“黄蜂”登陆过程中路径变化的可能成因分析  

A POSSIBLE REASON OF TRACK VARIATION OF VONGFONG DURING LANDING

作　　者：陈子通[1] 

机构地区：[1]中国气象局广州热带海洋气象研究所,广东广州510080

出　　处：《热带气象学报》2004年第6期625-632,共8页Journal of Tropical Meteorology

基　　金：科技部社会公益研究专项(2001DIA20026-01)"华南台风登陆过程机理和预报技术研究"资助

摘　　要：借助时间分辨率为6分钟的新一代多普勒雷达回波、卫星资料和常规观测资料对“黄蜂”在登陆过程中路径变化的情况进行了分析。主要是从雷达回波和卫星观测到的强水汽对流相对于风暴中心的分布,并运用包含非绝热加热作用的全型涡度方程,讨论对流潜热导致的涡度增加及涡度平流对风暴移速、移向的影响作用,解释了登陆过程中三个阶段路径变化的可能原因。认为:(1)登陆前阶段,由于强水汽对流在中心的东北到北侧,造成向西北方向的正涡度平流,从而这一阶段有相对较大向西移动分量,并且移速较快;(2)登陆阶段,前3小时,强水汽对流主要位于中心的西侧,因而有向南移动分量,后3小时,强水汽对流主要位于中心的南侧,因而有向东的移动分量,所以这个阶段风暴减速运动,并且前3小时继续向西北方向移动,而后3小时转为偏北方向;(3)登陆后阶段,由于风暴迅速减弱,强对流仅在东南-西北向区域短暂维持,风暴有向西北前方强对流区加速的趋向运动,因而在登陆后,“黄蜂”表现为西北向的加速运动。Track variation of severe tropical storm “Vongfong” is analysed by using radar images of 6 min interval, satellite and conventional data during landing. With the distribution of moisture convection concerning the storm center, which are observed from radar and satellite images, and complete form of vertical vorticity equation containing diabatic heating, the influence of vorticity increasing and vorticity advection caused by moisture convection upon the track of storm is discussed, and a possible reason of track variation during landing is explained. It is considered that the reason of high speed and more westering component moving was the northwestward vorticity advection due to strong moisture convection locating in the northeast to north region of the storm center during the pre-landing period, and the reason of low speed and northwestwards moving in the first 3 hours and northwards in the late 3 hours was the strong moisture convection locating in the west region in the first 3 hours and locating in the south region in the late 3 hours during the landing period, and the reason of high speed and northwestwards moving was the moving tendency to the strong convection locating in northwest region because of the storm rapidly weakening and the strong convection briefly maintaining only in the southeast to northwest region during the late landing period.

关 键 词：热带气旋 登陆 路径 

分 类 号：P444[天文地球—大气科学及气象学]