大气科学2013，Vol.37Issue(1)：81-90,10.DOI:10.3878/j.issn.1006-9895.2012.11115
台风Nari(0116)登陆台湾过程中结构强度变化的诊断分析
Diagnostic Analysis on Nari (0116) Structure and Intensity Changes during Its Landfall Process on Taiwan Island
摘要
Abstract
Diagnostic analysis was performed on Typhoon Nari (2001), which exhibited abnormal structural and intensity changes when crossing Taiwan Island, on the basis of the 2001 Tropical Cyclone Yearbook compiled by the Chinese Meteorological Administration, the United States National Center for Environmental Prediction (NCEP) final (FNL) 1°X 1° global grid data, and temperature of black body (TBB) data from the Japan Meteorological Agency. The following results are reported: (1) Nari's cloud structure changed from circular to semicircular with convective clouds developing in the western area and dissipating in the eastern area of typhoon circulation during its landfall process and maintained such an asymmetric structure over the island. (2) When crossing the island, a lower-layer jet (LLJ) stream in Nari's western circulation strengthened and extended counterclockwise from north to south. The increase in angular momentum of the tangential wind was favorable for strengthening vortex circulation. In addition, the water vapor flux convergence near the LLJ and the strong positive vorticity on the left of the LLJ axis helped to maintain the cyclonic vortex. (3) Taiwan topography, including the Taiwan Strait, had a pronounced effect on the structure and intensity of Nari. The windward slope-forced lifting intensified ascending air flow in Nari's western circulation; however, the sinking on the leeward side restrained the convection in its eastern circulation. These factors were primarily responsible for the formation of Nari's semicircular asymmetric structure. Moreover, the channel effect of Taiwan Strait benefited the strengthening and stretching of the LLJ stream in Nari's western periphery. (4) A diagnosis of kinetic energy budgets revealed that the kinetic energy of Nari was generated from the solenoid effect. In addition, horizontal convergence movement provided kinetic energy for Typhoon Nari during its landfall process.关键词
热带气旋/台湾地形/海峡效应/结构强度变化Key words
Tropical cyclone/ Taiwan terrain/ Channel effect/ Intensity and structure change分类
天文与地球科学引用本文复制引用
胡姝,李英,魏娜..台风Nari(0116)登陆台湾过程中结构强度变化的诊断分析[J].大气科学,2013,37(1):81-90,10.基金项目
国家重点基础研究发展规划项目2009CB421504,国家自然科学基金项目40975032、41275066,公益性行业(气象)科研专项GYHY200706020 （气象）
