热带大气和海洋运动的频率差异在海气系统演变中的作用

Characteristics of Sea-Atmosphere Coupling Resolution between Different Frequencies

对热带太平洋地区８５０ｈＰａ纬向风场、海表温度场月平均距平进行了谱分析。结果表明：纬向风距平与海表温度距平的振幅在ＥｌＮｉｏ或ＬａＮｉａ期间同时增长。而在其他期间，波振幅随时间呈相反变化趋势。在ＥｌＮｉｏ或ＬａＮｉａ事件发展期间，纬向风距平的位相角与海表温度距平位相角的差值在９０°左右，而在事件的衰减期间，它们的位相角的差值在０°左右。本文还利用长波近似、海洋对大气加热取局地热力平衡近似时的简单热带海气耦合模式，研究了大气变量和海洋变量位相差随时间变化对海气耦合解的影响。在海气耦合模式中，当大气模式取为非定常时，大气和海洋Ｋｅｌｖｉｎ波之间以及Ｒｏｓｂｙ波之间存在着能量转换，使大气和海洋波振幅呈相反变化趋势。此时，耦合波振幅随位相角差的变化没有共同的增长或衰减区间。大气Ｋｅｌｖｉｎ波与海洋Ｒｏｓｂｙ波或大气Ｒｏｓｂｙ波与海洋Ｋｅｌｖｉｎ波相互作用时，波振幅随位相差的变化存在着相同增长和衰减区间，它们的振幅要么同时增长，要么同时减少。当大气模式取定常时，因为相互作用波之间的位相差是一常数，波振幅随时间无限制增长。本文还在大气模式取为非定常和定常两种情况下，对海气耦合模式进行了数值求解。结果表明，当大气模式取为?

A simple coupled ocean-atmosphere model,in which,long wave approximation is used,the heating of ocean to the atmosphere uses local thermal equilibrium,is used to study the characterstics of ocean-atmosphere coupling resolutions In the coupled model,steady-state and unsteady-state atmosphere model are used The results are following In the unsteady-state atmosphere model,the role of interaction between atmosphere Kelvin waves and ocean Rossby waves and between atmosphere Rossby waves and ocean Kelvin waves is positive feedback,and the role of interaction between atmosphere and ocean Kelvin waves and between atmosphere and ocean Rossby waves is negative feedback The numerical tests show that the numerical solusions are similar to observations in the unsteady-state atmosphere model case In the steady-state atmosphere model case,the ocean-atmosohere interaction of seprate waves between ocean and atmosphere makes the energy of perturbations unlimitedly increase; the numerical solonsions are not similar to observations