Weekly and interannual variability of Antarctic PSCs from 1998 to 2005

Data from the POAM III satellite are used to study trends in aerosol extinction at 1018 nm and PSC occurrence. The relationship between stratospheric temperature and aerosol concentration is explored. The relationships between PSC occurrence and the state of atmospheric indices such as ENSO and the QBO are studied. Our results suggest a link between ENSO phase and PSC occurrence in the Antarctic and associated changes in the polar vortex. Weekly and interannual changes in wave patterns are studied to determine what flow conditions are most favorable for Antarctic PSC formation. Comparisons are made to previous studies of stratospheric aerosol.