Earlier this week we heard the sad news that the man who discovered the ozone hole, Joe Farman, has died. I’m sure you all know what the ozone layer is and what the issue with the hole was, but just as a quick reminder… The ozone layer is an area of the earth’s stratosphere that contains a higher percentage of ozone (O3) than the rest of the atmosphere – this percentage is still incredibly small (1 part per 100,000 – that means that for every 1 ozone molecule there are 99,999 molecules of other gases), but these tiny tiny molecules, even in very low concentrations, have an amazing power to trap certain types of sunlight and stop them from reaching Earth. Luckily for us, those wavelengths of sunlight are some of the most dangerous ones.
Dr Farman first co-wrote a paper (scientists write articles in special magazines called journals when they think they have discovered something interesting) in 1985 about a hole in the ozone layer that he had detected over Antarctica. For years afterwards everyone was talking about the ozone layer and what a problem is was, and they were right. If the ozone layer stopped covering the Earth it would be nothing short of a disaster, not only for our species but also for many others.
We don’t hear so much about the ozone layer these days, and the reason for that is one of the major successes that environmental and government campaigning can claim. A large part of what was causing the problems in the ozone layer was down to chemicals called CFCs, amongst other things. These CFCs were able to set off chain reactions which broke down ozone molecules while not being altered themselves (this is known as a catalyst) which means that every CFC molecule is capable of removing many many ozone molecules from the atmosphere. CFC production slowed down dramatically after the discovery of the hole in the ozone layer and they were totally banned in the developed world in 1995.
Unfortunately due to their nature, CFCs can stay in the atmosphere for decades, causing more harm, but because of the ban the speed at which the ozone layer is being lost has slowed down, and in 2009 the World Meteorological Organisation (WMO) said that the hole in the ozone layer was smaller than it had been in 2008, which is great news (although weather can greatly influence the size of the hole, so it may not be quite as brilliant as it sounds). In the same report the WMO predict that the hole will fully recover by 2075 at the earliest.
The points we’d like to make about all of this are that, in publishing his discovery of the hole in the ozone layer, Dr Farman helped to change attitudes for the greener and raised public and governmental awareness of a massive issue. The second point is that through public awareness and legislation it has been possible to slow and hopefully begin to reverse a catastrophic piece of environmental damage. That’s why we don’t hear about it so much these days. That’s why the campaigning was worth it.
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Blog post by Linda Seward of Seward Technical Writing, providers of original science content.