大尺度海温异常对热带大气Kelvin波的影响

ON THE EFFECT OF LARGE SCALE SSTA UPON THE TROPICAL ATMOSPHERIC KELVIN WAVE

本文用一个简单的斜压两层模式，在热力学方程中只考虑牛顿冷却和感热加热，从理论上分析了大尺度海温异常时感热加热对热带大气Kelvin波的影响。研究发现，牛顿冷却使大气Kelvin波振幅衰减，并使波速减慢;感热加热可使得Kelvin波波速加快；当海气温差超过某一临界值时，波动趋于不稳定。

A simple baroclinic two-layer model is employed in this paper, in which only Newtonian cooling and sensible heating are taken into account in the thermal equation. The effect of sensible heating due to large scale SSTA upon the tropical atmospheric Kelvin wave is analyzed. It is found that the Newtonian cooling makes the amplitude of the Kelvin wave reduce and slows down the wave speed.When the SST increases anomaly, the Kelvin wave speed becomes larger. When the temperature difference between air and sea is greater than a critical value,the wave becomes unstable.