An ozone hole that formed over the Arctic this spring and eventually grew into the largest ever recorded has closed.
It’s recovery cannot be entirely linked to the reduction in pollution due to the coronavirus pandemic.
Scientists who were tracking the hole at Copernicus’ Atmospheric Monitoring Service (CAMS) announced last week that the “rather unusual” hole was caused not by human activity but a particularly strong Arctic polar vortex.
“COVID19 and the associated lockdowns probably had nothing to do with this,” the group said on Twitter.
“It’s been driven by an unusually strong and long-lived polar vortex, and isn’t related to air quality changes.”
Due to the hole, most of the ozone typically found around 11 miles into the stratosphere was depleted. The last time such a strong chemical ozone depletion was observed in the Arctic occurred nearly a decade ago.
The ozone layer sits between 9 and 22 miles above the Earth. It protects us from ultraviolet radiation.
A polar vortex is a large area of low pressure and cold air that surrounds both of Earth’s poles, according to the National Weather Service. Polar vortexes typically weaken during the summer and strengthen in the winter.