Wave-CISK、蒸发-风反馈和低频振荡

Wave-CISK, Evaporation-wind. Feedback and Low Frequency Oscillation

本文利用一个包含有Wave-CISK和蒸发-风反馈机制的斜压半地转模式来讨论低纬大气运动,其中引入了反映CISK机制的无量纲对流凝结加热参数η和反映蒸发-风反馈机制的无量纲参数α_0,求得了η=0情况下的解析解及η≠0情况下的一级近似解,对η≠0情况下向东传播的类似于低频振荡的波动进行了讨论,从理论上指出了蒸发及非均匀加热对低频振荡的维持所起的重要作用.

A semi-geostraphic model which includes wave-CISK and evaporation-wind feedback is used to discuss LFO (Low Frequency Oscillation) in the tropical atmosphere . Two non-dimensionals η and α0 are used to represent CISK and evaporation-wind feedback mechanisms, repectively. An analytic solution is obtained for η = 0 and an approxiamte solution is also obtianed for η≠0. In this paper, we discuss mainly the eastward LFO and point out that evaporation and horizontal nonuniform heating are necessary to exciting and maintaining LFO . We also point out the important role in monsoon area for LFO .