Most observations of ozone holes are concentrated over Antarctica, but now scientists have discovered the largest hole in the ozone layer over the past 25 years over the Arctic.
According to the researchers, the ozone layer protects the Earth from the worst ultraviolet radiation from the Sun, but was discovered in this layer in Antarctica in the late 1980s. It was found that the main culprit of its formation are chlorofluorocarbons (CFCs) – chemicals that were widely used at that time in aerosols and refrigerants. In response to the problem, the Montreal Protocol demanded that countries around the world abandon CFCs, and the hole has been steadily shrinking for decades since then.
The Arctic goes through a similar cycle with ozone levels that fluctuate throughout the year. But since the temperature there is not as low as in Antarctica, such large gaps have never been observed in the ozone layer around the North Pole. Anyway, still.
So, an unusually strong drop in ozone levels over the Arctic was discovered by scientists from the German Aerospace Center. Since March 14, ozone levels have fallen by less than 220 Dobson units, which can be considered a full-fledged ozone hole.