Abstract: Tropical cyclone is divided into inner and outer regions in which the scale of time-space and physical quantity are all different. Making use of the scale analysis and perturbation method on the two regions of tropical cyclone the governing equations of baroclinic models are obtained respectively. The inner region is governed by cyclic wind while the outer region by gradient wind, but the governing equations are similar, they can be solved analytically by the same equations. The obtained structure of the stream and pressure fields consistents approximately with observations.

Key words: tropical cyclone, perturbation method, dynamic structure

摘要： 将热带气旋分为内外2个区，2个区的时间、空间及物理量有不同的尺度，应用尺度分析和摄动法到热带气旋的2个区域，分别求得在2个区域的控制方程，其中内区受旋转风和一个演变方程制约，外区受梯度风和另一个演变方程制约。内外区的演变方程形式上相似，可统一求解，并解析地求得了2个区域的流场和气压场，得到的解能反映热带气旋结构的一般特征。

关键词: 热带气旋, 摄动法, 动力学结构