CISK AND EVAPORATION-WIND FEEDBACK MECHANISM AND 30-60 DAY OSCILLATIONS IN THE TROPICAL ATMOSPHERE

A baroclinic semi-geostrophic model with Evaporation-Wind Feedback Mechanism (EWFM) and CISK is established,two nondimensional parameters a and η are introduced to represent EWFM and CISK,respectively.The analytic solutions are obtained.Dynamics analyses and model atmosphere calculations further demonstrate that EWFM and CISK are very important physical processes in leading to the low-frequency oscillations in the tropics.