Findings of Report:-
The Earth’s protective ozone layer is on track to recover within four decades, closing an ozone hole that was first noticed in the 1980s, a United Nations-backed panel of experts announced on Monday. The findings of the scientific assessment, which is published every four years,more than 35 years after every nation in the world agreed to stop producing chemicals that chomp on the layer of ozone in Earth’s atmosphere that shields the planet from harmful radiation ,follow the landmark Montreal Protocol in 1987, which banned the production and consumption of chemicals that eat away at the planet’s ozone layer.
- Scientists said the recovery is gradual and will take many years. If current policies remain in place, the ozone layer is expected to recover to 1980 levels — before the appearance of the ozone hole — by 2040, the report said, and will return to normal in the Arctic by 2045. Additionally, Antarctica could experience normal levels by 2066.
- Scientists and environmental groups have long lauded the global ban of ozone-depleting chemicals as one of the most critical environmental achievements to date, and it could set a precedent for broader regulation of climate-warming emissions.
- Scientists said that global emissions of the banned chemical chlorofluorocarbon-11, or CFC-11, which was used as a refrigerant and in insulating foams, have declined since 2018 after increasing unexpectedly for several years. A large portion of the unexpected CFC-11 emissions originated from eastern China, the report said.
- The report also found that the ozone-depleting chemical chlorine declined 11.5% in the stratosphere since it peaked in 1993, while bromine declined 14.5% since it peaked in 1999.
- Scientists also warned that efforts to artificially cool the Earth by injecting aerosols into the upper atmosphere to reflect sunlight could thin the ozone layer, and cautioned that further research into emerging technologies like geoengineering is necessary.
Researchers with the World Meteorological Organization, the United Nations Environment Program, the National Oceanic and Atmospheric Administration, the National Aeronautics and Space Administration and the European Commission contributed to the assessment.
The ozone layer or ozone shield is a region of Earth’s stratosphere that absorbs most of the Sun’s ultraviolet radiation. It contains a high concentration of ozone (O3) in relation to other parts of the atmosphere, although still small in relation to other gases in the stratosphere. The ozone layer contains less than 10 parts per million of ozone, while the average ozone concentration in Earth’s atmosphere as a whole is about 0.3 parts per million. The ozone layer is mainly found in the lower portion of the stratosphere, from approximately 15 to 35 kilometers (9 to 22 mi) above Earth, although its thickness varies seasonally and geographically. The ozone layer in the upper atmosphere protects the Earth from the sun’s ultraviolet radiation, which is linked to skin cancer, eye cataracts, compromised immune systems and agricultural land damage.
About Montreal Protocol:-
The Montreal Protocol on Substances that Deplete the Ozone Layer is the landmark multilateral environmental agreement that regulates the production and consumption of nearly 100 man-made chemicals referred to as ozone depleting substances (ODS). When released to the atmosphere, those chemicals damage the stratospheric ozone layer, Earth’s protective shield that protects humans and the environment from harmful levels of ultraviolet radiation from the sun. Adopted on 16 September 1987, the Protocol is to date one of the rare treaties to achieve universal ratification.