According to a 2022 assessment by a United Nations-backed panel of scientists, the ozone layer should fully recover within four decades. Due to international efforts to phase out ozone-damaging chemicals, the delicate part of the stratosphere has slowly started thickening. (The stratosphere is a layer of the Earth’s atmosphere). Experts stated that if current policies remain in effect, most of the world’s ozone layer should recover to 1980 levels by 2040.
However, the world’s polar regions will take a bit longer to see improvements. The ozone should recuperate by 2045 over the Arctic and by around 2066 across Antarctic regions.
The UN-backed panel of experts presented their findings at the American Meteorological Society’s annual meeting in January 2023. During the assembly, they applauded global policies to gradually eliminate 99% of banned ozone-depleting substances (ODS).
Scientists first discovered the harmful impact that refrigerants, aerosols, and solvents had on the environment in the 1980s. These products contain chlorofluorocarbons, or CFCs, that contribute to ozone layer damage. When experts first noticed the hole in the ozone, they sounded the alarm about these chemicals.
Due to their findings, nations around the globe united in adopting the Montreal Protocol in 1987. It’s the first international treaty in the history of the UN to achieve universal ratification. Considered by many as the most successful environmental action to date, the landmark agreement banned nearly 100 artificial chemicals.
Allowing them to remain in production would cause further ozone damage, exposing Earth to more of the sun’s harmful ultraviolet (UV) rays. Nearly 40 years later, scientists have observed significant improvements in the ozone layer in the upper stratosphere. Furthermore, since 2000, the Antarctic ozone hole has begun to shrink and thicken, both signs of the Montreal Protocol’s success.
Scientists Explain How Controlling Pollution Positively Impacts the Planet and Atmosphere
According to the UN Environment Program (UNEP), ozone deterioration would have accelerated tenfold by 2050 without the Montreal Protocol. Due to increased UV radiation, this would’ve resulted in millions of additional cases of melanoma, other cancers, and cataracts. Experts estimate that the international treaty saves about two million people annually from skin cancer.
Plus, phasing out these chemicals aids in climate mitigation since many ODS artificially warm the planet. From 1990 to 2010, the treaty’s policies reduced greenhouse gas emissions from banned substances by eleven gigatons a year.
“That ozone recovery is on track according to the latest quadrennial report is fantastic news. The impact the Montreal Protocol has had on climate change mitigation cannot be overstressed. Over the last 35 years, the Protocol has become a true champion for the environment,” said Meg Seki, Executive Secretary of the United Nations Environment Programme’s Ozone Secretariat, in a press release.
“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,” she continued.
Amendments to Montreal Protocol Protect Ozone Layer
The recent report by the Scientific Assessment Panel confirms the treaty’s unprecedented positive environmental impact. In 2007, the UN adopted the Montreal Amendment to address hydrochlorofluorocarbons (HCFCs), potent gases used globally in air conditioning and refrigeration. Since they deplete the ozone layer and contribute to global warming, the Parties to the Protocol decided to accelerate the phaseout schedule of HCFCs.
Developed countries stopped using them in 2020, and developing countries agreed to eliminate them by 2030. Scientists estimate that the aggressive phase-out of HCFCs will avoid up to 0.5°C of warming by 2100 and over 80 billion metric tons of CO2 equivalent emissions by 2050.
An additional 2016 agreement, known as the Kigali Amendment to the Montreal Protocol, requires phasing out a group of substances called hydrofluorocarbons (HFCs). While HFCs don’t deplete the stratospheric ozone, they are potent greenhouse gases estimated to account for 7-19% of global CO2 emissions by 2050. The Scientific Assessment Panel said this amendment will prevent 0.3-0.5°C of warming by 2100 (this does not include climate impacts from HFC-23 emissions).
“Ozone action sets a precedent for climate action. 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,” said WMO Secretary-General Prof. Petteri Taalas.
Scientists Address Risks of Geoengineering to Control Climate Change
For the first time in their assessment published every four years, the expert panel investigated the possibilities of geoengineering. Many scientists have proposed injecting sulfur aerosols into the stratosphere layer of the atmosphere to deflect some of the sun’s intense rays.
Also known as stratospheric aerosol injection (SAI), spraying aerosols into the stratosphere would reduce global warming, according to experts. However, the panel warned that the unproven technology “could also affect stratospheric temperatures, circulation and ozone production and destruction rates and transport.”
In addition, other studies have found that stratospheric aerosol injection techniques could cause extreme weather, droughts, and lower crop yields. Not to mention, it would require global coordination to ensure successful deployment. Other experts have cited concerns over costs, technological limitations, and the potential impacts on human and animal life. However, more research is necessary to determine the safety and feasibility of solar geoengineering.
The panel of experts involved in the latest UN-backed assessment included the World Meteorological Organization (WMO), United Nations Environment Program (UNEP), the US National Oceanic and Atmospheric Administration (NOAA), the US National Aeronautics and Space Administration (NASA) and European Union.
Final Thoughts on the Ozone Layer Making a Recovery of the Atmosphere
Since the late 1970s and 1980s, scientists have warned about the unintended consequences of ozone-depleting substances (ODS) to the atmosphere. They said that if we didn’t phase them out, harmful levels of UV radiation would reach Earth’s surface due to the deteriorating ozone layer. Fortunately, the world united to sign the Montreal Protocol, a landmark agreement to ban chemicals that damage the ozonosphere.
Scientists estimate that the ozone layer will fully recover to 1980 levels by 2040 for much of the world. Polar regions may take a couple of decades to see pollution prevention strategies’ positive impacts.