Oxford MIPAS Antarctic O3

The plot above shows the average ozone column above the 100 mb pressure (approx 15km altitude) in the Antarctic Vortex, while the plot below shows the average for the region polewards of the 65degS latitude circle, as determined from the Oxford retrievals of data from the MIPAS instrument on the ESA Envisat satellite.

The Vortex region is (crudely) estimated by taking the profiles with the mininum temperature at 30 mb corresponding to an area equivalent to that polewards of 80deg S (about 16% of the total area averaged in the lower plot).

The "ozone hole" typically develops throughout August and September, dispersing some time during October as the polar vortex breaks down (2002 - shown in pink - was an unusual year in that the normally-stable polar vortex split in two allowing the ozone-rich air from lower latitudes to enter the polar region).