Summary
The 2015 ozone hole only started developing during the third week of August, which is the latest onset of the ozone hole that has been seen since the mid-to-late 1980s. However, record cold stratospheric temperatures and a very stable polar vortex have since seen the 2015 ozone hole become one of the biggest on record, at least in terms of its areal extent (3rd to 4th largest on record). Also, during October the ozone hole set new maximum area records for this time of year.The development and recovery of the 2015 ozone hole will be shown via a set of metrics based on the Ozone Monitoring Instrument (OMI) on board the Earth Observing Satellite (EOS) Aura, and the OMPS (Ozone Mapping and Profiler Suite) instrument on the Suomi National Polar-orbiting Partnership satellite (Suomi NPP). Other observational results will be shown to complement these satellite data. The 2015 ozone hole metrics will be compared to the historical metrics, and these will be linearly regressed against Equivalent Effective Stratospheric Chlorine (EESC) data that are based entirely on Cape Grim Air Archive, Antarctic firn and AGAGE global measurements of ozone depleting substances (ODS). The year-to-year variability of the ozone hole does not reflect variations in the level of ODSs in the Antarctic stratosphere, which, based on surface observations, have fallen approximately 10% since their peak around 2000, or have fallen by approximately 18% since their peak around 2000 relative to 1980 levels of ODSs. The decadal variations in the ozone hole do reflect the long-term changes of ODSs in the Antarctic stratosphere and the results shown here suggest that ozone hole recovery has commenced, despite the 2015 ozone hole being relatively large.
Related projects
