Antarctic measurements of ozone by SAGE II in the spring of 1985, 1986, and 1987



Vertical profiles of ozone obtained by the Stratospheric Aerosol and Gas Experiment II (SAGE II) inside the southern polar vortex indicate ozone depletion increased dramatically in October 1987 when compared to the previous worst year, 1985. Minimum observed October concentrations dropped from about 4.E+11 to 1.E+11 (molecules/cm³) at 16 km, while minimum total column sums (above 100 mb) dropped by 15%. The top altitude of the depletion region shows a slight correlation with depletion severity in October, being located at 22-23 km in 1985, 22 km in 1986, and consistently at 23 km in 1987. A less severe downward trend in ozone is observed in September. Vertical profiles of ozone within the vortex are presented for September and October 1987 and compared to 1985 and 1986.