The hole had formed earlier this year and reached its maximum size only a few weeks ago in mid-March. It was the largest ozone hole ever recorded and now it appears to have vanished.
Researchers believe the hole was caused by an unusually strong polar vortex and have said its disappearance probably has nothing to do with the drop in air pollution due to the coronavirus lockdown.
The polar vortex is a high-altitude current that circulates in an irregular ring-like pattern around the Arctic and helps keep cold air trapped above the pole.
‘It is very unusual for such strong ozone depletion to occur in the northern hemisphere, but this year’s polar vortex was exceptionally strong and persistent, and temperatures were low enough to allow stratospheric cloud formation for several months,’ Antje Inness from the Copernicus’ Atmospheric Monitoring Service told Euro News.
Ozone helps filter ultraviolet light from the atmosphere, and when holes appear it means more harmful solar radiation is penetrating the atmosphere and reaching the Earth’s surface.
A massive hole has opened up in the ozone layer which had opened up above the Artic, because of climate change and the atypically cooler temperatures in the atmosphere above the north pole, for this time of the year, have led to this rapid depletion of the ozone in that region.
“In 2020 the Arctic polar vortex has been exceptionally strong and long lived. Furthermore, temperatures in the Arctic stratosphere were low enough for several months at the start of 2020 to allow the formation of PSCs, resulting in large ozone losses over the Arctic,” said CAMS.