Hannah Ritchie: How We Fixed the Ozone Layer→

Works in Progress

Ozone levels stabilized in the 1990s following the Montreal Protocol, and have started to recover. They are projected to reach pre-1980 levels before 2075.

“When it comes to stories of progress, there aren’t many environmental successes to learn from. We’ve seen massive improvements in many human dimensions in recent decades – declines in extreme poverty; reductions in child mortality; increases in life expectancy. But most metrics that relate to the environment are moving in the wrong direction. Although there are some local and national successes – such as the large reductions in local air pollution in rich countries – there are almost none at the global level.

Yet there is one exception: the ozone layer. Humanity’s ability to heal the depleted ozone layer is not only our biggest environmental success, it is the most impressive example of international cooperation on any challenge in history...

Our efforts to tackle other environmental problems have not been quite so successful. Can we extrapolate any of the lessons from the task of fixing the ozone layer to other challenges, such as climate change?

There are of course many similarities: ozone depletion and climate change are shared, global problems. Unlike air pollution where local residents are impacted by local emissions, it is the entire global population that is impacted by ozone depleting substances and greenhouse gas emissions. This is because these gases disperse easily across the globe; they are known as ‘well-mixed’ gases. The need for international coordination on both issues is therefore obvious.

We can also learn from the ramping up of efforts over time. The ambition of the first Montreal Protocol in the 1980s was far too weak to solve the problem. Although it was better than ‘business as usual’, the target would have meant that the ozone hole would have continued to expand. Our efforts were only successful because we continued to raise the standards of regulation over time. Climate policy is in a similar position today, and has been for a long time.”

Fred Pearce: Solving the Ozone Problem→

Yale360:

“Did the Montreal Protocol fix the ozone hole? It seemed so. With chlorofluorocarbons (CFCs) and other ozone-eating chemicals banned, many scientists said it was only a matter of time before the ozone layer recharged, and the annual hole over Antarctica healed for good.

But 30 years on, some atmospheric chemists are not so sure. The healing is proving painfully slow. And new discoveries about chemicals not covered by the protocol are raising fears that full recovery could be postponed into the 22nd century – or possibly even prevented altogether.

In mid-September, the United Nations is celebrating the protocol’s 30th anniversary. It will declare that “we are all ozone heroes.” But are we patting ourselves on the back a bit too soon?

The ozone layer is a long-standing natural feature of the stratosphere, the part of the atmosphere that begins about six miles above the earth. The ozone layer filters out dangerous ultraviolet radiation from the sun that can cause skin cancer and damage many life forms. It may have been essential for the development of life on Earth.”