The recovery of the Antarctic ozone hole

It has now been 30 years since the discovery of the Antarctic ozone hole by Farman, Gardner, and Shanklin (1985). The ozone hole is a massive loss of ozone that annually occurs over Antarctica during the Austral spring (August-November). Chlorine and bromine from human-produced compounds cause the ozone hole. The Montreal Protocol regulated these ozone depleting substances (ODSs), but these compounds have very long atmospheric lifetimes. Hence, the ozone hole will slowly recover through the 21st century. In this presentation we will discuss the various factors that influence the severity of the Antarctic ozone depletion, including ODS, meteorological conditions, and climate forcings. In particular, we will review the evidence that the ozone hole is currently mending, and will show an ensemble of GSFC GEOSCCM model projections on the recovery. Currently, models project a recovery back to 1980 levels in about 2070. However, changing meteorological conditions, and varying future greenhouse gas projections modify these recovery estimates.