Sensitivity of the Southern Hemisphere Semiannual Oscillation in surface pressure to changes in surface boundary conditions

Abstract

The Melbourne University General Circulation Model has been used to simulate the climate of the Southern Hemisphere and its portrayal of the Semiannual Oscillation (SAO) in surface pressure has been assessed. The model is shown to underestimate the amplitude of the SAO slightly but simulate its general structure quite well. To assess the relative importance of various factors in determining the characteristics of the SAO, we perform several anomaly experiments. In particular, we conduct an experiment where the Antarctic topography is leveled, an experiment where the sea ice surrounding the Antarctic continent is removed and also an experiment that combines the two changes. The impact on the ..