The Role of Meridional Cell in the Response of Atmosphere to the SSTA Forcing

A simple model is developed including the effect of the meriodional cell. The global zonal mean fields are calculated from the data of EWMFC of 1982. A series of numerical experiments show that when the SSTA forcing locates at equatorial regions, the waves from the SSTA diabatic forcing can propagate towards both hemispheres. But when we consider the effect of Hadley cell, the characteristics of wave propagation have obvious changes in both the spatial phases and amplitudes, and they conform with actual atmospheric anomalies all the more. When the SSTA forcing locates at the northern (or southern) hemisphere, if we don’t consider the Hadley cell effect, the diabatic forcing can not have a strong atmospheric response in the southern (northern) hemisphere. But when the Hadley cell is considered, the waves from the diabatic forcing can propagate towards the other hemisphere. Furthermore, the seasonal effects on atmospheric response to the diabatic forcing are also discussed