Interannual Changes of the Stratospheric Circulation: Relationship to Ozone and Tropospheric Structure

Abstract

Abstract Interannual changes of stratospheric dynamical structure and ozone are explored in observed variations over the Northern Hemisphere during the 1980s and 1990s. Changes of dynamical structure are consistent with a strengthening and weakening of the residual mean circulation of the stratosphere. It varies with the Eliassen–Palm (E–P) flux transmitted upward from the troposphere and, to a lesser degree, with the quasi-biennial oscillation (QBO). These two influences alone account for almost all of the interannual variance of wintertime temperature over the two decades, even during unusually cold winters. Stratospheric changes operating coherently with anomalous forcing of the residual circulation are coupled to changes of tropospheric wave structure. Those changes of dynamical structure share major features with the Arctic Oscillation. Both involve an amplification of the ridge over the North Pacific and an expansion of the North Atlantic storm track. Changes of tropospheric wave structure lead to a...