Inter-annual variation of the Antarctic ozone hole and its impact of Southern Hemisphere climate

Southern Hemisphere (SH) climate change in the past has been attributed to the combined effect of greenhouse gas increase and Antarctic ozone depletion. Recent studies have shown that the latter has played at least a comparable role to the former in austral summer. Here we present that the Antarctic ozone hole has affected not only the longterm trend but also the intraseasonal variability of the SH surface climate. A significant negative correlation is found between the September ozone concentration and the October Southern Annular Mode index, hence resulting in systematic variations in precipitation and surface temperature throughout the SH. This time lagged relationship is comparable to and independent of that associated with El Nino Southern Oscillation, suggesting that SH seasonal forecasts could be improved by considering Antarctic lower stratospheric variability. Possible dynamical processes associated with downward coupling are also discussed in the context of quasi-geostropic zonal mean dynamics.