The Earth's ozone layer is on its way to recovering, thanks to decades of work to get rid of ozone-damaging chemicals, a panel of international experts backed by the United Nations has found.
The ozone layer serves an important function for living things on Earth. This shield in the stratosphere protects humans and the environment from harmful levels of the sun's ultraviolet radiation.
The international community was alarmed after experts discovered a hole in the ozone layer in May 1985. Scientists had previously discovered that chemicals such as chlorofluorocarbons, used in manufacturing aerosol sprays and used as solvents and refrigerants, could destroy ozone.
Two years after the discovery of the dire state of the ozone layer, international bodies adopted a global agreement called the Montreal Protocol. This established the phaseout of almost 100 synthetic chemicals that were tied to the destruction of the all-important ozone.
In the latest report on the progress of the Montreal Protocol, the U.N.-backed panel confirmed that nearly 99% of banned ozone-depleting substances have been phased out.
If current policies stay in place, the ozone layer is expected to recover to 1980 values by 2040, the U.N. announced.
In some places, it may take longer. Experts said that 1980-level recovery over Antarctica is expected by around 2066 and by 2045 over the Arctic.
"The impact the Montreal Protocol has had on climate change mitigation cannot be overstressed," said Meg Seki, executive secretary of the U.N. Environment Programme's Ozone Secretariat, in a statement. "Over the last 35 years, the Protocol has become a true champion for the environment. The assessments and reviews undertaken by the Scientific Assessment Panel remain a vital component of the work of the Protocol that helps inform policy and decision-makers."
The depletion of the ozone layer is not a major cause of climate change. But research is showing that these efforts to save the ozone layer are proving beneficial in the fight against climate change.
In 2016, an amendment to the Montreal Protocol required the phaseout of the production and consumption of some hydrofluorocarbons. These HFCs don't directly deplete the ozone layer, but they are powerful greenhouse gases — which contribute to accelerated climate change and global warming, the U.N. says.
The Kigali Amendment will "avoid 0.3–0.5 °C of warming by 2100," the report estimates.
"Ozone action sets a precedent for climate action," said World Meteorological Organization Secretary-General Petteri Taalas. "Our success in phasing out ozone-eating chemicals shows us what can and must be done – as a matter of urgency – to transition away from fossil fuels, reduce greenhouse gases and so limit temperature increase."
