐合流场
辐散流场
Frontal cyclone
Land surface friction
Jet
Confluent flow field
Diffluent flow field
