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Changes in Total Column Dobson Ozone measurements made at the Amundsen Scott South Pole Station (AMS) during 15-31 October. The y-axis shows ozone change (percent) from the pre-ozone hole reference level of 300 DU (averaged over 1962-1978). The dots are column ozone averages for the 15-31 October period measured from 1962 to 2017. The thin line is the Loess-smoother fit to the data. The record-long average thickness of the ozone layer over the South Pole is 260 DU (245 DU after 1979). If the ozone layer was compressed to a layer of pure ozone at the sea level, the thickness would be 2.6 (2.45) millimeters thick -- about 2 and half stacked dimes. If the entire atmosphere were to be also compressed, it would be about 8 kilometers (5 miles) thick.