【摘要】 本文用一个一维线性的二层模式,分析了地转气流中重力惯性内波的动力学性质。讨论了重力惯性内波的不稳定性、相速度和群速度后,指出: 1)当地转风速大于重力内波波速时,某些尺度的重力惯性内波可以产生不稳定性,这种不稳定性可以用来解释某些中系统的发展。 2)某些波长的重力惯性内波,它的群速度可以大于相速度;因此在某一地区有中系统发展时,它的能量可以很快地传到下游,而在某下游产生新的系统。更多还原

【Abstract】 In this paper, the instability, phase velocity and group velocity of the gravitational waves in a geostrophic currents are analysed by using a two layer model. The conclusions reached are that: 1. When the Froude number is greater than unit, the gravitational waves of some wave lengths will become unstable. This instability may be used to explain the development of some meso-scale systems. 2. The group velocity of the gravitational waves can exceed its phase velocity. Therefore, when a meso-scale system is developed in some regions, its energy can travel faster downwind than the phase velocity, therefore a new wave may be formed in the front of the old one.更多还原