Record ozone hole over Arctic now gone
A record-breaking ozone hole that formed over the Arctic this spring has closed, researchers announced late last week.
Scientists at the Copernicus’ Atmospheric Monitoring Service tracking the “rather unusual” ozone hole announced Thursday on Twitter that it had ended. The group said the hole was caused by a polar vortex and closed when that vortex split.
“COVID-19 and the associated lockdowns probably had nothing to do with this,” the group said repeatedly on Twitter. “It’s been driven by an unusually strong and long-lived polar vortex, and isn’t related to air quality changes.”
A polar vortex is a large area of cold air high in the atmosphere that normally spins over the North Pole. An ozone hole is a dramatic thinning of the ozone layer that’s typically boosted in size by colder temperatures.
Ozone holes have formed annually for the past 35 years in the Antarctic because of human-made chemicals migrating into the stratosphere and accumulating inside a strong polar vortex, the group said. Because of unusually high temperatures high above Antarctica, the ozone hole shrank to its smallest size on record last October.
In the Arctic however, polar vortexes are much weaker, meaning the conditions needed for such strong ozone depletion aren’t normally found, making this ozone hole “unprecedented.”
Ozone depletion over the Arctic in 2020 was so severe that most of the ozone at an altitude of around 11 miles had been depleted. Researchers said the last time a similarly strong chemical ozone depletion was observed over the Arctic was in spring 2011.
The ozone layer is important because it acts like a sunscreen, blocking potentially harmful ultraviolet energy from reaching our planet’s surface.