This hole that was created in the ozone layer of Earth’s atmosphere will be the third longest-lasting one in over four decades. The Earth’s ozone layer lies within the lower lever of the stratosphere at approximately 15 to 35 kilometres above Earth.
This thin layer protects life on earth by absorbing most of the Sun’s harmful ultraviolet radiation.
In 1976, scientists discovered that this protective layer was being damaged by chemicals released by industry, mainly chlorofluorocarbons (CFCs).
Atmospheric research revealed that this depletion was much higher than could be accounted for by natural causes like temperature, weather and volcanic eruptions.
Every year a large hole opens up in the ozone layer during the southern hemisphere’s summer.
Meanwhile, the size of the annual hole depends on a range of weather conditions and is augmented by cold.
However, experts predict that these holes will close for good by 2050, as a result of a global restriction on ozone-depleting chemicals introduced in the late 80s.
In 1987, countries around the world signed the Montreal Protocol that capped the production of CFCs at 1986 levels with commitments to long-term reductions.
“These two longer-than-usual episodes in a row are not a sign that the Montreal Protocol is not working though, as without it, they would have been even larger.
“It is because of interannual variability due to meteorological and dynamical conditions that can have an important impact on the magnitude of the ozone hole and are superimposed on the long-term recovery.
CAMS also tracks the amount of UV radiation that reaches the Earth’s surface and recently they have observed very high UV indexes, in excess of 8, over parts of Antarctica situated below the ozone hole.
The UV index forecast identifies the strength of the ultraviolet radiation coming from the sun at a particular point.
The index ranges on a scale of 1-11, with 8 being labelled “very high”.