摘要
试图建立一个简单海气耦合模式，其中大气垂直分为两层，为－β平面近似线性模式。在非绝热加热项中包含了对流凝结潜热与大尺度流场之间相互作用的ＣＩＳＫ机制以及蒸发、感热与扰动风场之间的反馈机制，并考虑了东风区与西风区的不同。由于只研究大气的平均纬向运动，故模式大气中仅含有Ｋｅｌｖｉｎ波。海洋模式为一约化重力模式，只保留了Ｒｏｓｓｂｙ波。对这一海气耦合模式进行特征波动分析，发现考虑海气耦合效应并不影响大气波动的性质，在东风区大气Ｋｅｌｖｉｎ波仍然增幅和东传；在西风区大气Ｋｅｌｖｉｎ波振幅衰减。但海气耦合效应却使得大气Ｋｅｌｖｉｎ波的传播速度减慢，周期增大。当考虑海气耦合效应时，海洋Ｒｏｓｓｂｙ波的稳定性质发生变化，由原来的中性波动变为非中性波动。在西风区，波数小于某临界波数的长Ｒｏｓｓｂｙ波振幅增大，而短的Ｒｏｓｓｂｙ波振幅衰减。在东风区结论相反。对海气耦合模式中波动的分析，为数值模拟西太平洋暖池的形成及其对大气扰动的影响建立了理论基础。
In this paper a simple coupled oceanatmosphere model is developed. The atmosphere is a βplane approximation model which is divided into two layers vertically. The interaction between convective condensational heating and large scale flow as well as the feedback among evaporation, sensible heating and perturbation wind is considered in the diabatic heating term. Also, the difference between the easterly and westerly in the parameterization of evaporation and sensible heating is taken into consideration. As we only consider the zonal motion of the tropical atmosphere, only the Kelvin wave is included in the model atmosphere. The ocean is a reducedgravity model in which only the Rossby wave is kept. Through the eigenmode analysis, it is shown that the coupling of ocean and atmosphere does not change the stability characteristics of the atmospheric Kelvin wave. In the easterly region, the atmospheric Kelvin wave still amplifies and propagates eastwards. In the westerly region, the atmospheric Kelvin wave damps. But the coupling slows down the speed of atmospheric Kelvin wave and enlarges its period. However, the coupling makes the neutral oceanic Rossby wave become a nonneutral one. In the westerly region, the long Rossby wave whose wave number is smaller than a critical value amplifies, but the short Rossby wave damps. In the easterly region the conclusion is opposite. The eignmode analysis of wave characteristics provides the foundation for the numerical simulation later.
出处
《青岛海洋大学学报（自然科学版）》
CSCD
1998年第3期353-362,共10页
Journal of Ocean University of Qingdao
关键词
西太平洋
暖池
海气耦合模式
形成机制
大气扰动
west Pacific warm pool
simple coupled oceanatmosphere model
atmospheric Kelvin wave
oceanic Rossby wave
oceanatmosphere coupled effect
