MULTIPLE FLOW EQUILIBRIA IN THE TROPICAL CIRCULA-TION AND MONSOON

The aim of this paper is to examine whether an axisymmetric tropical model with thermal driving and orographic forcing can produce multiple equilibria in relation to the monsoon circulation over South Asia. The model is an equivalent barotropic balanced equatorial β-plane model. It shows that there may exist mul-tiple flow equilibria for a given driving, of which two may be stable: one corresponds to the summer monsoon, and the other to the winter monsoon circulation. The transition between them is also discussed.