论文标题
在垂直剪切大气中的强烈非线性重力波上，第一部分：折射波的光谱稳定性
On strongly nonlinear gravity waves in a vertically sheared atmosphere, Part I: Spectral stability of the refracted wave
论文作者
论文摘要
我们研究了强烈的非线性固定重力波，由于水平背景风的垂直剪切层而导致折射。波的速度幅度与背景流的数量级相同，因此自诱导的平均流量会改变调制特性到领先顺序。在这项理论研究中，我们表明，这种折射波的稳定性取决于剪切上方和下方的每个单个层的经典调制稳定性标准。此外，稳定性是由新的不稳定性标准来调节的，该标准在平均流水平风和波的幅度上提供边界。不稳定的必要条件是，上层的平均水平风比下层的风强。
We investigate strongly nonlinear stationary gravity waves which experience refraction due to a thin vertical shear layer of horizontal background wind. The velocity amplitude of the waves is of the same order of magnitude as the background flow and hence the self-induced mean flow alters the modulation properties to leading order. In this theoretical study, we show that the stability of such a refracted wave depends on the classical modulation stability criterion for each individual layer, above and below the shearing. Additionally, the stability is conditioned by novel instability criteria providing bounds on the mean-flow horizontal wind and the amplitude of the wave. A necessary condition for instability is that the mean-flow horizontal wind in the upper layer is stronger than the wind in the lower layer.
