Dynamic and chemical drivers of the Antarctic ozone hole: A multiple regression analysis of QBO and CFCs

This study explores how stratospheric dynamics and chemistry, particularly the Quasi-Biennial Oscillation (QBO) and chlorofluorocarbons (CFCs), influence Antarctic total column ozone (TCO) and ozone hole area (OHA). By applying multiple linear regression analysis to September OHA data (1979–2024), using QBO zonal wind across 14 vertical levels and multi-species CFC data, we find that QBO vertical structure significantly improves the model's explanatory power, especially post 2005. Residual analysis of the regression reveals that before 2000, CFCs related chemical depletion was the dominant factor controlling OHA, whereas after 2000, dynamic influences from the QBO became more prominent. Including CFCs, the Antarctic Oscillation (AAO), El Niño Southern Oscillation (ENSO) indices, and total solar irradiance (TSI) boosts the model's variance explanation to over 91%. Spatial analysis reveals pronounced regional differences in model performance, with higher skill in the Atlantic-Indian sector and lower predictability in the Pacific sector where nonlinear dynamics likely play a larger role. Our findings highlight the critical role of vertically resolved dynamical predictors and chemical-dynamic coupling in understanding Antarctic ozone variability.​