I explained in Blog 9 that something went horribly wrong. Mankind had managed to jeopardize the health of the ozone layer in the stratosphere that protects us against harmful UV radiation. The most striking phenomenon occurring was the yearly formation of the ‘hole’ in the ozone layer above the continent of Antarctica.

What happened next may be described as monumental. The world came together and started, with unprecedented speed, decisively investigating how to optimally resolve this problem. An intent in which we succeeded.
In this blog I share the good story.

Only 12 years after the first reporting on the presence of halons in the atmosphere (Lovelock, 1973) and 11 years after the first published paper about the fact that these manmade molecules were threatening the ozone molecules in the ozone layer (Rowland and Molina, 1974), the framework on how phase-out of production and consumption of ozone depleting substances could be realized, was drawn up at the Vienna Convention in 1985. Two years later, on September 16th 1987, the Montreal Protocol was signed in which this proposal was consolidated. The Montreal Protocol is to this day the only treaty that has been signed by all countries in the world. Moreso, while all European Union members have signed individually, the EU has also signed as independent body. The fact that we were eager to sign twice illustrates the tremendous enthusiasm of wanting to be part of this club, and more importantly part of this history.

The ozone depleting substances have been split it different classes in the Montreal Protocol. The compounds that belong to the first class (mainly substances with high ozone depleting potential) are required to be phased out quicker than the substances categorized in the second class (mainly substances with a lower ozone depleting potential). To elevate the chance of success of this global transition to the use of alternative substances, different timelines were set up for developed and developing countries. The latter received some more respite. The ultimate goal of the treaty is to restore the concentration of ozone in the ozone layer to the unaffected levels from before 1980.

This is big. Let me put it in perspective.
In 1987, at the moment of decision, there were no negative consequences for the human race visible or measurable. Based on models and scientific evidence policy makers however understood that the problem needed handling. Action and change were required. There was a collective sense of urgency and it was acted upon.
Hats off for that.

Nowadays it seems like we cannot reach the same type of consensus. Even when consequences are already measurable, visible and palpable, courageous decisions (or the execution of them) fail to come through. Can we kindly encourage all stakeholders to repeat the Montreal Protocol’s magic once again?

The actions taken in the Montreal Protocol are leading us to the desired result.
The ozone layer is recovering.
It is prospected that by 2040 the ozone concentrations in the stratosphere, with the areas above the poles as an exception, will be restored to their pre-1980 concentrations. From 2066 onwards there will be no yearly hole formation above Antarctica anymore.

You might wonder why it is taking so much time. Even though the consumption of ozone depleting substances has been reduced with 99.7% compared to its consumption levels in 1990 and we are thus only bringing a very small fraction of new pollution into the atmosphere (mostly of class 2 substances, the ones with lower ozone depleting potential), the inflicted issue is not immediately resolved now the source problem has been addressed. Halons have, as mentioned in blog 9, an annoyingly long lifespan. Consequently, there are ozone molecules in the ozone layer today that are being destroyed by chloride and bromide radicals originating from molecules that we let escape into the atmosphere over 50 years ago.
We will have to sit this one out for a while. There is no quick-fix.

It is however worth the wait. We have avoided a tragedy.
Models calculate that, without the Montreal Protocol, the ozone layer would have been omnipresent by 2040 meaning that the concentration of ozone would be everywhere, year round, below the historical minimum of 220 DU. At noon, in our regions, the UV-index would rise to 15. For comparison, UV-index of 10 is catalogued as ‘extreme’ which basically means: stay inside. Without measures taken it is estimated that there would have been 2 million additional deadly skin cancer cases each year from 2030 onwards.
These are only some of the direct consequences to humans. Our fauna, flora and climate would have taken many blows, leading to also far-reaching consequences for us.

May it thus be clear that we were right to act.

And then there is something else.
The Montreal Protocol contains an interesting clause. It is set that the conditions of the treaty may be modified or elaborated upon when new (scientific) information becomes available. Of the different modifications made between 1987 and now, the Kigali Amendment is probably the most notable one. On September 16th 2016 it was decided to start the phase-out of hydrofluorocarbons (HFC’s). These components had been initially introduced as acceptable alternatives for the ozone depleting substances considering they do not fall under this category. It are however strong greenhouse gases which leads to the logical decision to move towards more environmentally friendly substances to keep our refrigerators cooled.
This is remarkable. A modification has been implemented to the ‘Montreal Protocol on Substances That Deplete the Ozone Layer’ that restricts chemical compounds that do not – in any way – affect the health of the ozone layer. The scope was thus broadened and we can only applaud that. The consistent execution of this amendment will namely prevent an additional 0.4 °C heating of this planet by the end of the century.
Not just a tiny detail.

This success story is to me, apart from the obvious win of diverting a worldwide disaster, also of other value. It indicates the possibility. The sequence of events and actions that led to and followed the Montreal Protocol show that, when science, politics and industry unite to reach a consentient decision and then consistently execute the agreed upon arrangements, we are capable of tackling major global challenges. My heart skips a beat, of happiness and hopeful anticipation, when I think of such solidarity and decisiveness and to what its reproduction can lead us once again.
I wonder, does it have the same effect on you?