一类描述大气中重力孤立波的新模型

从两层流体浅水波方程出发，运用尺度分析与扰动方法，建立了一类新的模型(mKdV-BO模型)来描述大气中的重力孤立波。前人建立的KdV模型和BO模型适合描述经向和纬向扰动较弱时重力孤立波的生成和演化，而该模型的非线性更强，适合描述经向、纬向扰动较强时重力孤立波的生成与演化。通过运用试探函数法获得了模型的代数孤波解，并分析了孤立波的生成条件与传播速度。新模型的建立对于进一步解释大气中列队雷雨阵的形成机制，探讨大气中的强对流天气如飑线的形成等具有重要意义。 关键词：重力孤立波；试探函数法；列队雷雨阵

A Kind of New Model for Describing the Gravity Solitary Wave in the Atmosphere

This paper embarks from the two-layer fluid shallow wave equation. With the help of multiscale analysis and perturbation expansions method, we build a kind of new model describing the gravity solitary wave in the atmosphere. Compared with former models, this model describes the formation and evolution of the gravity solitary wave appropriately when the disturbance enhances in both meridional and zonal direction. Through using the trial function method, we obtain algebraic solitary wave solution of the model and analyze the generating condition and propagation speed of the solitary wave. The establishment of the new model has a great effect on further explanation of the formation mechanism of the squall line and rank thunderstorm phenomenon in the atmosphere.