Abstract
The Holton-Lindzen (1972) theory of the quasi-biennial oscillation is reevaluated in the light of some recent developments in the theory of wave, mean-flow interaction due to Andrews and Mclntyre (1976a, b). These developments suggest that wave transience should be regarded as the primary cause of the oscillation, in a chronological sense, with wave absorption providing an essential, but chronologically secondary cause. The spontaneous formation and descent of shear zones anticipated in the analytic theory of Part I is here applied to the theory of the oscillation, by extending the numerical calculations of that paper to include equatorial waves of the type observed in the equatorial stratosphere.
Some remarks are also made concerning probable causes of the observed QBO variability.