Why is it happening? The ozone hole over Antarctica is a problem. It is closing a month later than usual for the third year in a row. The Copernicus Earth Observation Program report details the ozone layer anomaly.
It declined the most since the early 2000s. But scientists can’t explain why it now persists so long. It usually opens in September before contracting in November, coinciding with spring in the southern hemisphere. In 2022, the hole is expected to close in the next few days.
Caring for the ozone
What was it like in 2021? The ozone hole lasted until December 23. The 2020 hole lasted until December 28, the longest duration on record. The 2019 hole was the smallest and shortest duration since observations began in 1979.
Ozone depletion has been observed since the late 1970s. The Montreal Protocol then established a ban on ozone-depleting chemicals. It entered into force in 1989. It has the merit of having slowed this decline. The surface of the Antarctic hole peaked in 2000. Since then, it has been slowly shrinking.
The origin of the ozone anomaly is not known with certainty. But the researchers put forward some suggestions. First, they cited global warming. According to them, it paradoxically causes cooling of the middle and upper stratosphere. This prolongs the duration of the hole.
Volcanoes
Second, they suggested that the eruption of the Hunga Tonga volcano in January was related. It may have altered the normal stratospheric aerosol balance. However, that remains a matter of research.
The ozone layer filters out 97% to 99% of the Sun’s ultraviolet (UV) radiation. This allows life to flourish on Earth. Exposure to UV radiation increases the risk of skin cancer, eye damage and premature aging.
