Plumb三维波作用通量和EP剖面图——对定常波模式输出结果的诊断分析

本文利用Plumb(1985年)所导出的线性、准地转定常波的三维波作用通量和Eliassen-Palm(EP)剖面图,对于一个线性和一个非线性的关于大气定常波的斜压初始方程三维谱模式的若干输出结果进行了诊断分析。分析结果表明,Plumb通量和EP剖面图,不仅可以用来诊断波作用在三维空间的传播、波动与纬向平均气流之间的相互作用,而且也可以用来诊断非线性作用的显著性,在利用它们对于观测资料进行诊断分析时,应当充分注意到非线性作用的影响。

PLUMB WAVE ACTIVITY FLUX AND ELIASSEN-PALM(E-P) CORSS-SECTION: A DIAGNOSTIC ANALYSIS OF THE STATIONARY WAVE MODEL OUTPUT

The low frequency variations are closely related to thestationary waves and, in a sense, they may even be viewed as the timevarying part of the stationary waves themselves. Therefore, an un-derstanding of the maintenance of the stationary waves is a prereq-uisite for a thorough understanding of the low frequency transients.The Eliassen-Palm (EP) cross-section and the three-dimensional waveactivity flux, which was derived by Plumb (1985) for the linear quasi-geostrophic stationary waves in a zonal flow, are used as the diagnos-tics for the output of a three-dimensional spectral model of the linearand nonlinear steady-state baroclinic primitive equations. The resultsshow that the EP cross-section and the wave activity flux are usefulfor diagnosing the vertical and horizontal propagation of the waves andthe significance of the nonlinearity. However, full attention should bepaid to the effect of the nonlinear interaction when diagnostic analysisis made of the observational data.