If you read the report carefully below, you will see that the hole has been EXPANDING in recent years, not shrinking and that it is "still large" compared to the 1980s. So their optimism about it shrinking is just speculative modelling. It is 35 years since the agreement designed to close the hole was made but on the actual measurements the hole is clearly going nowhere
Earth's ozone layer is healing at a pace that would see the layer between the polar regions reach pre-1980 levels by 2040, the United Nations revealed Monday.
Scientists said that global emissions of chlorofluorocarbon-11 (CFC-11), a banned chemical used as a refrigerant and insulating foams, had declined since 2018 after increasing for several years.
The assessment found that the 8.91-million-square-mile hole over Antarctica will close by 2066 and the atmospheric layer above the Arctic will return to normal by 2045.
The announcement comes more than 35 years after every nation in the world agreed to stop producing chemicals that chop on the layer of ozone in Earth's atmosphere that shields the planet from harmful radiation linked to skin cancer, cataracts and crop damage.
The ozone layer is a natural layer of gas located in the stratosphere – the second layer in Earth's atmosphere.
Although warmer-than-average stratospheric weather conditions have reduced ozone depletion during the past two years, the current ozone hole area is still large compared to the 1980s - when the depletion of the ozone layer above Antarctica was first detected.
In the 1970s, it was recognized that CFCs were destroying ozone in the stratosphere. In 1987, the Montreal Protocol was agreed upon, which led to the phase-out of CFCs and, recently, the first signs of recovery of the Antarctic ozone layer.
According to the report, the first signs of ozone healing were observed four years ago.
Chlorine levels are down 11.5 percent since they peaked in 1993, and bromine, which is more efficient at eating ozone but is at lower levels in the air, dropped 14.5 percent since its 1999 peak, the report said.
That bromine and chlorine levels 'stopped growing and is coming down is a real testament to the effectiveness of the Montreal Protocol,' Paul Newman, co-chair of the scientific assessment, said.
Natural weather patterns in the Antarctic also affect ozone hole levels, which peak in the fall.
And the holes have been a bit bigger the past couple of years because of that, but the overall trend is one of healing, Newman said.
The recovery is 'saving 2 million people every year from skin cancer,' United Nations Environment Program Director Inger Andersen told The Associated Press earlier this year in an email.
The Ozone layer sits in the stratosphere 25 miles above the Earth's surface and acts like a natural sunscreen
Ozone is a molecule comprised of three oxygen atoms that occurs naturally in small amounts.
In the stratosphere, roughly seven to 25 miles above Earth's surface, the ozone layer acts like sunscreen, shielding the planet from potentially harmful ultraviolet radiation that can cause skin cancer and cataracts, suppress immune systems and also damage plants.
It is produced in tropical latitudes and distributed around the globe.
Although warmer-than-average stratospheric weather conditions have reduced ozone depletion during the past two years, the current ozone hole area is still large compared to the 1980s, when the depletion of the ozone layer above Antarctica was first detected.
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