Usually, in the stratosphere of our atmosphere, the air is not very cold. At the starting point, the average temperature is -51° Celsius. And at the top, the average temperature is -15° Celsius. After this, the temperature increases only when the height increases. This is why Antarctica was the most vulnerable to this threat.
But the good news in this story is that politicians took immediate action. After this finding in 1985, the next year, in 1986, the United Nations began negotiations on it. They started drafting a treaty to ban CFCs all over the world. In 1987, a Montreal Protocol was formed, which came into force in 1989. The amazing thing was that this became the first United Nations treaty in global history, which was signed by every country. All 198 member countries of the United Nations ratified this treaty.
Because of this, CFCs were replaced by HFCs, Hydrofluorocarbons, which had no negative effect on the ozone layer. In the 1990s, these nations started taking action and the use of CFCs declined. Still, in 2000, the largest ozone hole was discovered, which was almost spread over 30 million km². This is because there’s a delay between taking action and seeing its impact. But positive results were seen soon. The global CFC consumption was 800,000 metric tons in the 1980s. By 2014, it fell to only 156 metric tons. 99% of the CFCs were eliminated collectively by all the countries.
