The ozone layer, a thin part of the Earth’s atmosphere that absorbs most of the ultraviolet radiation from the Sun, may recover in just a few decades, according to a major assessment by the United Nations, US, and European Union agencies. An international agreement was reached in 1987 to phase out harmful chemicals, such as chlorofluorocarbons (CFCs), which were commonly found in spray cans, fridges, foam insulation, and air conditioners, that were eating away at the ozone layer. Almost 99% of banned ozone-depleting substances have now been phased out, and the report co-produced by UN, US, and EU agencies says the Montreal Protocol is working as hoped. If current policies are maintained, the ozone layer will be restored to 1980 values before the ozone hole appeared by different points in different places: 2066 over the Antarctic, where ozone depletion was the worst, 2045 over the Arctic, and in about two decades everywhere else.
The ozone layer began depleting in the 1970s, and a gaping hole in the layer was discovered by scientists in 1985. The depletion of the ozone layer is harmful due to solar radiation, and ultraviolet rays can damage DNA and cause sunburn, increasing the long-term risk of problems such as skin cancer. The Antarctic ozone hole continued expanding until 2000, after which its area and depth began improving slowly.
The Montreal Protocol became the first UN treaty to achieve universal ratification, and saving the ozone layer has had a positive knock-on effect on global warming. That phase-out will have prevented up to 1C of warming by the middle of the century, compared to increasing their use by 3% per year. International action to avert environmental crises can work, but continued progress on the ozone layer is not guaranteed.
While the progress made on the ozone layer is a positive step, there is still more work to be done in the fight against climate change. Experts urge countries to take swift action to reduce carbon emissions and invest in renewable energy sources to limit global warming and its damaging effects. The report demonstrates that international cooperation and commitments can make a significant difference in protecting the environment, and continued efforts are necessary to ensure the recovery of the ozone layer and a sustainable future for the planet.
