正压大气模式下具有β效应与地形效应的Rossby孤立波

Solitary Rossby waves with beta effect and topography effect in a barotropic atmospheric model

正压大气模式下,采用摄动方法和时空伸长变换推导了具有β效应、地形效应和耗散的mKdV-Burgers方程,得到Rossby孤立波振幅的演变满足带有β效应,地形与耗散的mKdV-Burgersm方程的结论.说明β效应、地形效应是诱导Rossby孤立波的重要因素.

Rossby waves are the most important waves in the atmosphere and ocean,and are intrinsic to the large-scale systems in fluids.The theory and observation show that their basic characteristic satisfy the quasi-geostrophic and quasi-static equilibrium approximations.In barotropic fluid,discussed long waves in a homogeneous atmosphere and obtained the Korteweg-de Vries（KdV）equation,but the analysis was limited to the case where the velocity shear was small compared with a basic uniform zonal motion and they gave no insight pertaining to the kinds of stream-line-flow patterns accompanying these waves.An inhomogeneous modified Korteweg-de Vried（mKdV）-Burgers equation including beta effect,topography and dissipation is derived by employing the perturbation method in a barotropic atmospheric model,the inhomogeneous mKdV-Burgers equation describing the evolution of the amplitude of solitary Rossby waves as the change of Rossby parameter β（y） with latitudeytopographic forcing and dissipation is obtained.