The narrative discusses the history of the ozone layer depletion, which was a significant environmental issue in the 1980s. The ozone layer, a protective "belt" around the Earth, was being threatened by human activity, particularly the use of Chlorofluorocarbons (CFCs) and Hydrofluorocarbons (HFCs). These substances were found to be depleting the ozone layer, leading to a significant threat to ecosystems, increased skin cancer rates, and potentially the end of life as we knew it.
In 1985, scientists discovered a massive loss of ozone over Antarctica, with 40% of the layer dissipating, creating a "hole". This was a wake-up call for the world, as the problem was not small and far in the future, but was now and much larger than anyone had imagined. In 1986, Dr. Solomon, an atmospheric chemist, led a team of scientists to Antarctica to investigate the cause of the ozone hole.
The team found that the biggest problem was chlorine from CFCs. These compounds, which were not harmful on the ground, broke down into chlorine when they reached the stratosphere. This chlorine then bound with ozone to make oxygen and chlorine monoxide, which caused a chain reaction that depleted the ozone layer. The long lifetime of CFCs, between 50 and 150 years, meant that every year, the year before's usage was almost entirely still there, leading to exponential build-up.
This led to a global effort to reduce the use of CFCs, which was made official with the Montreal Protocol in 1987. This protocol was the first universal treaty to be ratified, and it listed control measures to reduce ozone-depleting substances. Every country eventually signed the protocol, and since the protocol went into effect in 1989, the consumption of ozone-depleting substances has plummeted.
Today, more than thirty years after the Montreal Protocol was signed, the ozone hole has stopped growing and is now shrinking. By 2065, it is expected to have recovered completely. However, the narrative also mentions that after the CFC ban, the world began using HFCs, which do not deplete the ozone layer but are a potent greenhouse gas that contributes to climate change. In 2016, the Montreal Protocol was amended to include HFCs, and they are now also being phased out. The narrative concludes with a call to keep the focus on climate change and to find practical solutions to the challenges it presents.
1. The ozone layer is a "belt" around the Earth made up of gaseous molecules that protects every living thing by absorbing two types of ultraviolet radiation from the Sun.
2. The ozone layer is fragile and can be threatened by human activities.
3. In 1985, scientists discovered a massive loss of ozone over Antarctica, with 40% of the layer dissipating and creating a "hole".
4. The hole in the ozone layer is caused by chlorine from a man-made compound called Chlorofluorocarbons (CFCs).
5. CFCs are not harmful on the ground, but once they float up to the stratosphere, the Sun breaks them down into chlorine.
6. The chlorine then binds with ozone to make oxygen and chlorine monoxide, causing a chain reaction that destroys more ozone molecules.
7. The long lifetime of CFCs (between 50 and 150 years) means that they build up and destroy the ozone layer exponentially.
8. In 1987, ozone levels had dropped by 50 percent due to the use of CFCs.
9. The Montreal Protocol, ratified in 1989, recognized that world-wide emissions can significantly deplete the ozone layer and result in adverse effects on human health and the environment.
10. The Montreal Protocol listed control measures to reduce ozone-depleting substances and included help for developing countries who need alternative technology and substituting products.
11. The Montreal Protocol was the only universal treaty to ever be ratified and is considered the most successful environmental agreement in human history.
12. Since the protocol went into effect, the consumption of ozone-depleting substances, including CFCs, has plummeted.
13. Today, more than thirty years after the Montreal Protocol was signed, the ozone hole has stopped growing and is now shrinking.
14. By 2065, it is expected to have recovered completely.
15. After the CFC ban, the world began using Hydrofluorocarbons (HFCs), which don't deplete the ozone layer but are a potent greenhouse gas that contributes to climate change.
16. In 2016, the Montreal Protocol was amended to include HFCs, and now they are being phased out too.
17. Climate change is already happening and is considered the most challenging environmental problem.
18. Experts say that we have until 2030 to avoid catastrophe.
19. People are suffering, people are dying, and entire ecosystems are collapsing due to climate change.
20. Unprecedented and even irreversible changes are happening to this planet.
21. It is beyond any doubt that human activity is to blame for climate change.