Ozone miracle

A collection of climate stories mostly

Photo by img.ly on Unsplash

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 (CFC) compounds were causing the ozone depletion. These compounds were commonly found in fridges, polystyrene manufacture and a propellant for aerosol cans.

Whilst not proven, they believed that the CFCs released into the atmosphere were being broken down by high-energy UV radiation. This in turn, released chlorine and bromine radicals that were tearing up the ozone.

The scientific community wasted no time forming a consensus. Yes it was the CFC radicals causing the damage. The cold temperatures needed for the chemistry was why ozone depletion had only started to occur over Antartica. But if CFC concentrations continued to rise, the phenomenon could spread and lead to the collapse of the ozone layer completely.

What’s now fascinating is the action some countries took, even before the science was finally ratified.

Australians, who must have been feeling particularly vulnerable, became far more attuned to the environmental impact of global activities and the stark reality that they were one of the largest per capita users of CFCs and halon, (an inert gas found in fire extinguishers). 

Even more surprising, the US banned non-essential uses of these chemicals which included those aerosol propellants. What was going on? This appeared to be the action of a government putting the protection and survival of its citizens before the profits of powerful corporate America.

In 1985, governments adopted the Vienna Convention for the Protection of the Ozone Layer. This created the basis for the Montreal Protocol signed by 46 countries, coming into effect in 1989. 

What was truly remarkable was the uncertainty around how the world was going to adapt to the phasing out of such incredibly useful chemicals.

This was a naysayers paradise and the same arguments were spouted then, which we’re all familiar with today about climate change. 

The science about ozone depletion is uncertain, it’s got nothing to do with humans and it’s far too expensive to fix.

Those arguments proved to be misplaced. 

The science of ozone depletion is now well understood and has stood the test of time. The economic argument was also entirely incorrect. The phasing out of CFCs proved to be so cheap and easy, that it was barely noticed. Everything is still as cold and chilled as it was when CFCs were the preferred chemical ingredient for refrigeration.

By 2008, it became the first and only UN environmental agreement to be ratified by every country in the world. Any concerns about how to solve the replacement argument for destructive CFCs, has been long forgotten.

Today, around 99% of ozone-depleting substances are no longer used, and the ozone layer has begun to regenerate. By the 2060s, the ozone hole is expected to close completely.

Ozone hole over Antartica, courtesy of NASA

More recently, research has revealed just how significant international agreement was back in the 1980s. It has meant an environmental catastrophe has been averted.

An international team of scientists from the UK, US and New Zealand, published a study in Nature several years ago which modelled what would have happened if the world had continued to use CFCs.

In experiments, plants exposed to higher levels of UV radiation become more stunted and can’t absorb as much carbon. Less carbon stored means more carbon dioxide in the atmosphere.

This world-avoided experiment would have seen global air temperatures rise by an additional 2.5C by the end of this century. This in addition to whatever else is now locked in by emissions from all the other greenhouse gases.

So why hasn’t this sensible approach to a significant environmental issue, adopted by every nation, avoiding catastrophe, been repeated with all those other gases causing climate change?

Could it be as simple as even more powerful vested interest?

Big oil and gas companies including BP, Exxon and Shell have spent millions of pounds on delaying tactics, bribing governments to kick climate changing policies into the long grass. Despite all the evidence which now exists, these companies continue to carry on drilling and burning fossil fuels.

We need look no further than COP 28 in Dubai, to know that these companies are currently winning our war, profits before humanity. The president of this next facade is Sultan Ahmed Al Jaber, Minister of Industry and Advanced Technology, for the United Arab Emirates.

His other title is Managing Director and group CEO of the Abu Dhabi National Oil Company.