j@1040: Minimum of the mean ozone column in the polar vortex (top) for j@1040: March in the Arctic (below) for October in the Antarctic j@1040: derived from the ozone climatology of Bodeker Scientific and OMI j@1040: satellite data. Open symbols for years in which at the time j@1040: the polar vortex was already broken down. After Müller et al. (2008) [#]_ j@1040: j@1040: j@1040: .. [#] Müller, R. et al., Simple measures of ozone depletion in j@1040: the polar stratosphere, Atmos. Chem. Phys., 8, 251-264, 2008, j@1040: https://doi.org/10.5194/acp-8-251-2008. j@1040: j@1040: