Finding Hope in the Montreal Protocol
Given all the regulatory rollbacks that will allow for more climate changing greenhouse gases to be pumped into the atmosphere and to the attempt to overturn the endangerment finding currently in progress, the International Day for the Preservation of the Ozone Layer (September 17th) is a welcome reminder of a time when nations came together to successfully solve a global environmental problem. As the UN’s “International Day for the Preservation of the Ozone Layer” site proclaims: “The ozone treaties have epitomized the concept of moving from Science to Global Action. And they will do so for many years to come.”
What is the ozone layer, and why is it important?
The ozone layer is located in the stratosphere and screens out harmful UV radiation that would otherwise hurt humans and other life on earth. The UV filtration provided by the ozone layer lowers our risk of skin cancers and cataracts and also prevents damage to plants and lowered crop yields.
Why does the ozone layer need to be preserved?
British scientists discovered a “hole” (an area of extremely low levels of ozone) in the ozone layer over Antarctica in 1985 that was caused by human made chemicals — mainly chlorofluorocarbons (CFCs).
I’m confused: isn’t ozone bad?
Though ozone in the stratosphere and ground-level ozone is the same molecule made of 3 oxygen atoms (O3), ozone in the stratosphere is created by oxygen (O2) being broken apart by incoming UV radiation into single oxygen atoms, which are then forced into groups of three oxygen atoms, thus making ozone. This ozone, high above the layer of air we breathe, protects us from the radiation that helps create it.
Ground level ozone, on the other hand, is created by chemical reactions between oxides of nitrogen (NOx) and volatile organic compounds (VOCs) in the presence of sunlight. These NOx and VOCs are produced by industrial facilities, power plants, motor vehicle exhaust, and chemical solvents. Breathing ground-level ozone can cause asthma and other respiratory diseases, reduce lung function, and increase the risk of other illnesses. It also damages plants and ecosystems.
What was done to preserve the ozone layer?
Once scientists established the connection between the depletion of the ozone layer and the release of CFCs and other ozone depleting chemicals (ODC), the international community came together first to establish an international mechanism that would allow countries to work together to solve the problem and then, in 1987, to draft and agree on the Montreal Protocol, which phased out CFCs and, importantly, had a clause that would allow the treaty to later ban ODCs that had not yet been invented. To this day the Montreal Protocol is the only UN Treaty that has been ratified by all countries in the world.
Has the Montreal Protocol been successful?
According to a 2022 assessment, the ozone layer is expected to return to levels of ozone observed in 1980 (before the appearance of the hole) by the middle of this century.
Other benefits of phasing out CFCs:
CFCs are also potent greenhouse gases. Thus, NOAA estimates that phasing them out avoided a potential additional temperature increase of 0.5 to 1 degree Fahrenheit by 2100.
Doesn’t the success of the Montreal Protocol indicate we can come together to solve climate change?
Not necessarily. It might seem like the Montreal Protocol could serve as a model for a climate agreement, given its success. After all, both the “hole” in the ozone layer and the climate crisis are caused by chemicals released into the atmosphere. But there are critical differences in the two problems and what it takes to solve them.
- The Montreal protocol was agreed on at a much less divisive time
- The current US administration either doesn’t acknowledge climate change, or acknowledges it but denies we are causing it and thus insists we have no role in mitigating it, or says it’s a good thing because all that CO2 will benefit plants (a huge oversimplification).
- As Daniel Cohan, Ph.D. points out in his book Confronting Climate Gridlock, the chemicals that needed to be phased out to protect the ozone layer were produced by a few chemical companies, and these ODCs were a negligible part of their overall business. Fossil fuels, the burning of which produces the greenhouse gas CO2, on the other hand, account for about 80% of energy use globally and are a pervasive part of our culture. Further, substitutes for CFCs were easily and quickly created, whereas, immediate replacements for fossil fuels are not so readily available.
Can the success of the Montreal Protocol give us hope that we can successfully address the climate crisis?
Climate change cannot be solved with a quick fix or a single treaty. Unlike mitigating ozone depletion, which entailed phasing out a relatively narrow group of chemicals that had readily available alternatives, addressing climate change will impact nearly every part of the global economy and will require significant changes to all aspects of our lives.
However as a demonstration of the ability of the nations of the world to act on science, act quickly, and act unanimously to solve a global problem – YES, the success of the Montreal Protocol can give us hope and encourage us to continue to push for climate action and to expect our leaders to work together with each other and with other nations on climate change and other global challenges.
References and Resources:
Cohan, Daniel S., Ph.D. Confronting Climate Gridlock: How Diplomacy, Technology, and Policy Can Unlock a Clean Energy Future. New Haven, CT: Yale UP, 2022.
https://www.epa.gov/ozone-
https://www.epa.gov/ozone-
https://www.epa.gov/ozone-
https://www.noaa.gov/news-
https://ozonewatch.gsfc.nasa.
https://www.tceq.texas.gov/