Our thinking

Humanity healed the Ozone hole

13 January, 2023

Older readers will remember deep concern over the hole in the ozone layer that was first identified in the mid-1970s. Efforts to address the issue led to the Montreal Protocol in 1987. Countries began to implement legislation phasing out chlorofluorocarbons (CFC) and other ozone depleting substances (ODSs). And according to a recent report, the ozone layer could be completely restored by 2040. This is not only great news, by any analysis, but also a great example of how global agreements can have positive, lasting impacts.

CFCs and ODSs are potent greenhouse gases meaning that the Montreal Protocol has played a role in limiting climate change, as well as protecting the ozone layer (although it should be said that CFC replacements such as HFCs are actually much more potent greenhouse gases than CFCs. Fortunately the Montreal Protocol continues to be updated and enforced to this day). While reducing CFCS and ODSs was relatively easy (a small number of causes, the opportunity to transition to alternatives at a reasonable cost), reducing CO2 emissions to the extent needed will be considerably more challenging. Greenhouse gases come from many different sources, and the systems that drive climate change are complex. Many different sectors are involved, as opposed to just a few. And of course, the more complicated a problem, the more difficult the solution is likely to be.

However, lessons can be learnt from the Montreal Protocol and perhaps serve to highlight a way forward to meeting the ambitions of the Paris Agreement on climate change. One is the ability to respond to new scientific knowledge, as it emerges, by updating targets and increasing the level of ambition. Another is about the importance of addressing climate change on a sector by sector basis. And yet another is about the need to constantly revisit and refresh our ambitions and to continue to push for scientific innovation and progress on all fronts.

If we want to achieve the goal of keeping global warming to well below 2°C while pursuing efforts to limit it to 1.5°C, we will have to match the Montreal Protocol’s success in drastically upping our ambition over time and accelerating the implementation of measures to achieve those goals. It’s a big ask, but the Montreal Protocol lights a way forward.

By Ash Werner