https://www.nasa.gov/feature/goddard/2019/2019-ozone-...

Uncommon but not unprecedented

This is the third time in the last 40 years that weather systems have caused warm temperatures that limit ozone depletion, said Susan Strahan, an atmospheric scientist with Universities Space Research Association, who works at NASA Goddard. Similar weather patterns in the Antarctic stratosphere in September 1988 and 2002 also produced atypically small ozone holes, she said.

https://www.cnet.com/news/2020-antarctic-ozone-hole-o...

The size of the hole fluctuates and reaches its maximum size sometime in September or October every year. The Copernicus Sentinel-5P satellite is tasked with watching the ozone hole. The German Aerospace Center crunched the data and determined the hole has hits its peak for 2020 and ozone levels are set to recover by the end of the year.

The 2020 hole reached a size of about 9.6 million square miles (25 million square kilometers) in early October. ESA said this size was comparable with the holes that formed in 2015 and 2018.