The ozone hole over Antarctica, which reached enormous proportions in autumn 2020, closed at the end of December, said Claire Nullis, spokesman for the World Meteorological Organization (WMO).
Nullis explained that this ozone hole was one of the largest and deepest, and also closed later than usual. It grew rapidly from mid-August 2020 and reached a peak size of 24.8 million square kilometers in September. The size and depth of the ozone hole are attributed to “a strong, stable and cold polar vortex and very low temperatures in the stratosphere.”
In April 2020, the huge ozone hole over the Arctic, which formed in March, tightened on its own. The hole, nearly a million square kilometers from Hudson Bay in Canada to the Arctic islands in Russia, was caused by a strong polar vortex, not by man.