The perpetual worry about the growing hole in the ozone layer seems to have vanished from the collective consciousness. It seemed like everyone was talking about it for a while and suddenly stopped. What happened to that ominous hole in the ozone layer and why should its absence from conversation give us hope?
The Ozone Hole
Ozone is one of the gasses making up the Earth’s atmosphere, though it is primarily concentrated in the stratosphere. The ozone layer is a protective film of this gas that absorbs UVB ultraviolet radiation from sunlight, reducing the amount that makes it to the surface.
In 1985, scientists discovered a massive hole in the ozone layer above Antarctica. This ozone depletion became colloquially known as a hole in the ozone layer and it was front-page news for many years during the late 1980s and early 1990s.
Researchers discovered artificial chemicals in the atmosphere were causing ozone depletion. Chlorofluorocarbons — or CFCs — were used as propellants in everything from asthma inhalers to hairspray, air conditioners and appliance refrigerants. Roughly 84% of the chemicals causing ozone depletion were found to be artificial, which meant there needed to be a change.
Responses and Reactions
In 1987 — two years after the discovery of the Antarctic ozone hole — the United Nations introduced the Montreal Protocol on Substances that Deplete the Ozone Layer. Its goal was to reduce the number of artificial chemicals like CFCs released into the atmosphere to counter the damaging effects. The Montreal Protocol included control measures, control levels and a list of substances controlled or outlawed by the treaty.
When it was ratified on September 16, 1987, it became the first UN treaty ratified in all 198 countries worldwide. More than 35 years later, its effects were monumental. By 2019, the hole in the ozone layer was the smallest since scientists started monitoring it in 1982, but the work isn’t done.
The Kigali and Montreal Amendments
When the Montreal Protocol banned the use of CFCs, companies relying on these chemicals needed an alternative. Hydrofluorocarbons (HFCs) became the replacement for freon and refrigerants for air conditioners and refrigerators. HFCs were marketed as non-ozone depleting, but research shows they have a high global warming potential (GWP).
Despite the threat, HFC emissions are growing by about 8% annually and could rise as high as 19% annually by 2050. In response, the UN ratified the Kigali Amendment in 2019, which includes a timeline to reduce the use of HFCs by 80-85% between 2019 and 2040.
HFCs aren’t the only material on the chopping block for a high GWP. Hydrochlorofluorocarbons (HCFCs) were also marketed as a non-ozone-depleting alternative for air conditioner refrigerant R22. Unfortunately, research shows HCFCs are up to 2,000 times more potent than carbon dioxide in their GWP. Countries have been working to reduce their reliance on HCFCs for years. In 2020, the United States ceased production of R22 refrigerant entirely, though reclaimed or recycled supplies are still available.
Hope For the Future
The topic of climate change is on everyone’s mind as countries worldwide struggle to reduce their CO2 output. The global goal is to reduce CO2 production by 40% before 2030 and reach net zero emissions by 2050. It might seem impossible, but all people have to do is look backward to prove everyone has what it takes to achieve this goal.
In 2022, scientists announced the ozone layer had reached a remarkable milestone. It’s at just over 50% of the levels they observed before 1980 — meaning the global changes are working. There’s still a long way to go before professionals can say the ozone layer is fully healed, but if trends continue, they could see levels comparable to pre-1980 measurements by 2070.
The healing of the ozone layer isn’t just good for the planet — it also gives hope for the future. Everyone can come together as a species and make changes to improve the environment and leave the world a better place for future generations.