The Hole in the Ozone Layer: The Lesson the World Needs to Relearn

The ozone layer is one of the most precious structures in Earth’s atmosphere. Invisible to the eye yet essential to life, it acts as a shield that absorbs much of the ultraviolet radiation emitted by the Sun. Without this protection, the risks to human health would be devastating: increased cases of skin cancer, cataracts, genetic mutations, and ecological imbalances affecting everything from the oceans to agriculture. It is hard to imagine life on Earth without this natural barrier, which is why the shock was so great when, in 1985, scientists announced the discovery of a hole in the ozone layer over Antarctica a direct result of human activities.

The Hole in the Ozone Layer: The Lesson the World Needs to Relearn

The origin of the problem lay in chlorofluorocarbons, the well-known CFCs, used in aerosols, refrigeration systems, and air conditioning. When these molecules reached the stratosphere, they destroyed ozone, opening an atmospheric wound that grew year after year. Science, with the technology available at the time, was able to identify the anomaly and alert the world. And the world, surprisingly, responded. In 1987, the Montreal Protocol was signed—an international treaty that mandated the gradual elimination of CFCs and other harmful gases. It was a rare example of global cooperation in which rich and poor countries united around a common goal: saving the ozone layer.

Brazil played an important role in this process. In addition to adopting legislation that restricted the use of ozone-depleting substances, the country participated in technological substitution and atmospheric monitoring programs. The national industry was forced to adapt, replacing harmful gases with less damaging alternatives. This transition was not simple, but it demonstrated that, when there is political will and international support, it is possible to align economic development with environmental preservation. Today, thanks to these measures, the ozone hole is recovering, and scientists estimate that by the middle of the 21st century it may be almost completely closed.

This episode proves that science, when combined with technology and international cooperation, can reverse environmental damage. But it is also a reminder that not all problems have such clear solutions. Unlike ozone, which protects against ultraviolet rays, greenhouse gases act in a different way. Carbon dioxide, methane, nitrous oxide, and hydrofluorocarbons do not destroy the ozone layer, but they trap heat in the atmosphere, preventing infrared radiation from escaping into space. The result is global warming. CO₂ is the most significant due to its volume, but the other gases are even more potent molecule by molecule. And unlike the ozone hole, whose effects are already being reversed, global warming brings irreversible consequences: melting glaciers, rising sea levels, and increasing average temperatures are processes far more difficult to undo.

Here lies the key difference between the two cases. With the ozone hole, there was a clear cause, an identified culprit, and a viable technological solution. With global warming, the causes are multiple, economic interests are deeply entrenched, and the solution requires a radical transformation of the world’s energy matrix. Reaching consensus among nations is increasingly difficult. Countries dependent on fossil fuels resist changes that could affect their industries, while disinformation campaigns funded by vested interests spread doubt about the severity of the climate crisis. In addition, global inequality weighs heavily: developing nations demand climate justice, pointing out that wealthy countries were the largest historical emitters.

The ozone hole stands as a shining example of how humanity can unite to confront an existential threat. But global warming demands even greater courage, as it challenges deep-rooted economic and political structures. The lesson we must relearn is clear: when science and society move forward together, it is possible to reverse mechanisms of planetary degradation. The challenge is to turn this awareness into collective action before the climate clock demands a price too high to pay.

Renato Zimmermann is a sustainable business developer and an activist for the energy transition.

The Hole in the Ozone Layer: The Lesson the World Needs to Relearn