Updated · National Oceanic and Atmospheric Administration · Nov 4
Antarctic Ozone Hole Ranks 7th-Largest at 9.6 Million Square Miles as Polar Vortex Swells
Updated
Updated · National Oceanic and Atmospheric Administration · Nov 4
Antarctic Ozone Hole Ranks 7th-Largest at 9.6 Million Square Miles as Polar Vortex Swells
3 articles · Updated · National Oceanic and Atmospheric Administration · Nov 4
Summary
NOAA and NASA said the 2026 Antarctic ozone hole averaged 9.6 million square miles from Sept. 7 to Oct. 13, making it the seventh-largest in 48 years of records.
A powerful polar vortex drove the expansion by trapping unusually cold air over a wider area after weak August-September wave activity failed to disrupt the vortex.
The hole peaked at 10.5 million square miles on Sept. 18—about 90% of the 2000 record—while ozone over the South Pole fell to 105 Dobson units on Oct. 17, above the record low of 92 in 2006.
Scientists said the hole would have been 1 million to 2 million square miles larger without cuts in ozone-depleting chemicals under the 1987 Montreal Protocol.
Long-term recovery remains on track, with Antarctic stratospheric chlorine down about one-third from its peak and the ozone hole still expected to recover by the 2070s.