Healing the skies needs urgent action

World Ozone Day, marked every September 16, is often treated as a feel-good environmental holiday. Politicians issue statements, schoolchildren are taught that the “ozone hole” is healing, and headlines celebrate international cooperation. But if that’s all we take away, we miss the deeper lesson. This day is not a pat on the back. It is a sharp reminder that science can drive global action—but only if we listen, legislate, and enforce with persistence.

The 2025 theme, “From science to global action,” strikes at the heart of that story. A generation ago, scientists discovered that everyday chemicals—chlorofluorocarbons in refrigerators, air conditioners, and spray cans—were silently tearing a hole in the stratospheric shield that protects life on Earth. Without the ozone layer, skin cancers would soar, crops would fail, oceans would lose their plankton base, and life would be transformed for the worse. Faced with the science, governments acted. The Vienna Convention of 1985 and the Montreal Protocol of 1987 produced the first universally ratified environmental treaty. Every country signed, alternatives were developed, and funds were mobilised to help poorer nations transition. It was an unlikely triumph of science and diplomacy, and today, scientists confirm the ozone layer is on track to recover to pre-1980 levels by mid-century if
commitments hold.

That success is real—but fragile. It is fragile because chemicals banned on paper can still leak from old appliances or be produced illegally. It is fragile because the very gases chosen as replacements, hydrofluorocarbons (HFCs), turned out to be climate super-pollutants—thousands of times more powerful than carbon dioxide in warming the planet. And it is fragile because climate change itself can interfere with ozone recovery, altering atmospheric circulation and amplifying risks from volcanic eruptions or
other natural events.

The Kigali Amendment to the Montreal Protocol, agreed in 2016, is the next great test. Unlike CFCs, HFCs don’t destroy ozone, but their heat-trapping potential is staggering. The United Nations Environment Programme estimates that phasing them down could prevent up to 0.5°C of global warming by 2100. Half a degree may sound small, but in climate terms it can mark the difference between manageable disruption and widespread catastrophe. That makes Kigali not just a side-note but one of the most powerful climate agreements currently in force.

India’s experience underscores both the progress made and the stakes ahead. Far from being a reluctant participant, India has repeatedly moved ahead of schedule. It phased out chlorofluorocarbons and halons by 2010, well before required. It ensured asthma and COPD patients had uninterrupted access to safe inhaler alternatives during the transition. It trained more than 20,000 refrigeration and air-conditioning technicians to handle new, non-ozone-depleting technologies. By August 2008, India had already stopped producing and consuming CFCs—17 months before the Montreal Protocol required. These are not footnotes; they are reminders that developing nations, often painted as obstacles in climate negotiations, can lead with ambition when supported by fair financing and technology.

India also pioneered the world’s first Cooling Action Plan (ICAP) in 2019. With incomes rising and summers intensifying, the demand for cooling in homes, offices, and cold chains will explode. Without intervention, that demand would overwhelm the power grid, increase greenhouse gas emissions, and accelerate ozone risks through refrigerant leaks. ICAP sets ambitious targets: by 2037–38, reduce overall cooling demand by 20–25%, cut refrigerant demand by 25–30%, and slash energy used for cooling by 25–40%. These numbers are not aspirational slogans; they are rooted in concrete policy pathways—more efficient buildings, passive cooling design, and rapid adoption of low-global-warming-potential refrigerants.

The payoff is already visible. According to India’s Ministry of Environment, Forest and Climate Change, national efforts since 2020 have delivered direct emission reductions equivalent to 42.6 million metric tonnes of CO₂ every year, rising to nearly 77 million metric tonnes annually from 2023 onward. Those figures matter. For comparison, they are larger than the entire annual emissions of some mid-sized industrial nations.

And yet, there is no room for complacency. Weak enforcement of refrigerant disposal, informal servicing practices that allow gases to leak, and the sheer cost of transitioning to new technologies remain real threats. Globally, the illegal trade in banned refrigerants continues, exploiting gaps in monitoring. Without rigorous enforcement and public awareness, the hard-won gains can be eroded.

The story of the ozone layer carries three urgent lessons for today’s battles. First, science must not just be heard—it must drive law. When scientists warned of CFCs, policymakers listened and acted. Compare that to the decades-long delay on climate action, where evidence was contested and misinformation ran rampant. Second, fairness matters. The Montreal Protocol worked because rich nations financed a multilateral fund to help poorer nations adapt. That principle must carry over into climate negotiations. Without climate finance and technology transfer, asking the Global South to leapfrog dirty development pathways is unrealistic. Third, vigilance is non-negotiable. Ozone-depleting substances take years to dissipate; refrigerants continue to leak; atmospheric recovery is slow. Progress is reversible if attention wavers.

Critics sometimes argue that the ozone success is unique, a one-off miracle unlikely to be repeated for climate change. But that view underestimates what was achieved. At the time, CFCs seemed indispensable and cheap. Industries warned of economic disaster. Yet policy forced innovation, costs fell, and alternatives thrived. The same could be true of fossil fuels and high-emission industries today—if political will matches scientific urgency.

Ordinary citizens also have agency. Buying appliances certified as ozone- and climate-friendly, disposing of old refrigerators responsibly, avoiding products with dangerous propellants, and supporting companies that invest in sustainable cooling are small acts with cumulative impact. Farmers can replace methyl bromide fumigation with safer pest-control methods. Technicians can be trained to recover and recycle refrigerants rather than venting them. These everyday shifts multiply when backed by public awareness campaigns and government incentives.

World Ozone Day should not be reduced to a ceremonial marker. It should be a mirror. It shows us that global cooperation works, that science can guide policy, and that even invisible threats high above our heads can be managed when nations unite. But it also shows us the dangers of delay. Had governments hesitated longer, the ozone layer might have collapsed beyond repair.

The skies are healing—but slowly. By mid-century, if commitments are kept, the ozone hole may close. That is cause for celebration. But if the ozone story becomes a comforting tale rather than a call to arms, we risk squandering its most important lesson: global environmental problems can be solved, but only if urgency, fairness, and vigilance endure.

The ozone victory was once thought impossible. The climate crisis is harder, but not unmanageable. Healing the skies was only the beginning. Healing the Earth itself is now our collective task.