The ozone layer that protects the Earth is slowly but surely recovering, and at this rate the ozone hole over Antarctica will disappear in about 43 years, according to the MTI report based on a UN report.
A quarterly scientific survey commissioned by the United Nations has revealed an improvement 35 years after the world’s nations pledged to halt production of chemicals that weaken the Earth’s ozone layer. The ozone layer protects against harmful radiation that causes skin cancer, cataracts and damages crops.
“We found an improvement in the upper stratosphere and the ozone hole”
– said Paul Newman, co-chair of the Science Survey Board.
And according to a report presented to the American Meteorological Society in Denver on Monday, the process is slow. The ozone layer in the upper atmosphere, which is 30 km thick on average, is expected to return to pre-1980 levels by 2040, over the Arctic by 2045, and over Antarctica by 2066, according to the report.
Naturalists and environmentalists around the world have made longstanding efforts to remedy the ozone hole, until in 1987 the Montreal Protocol banned halogenated hydrocarbon derivatives (CFCs) containing chlorine and/or fluorine, chemicals used in refrigerators and as aerosol propellants.
“Steps taken to protect the ozone layer set a precedent for climate protection. Our success in phasing out ozone-depleting chemicals is evidence that we can — and urgently must — replace fossil fuels, reduce the greenhouse effect, and thus reduce global warming.”
– Petteri Taalas, Secretary General of the World Meteorological Organization, wrote in his statement.
According to Newman, the improvement was already evident four years ago, but it was much less, and since then the trend has strengthened.
Two compounds that play a major role in destroying the ozone layer are present in lower levels in the atmosphere, said Newman, chief earth scientist at NASA’s Goddard Space Flight Center. The level of chlorine fell 11.5 percent after a peak in 1993, and the level of bromine, which damages the ozone layer the most but is found in smaller amounts in the air, has fallen 14.5 percent compared to the 1999 record. The increase in bromine and chlorine levels has stalled and receded, Newman said. It is real evidence of the effectiveness of the Montreal Protocol.
Natural weather phenomena in Antarctica also affect the level of the ozone hole, which peaks in the fall. That’s why ozone holes have gotten a little bigger in the past couple of years, but according to Newman, the general trend is recovery. According to Inger Andersen, director of the United Nations Environmental Protection Programme, healing the ozone hole would save two million people from cancer every year.