A Preliminary Study of the Dynamics of Transient, Planetary Waves in the Atmosphere
A Preliminary Study of the Dynamics of Transient, Planetary Waves in the Atmosphere
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大气中瞬态行星波动力学的初步研究
DOI：
10.1111/j.2153-3490.1961.tb00093.x
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发表时间：
1961
期刊：
影响因子：
2
通讯作者：
A. Wiin
中科院分区：
文献类型：
--
作者：
A. Wiin
最近对大气中行星波的研究表明，对于其尺度与地球半径相当的运动，涡度方程具有准静态特征。这些试探性的结果被作为工作假设，并对在工作假设的基础上建立的大气模式中可能存在的波的稳定性和结构进行了初步研究。结果表明，假定的定常形式的涡量方程起到了滤波器的作用，在双参数情况下消除了线性化方程的解中的Rossby波。然后，找到并研究了三参数模型的线性化形式的波解。主要结果是，只有缓慢移动的波是可能的，对于足够大的垂直风切变，将出现不稳定的波解。分析了一种考虑涡度水平平流的修正形式，结果表明存在一个最不稳定的波长。建立了一个可用于行星波研究的预报模式。由于该模型只适用于行星尺度，它可以用来研究行星尺度和更小尺度之间的非线性相互作用的重要性。DOI：10.1111/j.2153-3490.1961.tb00093.x
Recent studies of the planetary waves in the atmosphere have suggested that the vorticity equation assumes a quasi-stationary character for motions whose scale is comparable to the radius of the earth. These tentative results are adopted as a working hypothesis, and a preliminary study is made of the stability and structure of the waves which are possible in an atmospheric model which is formulated on the basis of the working hypothesis. It is shown that the assumed stationary form of the vorticity equation acts as a filter which eliminates the Rossby type waves from the solution of the linearized equations in the two-parameter case. The wave-solutions in a linearized form of a three-parameter model are next found and investigated. The major results are that only slowly moving waves are possible and that unstable wave-solutions will appear for sufficiently large vertical wind-shears. A modified form of the model in which horizontal advection of vorticity is also included is analyzed, and it is shown that a wave-length of maximum instability occurs. A prediction model which can be used in studies of the planetary waves is formulated. Since the model will apply to planetary scales only, it can be used to study the importance of non-linear interactions between the planetary scales and smaller scales. DOI: 10.1111/j.2153-3490.1961.tb00093.x