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The first time I remember hearing about Ozone, was when it made the headlines in the 1980s. Scientists had discovered a hole in it over Antartica.
Ozone is oxygen with an extra atom. Most of the oxygen in the atmosphere contains two atoms of oxygen (O2) and not the rarer O3.
This chemical oddity is hugely significant and forms an important layer in the earth’s atmosphere shielding humans, plants and animals from the worst effects of ultraviolet (UV) radiation. If it wasn’t for this invisible protective layer encircling us, life on Earth would not exist.
The British Antarctic Survey began measuring ozone concentration above Antartica in the 1950s. It took several decades of further pollutants being released, before scientists discovered an ozone hole, a springtime phenomenon where a complete loss of ozone was regularly occurring. Fortunately the same hole disappeared towards the end of spring and by summer, levels again returned to normal.
I remember the news at the time, sensationalising the impact this might have on Australia, the closest country where people were presumably going to fry. Would it ever be safe again to spend a day at Bondi Beach on Christmas Day?
The resultant ozone thinning there consequently, never exceeded more than 5% of normal levels.
Having detected this alarming recurring hole over Antartica, the scientists at the time, were puzzling over why it was happening and how could it be stopped?
Before the hole’s discovery, the hypothesis was ozone depletion is a slow process occurring at high altitudes over mid-latitudes. But this clearly wasn’t the case. Almost all of the ozone over the Antarctic was being wiped out in a few short Spring weeks.
If this started to happen in those mid-latitudes where a lot of people live, there would be a human catastrophe on a scale never previously witnessed.
The original hypothesis posed by various scientists was chlorofluorocarbon…