Simulations of the Quasi-Biennial Oscillation and its Effect on Stratospheric H2O, CH4, and Age of Air with an Interactive Two-Dimensional Model.

摘要

A zonally averaged photochemical dynamical model of the middle atmosphere is used to simulate the quasi-biennial oscillation (QBO) and its effect on the distributions of stratospheric H2O, CH4, and age of air. Changes in planetary wave amplitudes of 25% cause 2 3 month changes in QBO period. Comparable changes in prescribed tropical heating have a smaller effect on the QBO period. The response of tropical upwelling, and QBO period, to changes in extratropical forcing depends on the magnitude and location of the imposed changes. In the Southern Hemisphere, where the planetary wave forcing is smaller than in the Northern Hemisphere, increased forcing produces stronger equatorial upwelling and a longer QBO period. In the Northern Hemisphere, increased forcing produces weaker upwelling and a shorter QBO period due to the larger amplitude waves becoming saturated.