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原始方程线性模型允许两类波(罗斯贝波和重力波)的解,这两类波的振幅由初始条件确定。大尺度的罗斯贝波在结构和相速度方面类似于大气中观测到的瞬态波运动。而另一部分解大尺度的重力波所具有的频率超过了观测到的大尺度气流的频率一个多数量级。于是,象这样大尺度高频重力波在大气中不存在,或者至少它们具有非常小的振幅。另一方面,在大尺度气流的模式中,基于非线性方程,如果初始资料不满足风场和质量场之间的弱平衡,则大振幅高频振荡就建立起来了。象这样虚假的高频重力波振荡叫作气象噪音(Hinkelmann1951)。 用所建立的时间和(或)空间耗散模式,这些虚假高频振荡在一定周期的时间之后就消亡了。其长度取决于初始资料不准确的程度和取决于耗散的强度。在多数情况中,阻尼周期的长度或许小于24小时,至少对于较高频是如此,在这期间,振荡损害了质量场,特别是散度场的计算,从而损害了垂直运动和降雨量的计算。
The linear equation of the original equation allows the solution of two types of waves (Rossby waves and gravity waves) whose amplitude is determined by the initial conditions. Large-scale Rossby waves are similar in structure and phase velocity to the observed transient wave motion in the atmosphere. While the other part of the solution to large-scale gravity waves has a frequency that is more than one order of magnitude larger than the observed large-scale airflow. Thus, large-scale high-frequency gravitational waves like this do not exist in the atmosphere, or at least they have very small amplitudes. On the other hand, in the large-scale airflow model, based on the nonlinear equations, large-amplitude high-frequency oscillations are established if the initial data do not satisfy the weak balance between wind and mass fields. Such a false high-frequency gravitational wave oscillation is called meteorological noise (Hinkelmann 1951). With the established time and / or space dissipation modes, these false high-frequency oscillations disappear after a certain period of time. Its length depends on the inaccuracy of the initial data and on the strength of dissipation. In most cases, the length of the damping period may be less than 24 hours, at least for higher frequencies, during which the oscillation impairs the calculation of the mass field, in particular the divergence field, thereby compromising the calculation of vertical movement and rainfall .