Scientists at the German Aerospace Center (DLR) analysed data from the Global Ozone Monitoring Experiment 2 (GOME-2) instrument on the satellite. According to scientists, some unusual meteorological conditions this year drove extensive thinning over the South Atlantic and South America and a build-up of ozone over Australia.
this year, the layer thinned down to 220 Dobson units, a measure of atmospheric ozone (where, the global average of the ozone layer is 300 Dobson units). However, the thinning this year has been well short of last year's record hole, which at times was bigger than North America. Link