“达维”台风强度突变的诊断分析  

The Diagnostic Analysis of Intensity Sudden Change of Typhoon Damrey

作　　者：袁小超[1] 谭季青[1] 

机构地区：[1]浙江大学地球科学系,杭州310027

出　　处：《科技通报》2011年第4期489-494,502,共7页Bulletin of Science and Technology

基　　金：国家自然科学基金项目资助(40875091)

摘　　要：利用1°×1°NCEP再分析资料,对台风"达维"(0518)强度突变进行分析,发现副高西伸加强引起的台风气旋性环流的加强、青藏高压热力作用引起的台风区域位势不稳定的增强、台风高空外流气流的加强及台风东侧高空急流的形成并与台风低层偏南风急流的耦合有利于台风的突然加强,青藏高压对台风区域中低层热力作用的减弱、高空外流气流的减弱及台风东侧高空急流的消失有利于台风的突然减弱;对台风突然加强和突然减弱时的涡度收支进行诊断分析,得出了一些有意义的结果;同时发现"达维"中低层区域平均的总温度散度净辐合值对其突然加强和突然减弱有着预示作用,在对流层中低层环境场突然的能量注入为其突然加强提供条件,随后净辐合值的突然减小也预示台风的迅速减弱。By using data of NCEP-NCAR 1°×1° reanalysis data,we carried out a diagnostic study to the intensity sudden change of Tropical cyclone Damrey （0518）. Results showed＇ that：strengthened cyclonic circulation of typhoon caused by the strengthening of Westward extension of the subtropical high, enhanced potential instability in the typhoon region due to the heating role of Tibet high, the strengthening of the outflow of air at upper-level and the formation of Upper-level jet at the east of the typhoon and its coupled with the Low-level southerly jet which are contribute to the abrupt intensifi- cation of the typhoon, the weakening of thermal effect of the Tibet High on the typhoon region, the weakening of the out- flow of air at upper-level and the vanishing of the Upper-level jet at east side of typhoon are advantageous to the sudden weak of typhoon; also carry out a diagnostic study on vorticity budget at the sudden intensification and sudden weaken time and obtain some significant results; low-level average net convergence field existed during the typhoon life span, Damrey suddenly intensification when the convergence suddenly increased,after that,the convergence suddenly decreased and after 6h Damrey suddenly weaken too.

关 键 词：台风 强度突变 诊断分析 

分 类 号：P444[天文地球—大气科学及气象学]