The ozone hole over Antarctica is one of the widest and deepest
Sylvie Claire / September 6, 2020
The ozone hole over Antarctica has reached its maximum size this year, according to scientists from the Copernicus Service for Atmospheric Monitoring (CAMS). They say it is one of the widest and deepest seen in the past 15 years. "This confirms that we must continue to apply the Montreal Protocol banning the emissions of chemicals that deplete the ozone layer," said Vincent-Henri Peuch, director of CAMS at the European Center for Medium-Range Weather Forecasts.
Stratospheric ozone concentrations have been reduced to near zero values over Antarctica at an altitude of about 20 to 25 km. The depth of the ozone layer is just below 100 Dobson units, or about a third of its typical value outside of ozone hole events. This phenomenon is due to a strong, stable and cold polar vortex.
“There is a great deal of variability in how events related to the ozone hole develop each year,” says Peuch. “The ozone hole in 2020 looks like the one in 2018, which was also quite a big hole. With sunlight returning to the South Pole in recent weeks, we have seen continued depletion of the ozone layer over the region. «
The Montreal Protocol, signed in 1987, aims to protect the ozone layer, which acts as a filter for UV radiation from the sun. To this end, it obliges the participating countries to phase out harmful substances which deplete it. These include chlorofluorocarbons (CFCs), found in refrigerators and aerosols.
Credit : Sudinfo