There was a time, not so long ago, when humanity looked up at the sky and realized it was disappearing. Not the blue of it, and not the clouds — but something invisible and irreplaceable: the ozone layer, the thin atmospheric shield that had protected life on Earth for four billion years from the sun's most damaging ultraviolet radiation.

In the 1970s, chemists Frank Sherwood Rowland and Mario Molina at the University of California, Irvine made a disturbing discovery. The chlorofluorocarbons, or CFCs, used in refrigerators, air conditioners, and aerosol spray cans were rising into the stratosphere and catalytically destroying ozone molecules. Each CFC molecule could destroy tens of thousands of ozone molecules. In 1985, British Antarctic Survey scientists confirmed the nightmare: a massive hole had opened in the ozone layer above Antarctica. Without intervention, scientists projected that ODS levels in the atmosphere could increase tenfold by 2050, with catastrophic consequences for human health, agriculture, and marine ecosystems.

Nations had every reason to delay. The chemicals at risk were economically important. Alternatives were expensive and unproven. Powerful industries had financial incentives to cast doubt on the science. And yet, on September 16, 1987, in Montreal, Canada, the world chose to act. Representatives from 24 nations signed the Montreal Protocol on Substances That Deplete the Ozone Layer — a binding commitment to phase out the production and consumption of ozone-depleting substances.

This was an AMAZING moment because it proved something that had never been proven before: that the nations of the world could agree, in real time, to reverse a planetary-scale environmental crisis before it became irreversible.

The numbers that followed are staggering. By 2010, the Montreal Protocol had prevented the equivalent of over 135 billion tonnes of carbon dioxide emissions — roughly what Canada would produce in 175 years. The treaty has since been ratified by all 198 UN member states and the European Union, making it the first universally ratified treaty in United Nations history. Nearly 99 percent of banned ozone-depleting substances have been phased out. A 2023 United Nations assessment confirmed that the ozone layer is on track to return to 1980 values — before the hole appeared — by 2040 for most of the world, by 2045 over the Arctic, and by 2066 over Antarctica.

The health implications are almost incomprehensible in scale. A 2015 U.S. Environmental Protection Agency report estimated that the Montreal Protocol will prevent over 280 million cases of skin cancer, 1.5 million skin cancer deaths, and 45 million cataract cases in the United States alone. Globally, those numbers are multiples higher. Every strawberry still growing, every coral reef still living, every child still playing in sunlight owes something to the decision made on that September day in Montreal.

Why does this matter to you in 2026? Because the ozone story is the most powerful counter-argument to the idea that global problems cannot be solved. It is direct, measurable proof that when humanity's back is against the wall, we are capable of extraordinary collective action. The scientists were listened to. The polluters were regulated. The alternatives were developed. And the sky began to heal.

The Montreal Protocol also carries an honest lesson. It did not happen automatically. It required decades of scientific persistence, courageous political leadership, and the willingness of industries to adapt. There was illegal production of CFCs in the years that followed. There are ongoing monitoring challenges. The Antarctic ozone hole remains, and it will take until 2066 to fully close. Progress is real — but it has never been inevitable.

I am Henry P., and I believe the Montreal Protocol is one of the greatest stories never fully told. We live under a healing sky today because, in 1987, the world looked at the data, acknowledged the crisis, and chose each other over convenience. In a time when planetary challenges feel impossibly large, this story is not a comfort. It is a contract — proof that we have done the hard thing before, and that we can do it again.

▶ SOURCES

1. United Nations Environment Programme, "Ozone Layer Recovery is on Track," January 2023.

https://www.unep.org/news-and-stories/press-release/ozone-layer-recovery-track-helping-avoid-global-warming-05degc

2. Egorova et al., "Montreal Protocol's Impact on the Ozone Layer and Climate," Atmospheric Chemistry and Physics, May 2023.

https://acp.copernicus.org/articles/23/5135/2023/

3. NOAA Chemical Sciences Laboratory, "2022 Scientific Assessment of Ozone Depletion: Executive Summary."

https://csl.noaa.gov/assessments/ozone/2022/executivesummary/