The ozone hole over Antarctica has grown to one of the largest sizes in history this year, covering an area nearly three times the size of Brazil. Scientists at the Copernicus Atmosphere Monitoring Service believe the extraordinarily large ozone depletion may have something to do with last year’s massive volcanic eruption that spewed large amounts of water into Earth’s atmosphere.
New measurements taken from the Copernicus Sentinel-5P satellite show that Antarctica’s ozone hole, known as the “ozone losing zone”, reached a near-record size, reaching 26 million square kilometers on September 16 this year.
“Our operational ozone monitoring and forecasting service shows that the 2023 ozone hole started early and has been growing rapidly since mid-August,” Antje Inness, senior scientist at the Copernicus Atmosphere Monitoring Service, said in a statement. “On September 16, it reached a size of over 26 million square kilometers, making it one of the largest ozone holes on record,” he said.
Antarctica’s ozone hole has an ever-changing structure and grows and shrinks depending on the seasons. The size of the ozone hole increases from August to October, when the Southern Hemisphere enters spring and temperatures begin to rise. It continues to grow until mid-October, when temperatures weaken the polar vortex and it eventually becomes hot enough to break apart.
It’s not bad news; just a pause
As a broader trend, the hole in the ozone layer is actually shrinking in size and appears to be on track to fully recover within a few decades. This improvement is largely thanks to the gradual elimination of chlorofluorocarbons (CFCs), man-made chemicals once widely used in aerosol sprays, solvents and refrigerants that deplete the ozone layer as they slowly rise into the stratosphere.
So this record size does not seem to be a major concern for now. The hole, which has grown to surprisingly large sizes this spring, will likely be a pause that bucks a larger trend. ESA believes it is too early to make predictions about the reasons behind the current state of the ozone hole, but some suggest that this year’s unusual ozone movements may have a link to the Hunga Tonga-Hunga Ha’apai eruption in January 2022.
This underwater explosion released energy equivalent to 20 megatons of TNT in a series of five explosions, making it the largest natural explosion ever recorded. The explosion caused significant amounts of water vapor to rise into the Earth’s atmosphere, which may be affecting ozone concentrations in the stratosphere.
“The eruption of the Hunga Tonga volcano in January 2022 injected a lot of water vapor into the stratosphere, and this water vapor only reached the southern polar regions after the end of the 2022 ozone hole,” says Inness. “The water vapor was formed by chlorofluorocarbons (CFCs).” It may have led to increased formation of polar stratospheric clouds, where it could react and accelerate ozone depletion. “The presence of water vapor may also contribute to the cooling of the Antarctic stratosphere, which could further increase the formation of polar stratospheric clouds, leading to a more robust polar vortex.”