地形对涡量传播和台风切向风速变化的参数敏感性  

THE TOPOGRAPHIC PARAMETER SENSITIVITY TO VORTICITY PROPAGATION AND TYPHOON TANGENTIAL VELOCITY CHANGES

作　　者：余锦华[1] 

机构地区：[1]南京信息工程大学,江苏南京210044

出　　处：《热带气象学报》2004年第6期679-688,共10页Journal of Tropical Meteorology

基　　金：国家科学技术部专项项目(2001DIA20026);国家自然科学基金项目(49975013)资助

摘　　要：设计了一个高分辨率的浅水模式,以研究地形参数和纬向基流在涡旋Rossby波传播和台风切向风速变化中的作用。结果表明,无纬向基流条件下,岛屿地形的水平尺度对涡旋Rossby波传播的影响表现在:随地形水平方向尺度的增大,扰动涡度场环绕地形顺时针方向旋转的趋势增强,局域风速增幅减小,增强了平均风速的减弱。纬向东风基流条件下,热带气旋的局域风速及其平均切向风速的演变受台风与地形间距的改变以及地形作用时间长短的影响:当台风逐渐靠近地形时,局域风速增幅增强,平均风速逐渐减小;当台风逐渐远离地形时,出现相反的变化。A high resolution shallow-water model is designed to study the roles which the topographical parameter and latitudinal basic flow play in the propagation of vortex Rossby waves and typhoon tangential velocity changes. With no latitudinal flow, the horizontal scale effects of island rerrain on the vortex Rossby waves propagation show that the disturbance vorticity follows a clockwise island-circulating path more significantly, the local maximum wind speed amplitude reduces more sharply, the maximum mean azimuthally tangential wind spins down more substantially, when the topographic horizontal scale augments. With the latitudinal basic flow, the evolution of local wind and mean velocity are affected by the distance changes between TC and the terrain and the time length of topographic action: the local wind amplitude intensifies and the mean velocity diminishes while the distance is shortening; the opposite is true while TC is away from the terrain gradually.

关 键 词：地形参数 涡旋ROSSBY波 台风切向风速 

分 类 号：P444[天文地球—大气科学及气象学]