摘要
本文研究了正压大气中一个地形波与三个自由Rossby波的四波准共振动力学特征。由含大地形的准地转正压涡度方程，引入双时间尺度，导得了地用波与自由Rossby波的四波准共振耦合方程组，并求得其低频周期解．由数值计算表明，对于Charney所用地形高度，此解正是准双周振荡。大地形强迫是激发三个自由Rossby波相互输送能量的重要物理机制，使得二个自由Rossby波同时向第3个2波型自由Rossby波输送能量以形成准双周振荡或阻塞。这一结果与观测事实也比较一致。
The feature of four - wave quasi -resonance dynamics among one mountain wave and three free Rossby waves in the barotropic atmosphere is researched. From a quasigeostrophic barotropic vorticity equation including mountain, in terms of two- time scale,the coupled mode equations of four -wave quasi-resonance for a mountain waves and three free Rossby waves are obtained, and its low frequency periodic solution is found. It is shown that the solution is just quasi-two weeks oscillation for the mountain height used by Charney form numerical calculation. Forced action of the large mountain is a important physical mechanism stimulating three free Rossby waves transfer their energy in themselves, and forces two free Rossby waves to simultaneously transfer their energy to the third free Rossby wave for 2 - wavenumber, that the quasi - two weeks oscillation or blocking are formed.The result is comparatively agree with the observation facts also.
出处
《气象科学》
CSCD
北大核心
1994年第2期127-135,共9页
Journal of the Meteorological Sciences
基金
国家自然科学基金
