Overview
- Government scientists reported on Wednesday that the 2026 Antarctic ozone hole reached a one-day peak of 10.5 million square miles and ranked seventh largest in 48 years of observations.
- During the main depletion season from Sept. 7 to Oct. 13 the hole averaged about 9.6 million square miles, a size driven mainly by an unusually large and persistent polar vortex.
- Researchers using NOAA balloon sondes and multiple satellites found the lowest overhead ozone this year was 105 Dobson units on Oct. 17, showing the hole was wide in area but not as deep as some past extremes.
- NOAA and NASA scientists attribute the 2026 size to meteorology—weak planetary-scale wave activity that failed to break up the vortex—not to a new surge in ozone-depleting emissions.
- Long-term recovery remains on track because stratospheric chlorine from old chemicals has fallen about one-third since the 1980s, and scientists expect the Antarctic ozone hole to heal by the 2070s as those legacy compounds decline.