The SH mid-latitude atmospheric circulation in a coupled GCM, and its fluctuations at different time scales

The LMD GCM constitutes the atmospheric component of the IPSL (Institut Pierre Simon Laplace). It has been integrated for long periods of several centuries,both in the conditions of the present climate, and in the conditions of an increasing CO2 content (Fairhead et al; Dufresne et al) The purpose of the paper is to present a general analysis of the model variability at different time scales, for the mid-latitudes of the Southern Hemisphere. This variability is described first by the changes in the SST. But we will also describe the associated changes of the atmospheric circulation. Part of this mid-latitude circulation may be characterized by the statistical determination of weather regimes. This method has been popular to describe the atmospheric circulation in the Northern Hemisphere, and its possible changes. It will be repeated here for the Southern Hemisphere.