Antarctic stratospheric warming induced by SST increases

In the present study, we show evidence of significant stratospheric warming over large portions of the Antarctic polar region in winter and spring seasons, with a maximum warming of 7-8o C in September and October, using satellite Microwave Sounding Unit observations for 1979-2006. It is found that this warming is associated with increasing wave activity from the troposphere into the stratosphere, suggesting that the warming is caused by enhanced wave-driven dynamical heating. We show that the Antarctic stratospheric warming has close correlations with sea surface temperature (SST) increases, and that general circulation model simulations forced with observed time-varying SSTs reproduce similar warming trend patterns in the Antarctic stratosphere. These findings suggest that the Antarctic stratospheric warming is likely induced by SST warming. As SST warming continues as a consequence of greenhouse gas increases due to anthropogenic activity, Antarctic stratospheric warming would also continue, which has important implications to the recovery of the Antarctic ozone hole.