What Can We Learn About Driving Systems Change From the Montreal Protocol?

Last month we launched a new paper looking at why systems change is needed to end loss and damage from climate change —and importantly— how we can drive systems change.

In this blog we look at what global ozone recovery under the Montreal Protocol —considered one of the world’s most successful environmental agreements— can teach us about how we might drive systems change, taking into consideration some of the key findings of our new paper.

What is the Montreal Protocol?

The Montreal Protocol on Substances that Deplete the Ozone Layer (Montreal Protocol) was adopted in 1987 in Montreal, Canada, and came into force in 1989. It is a multilateral environmental agreement that regulates the production and consumption of ozone-depleting substances (ODS). The Protocol was created under the 1985 Vienna Convention for the Protection of the Ozone Layer (Vienna Convention) —a framework treaty that set general principles for international cooperation, research, and information-sharing regarding the Earth’s ozone layer.

What was the problem?

In 1985, an ozone hole was identified over Antarctica. Scientists quickly confirmed that this was being caused by human-made chemicals such as chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), and halons, which were being used in applications such as refrigeration, air conditioning, and fire extinguishers. When released into the atmosphere, these ODS were damaging the Earth’s protective layer that shields humans and more-than-humans (e.g plants and animals) from harmful levels of ultraviolet radiation from the sun. If action was not taken, ultraviolet radiation (UV) would have caused a rapid rise in lethal skin cancers and cataracts, devastated agricultural crop yields, and risked the collapse of the marine food web.

What was the solution?

Just two years later, governments signed the Montreal Protocol committing the 197 Parties of the Vienna Convention to protect human health and environment against adverse effects of human-induced changes to the ozone layer.

Since being adopted in 1987 and entering into force in 1989, the Montreal Protocol has successfully phased out nearly 99 percent of ODS. As a result the ozone layer is now on track to fully recover by 2066.

Why was the Montreal Protocol so successful?

The Montreal Protocol is considered to be one of the world’s most successful environmental agreements and remains the only universally ratified treaty. With most ODS being greenhouse gases, the Montreal Protocol has not only addressed ozone depletion but has also helped to avoid carbon emissions equivalent to more than 135 billion tonnes of carbon dioxide (CO₂).

Success is attributed to several factors including:

• The ozone hole could be easily visualised and understood as a problem, the solution is equally easy to comprehend.
• The Montreal Protocol was adopted with the urgency required. Action was taken before scientific certainty was established. Within two years of the discovery of the ozone hole, the Montreal Protocol was negotiated and ratified.  
• The treaty focused on specific chemicals produced by a limited number of industries, making it easier to regulate and monitor.
• The treaty included top-down mandatory phase-outs with legally binding targets.
• The threat of increased UV radiation leading directly to higher rates of skin cancer and cataracts galvanised massive public concern and political will.  
• Industry eventually came to support the treaty as DuPont and other chemical companies producing ODS’ developed commercially-viable substitutes such as hydrofluorocarbons (HFCs).
• The United States of America (U.S.) played the role of a leader, rather than a blocker, including by offering financial incentives to other ODS-producing countries.
• Collaboration between scientists and civil society actors led to a strong environmental movement in the U.S. that catalysed a global network of organisations around a unified campaign to positively influence the negotiations. Tactics including awareness-raising actions that targeted the public and boycotts of products that used ODS (e.g. aerosols) were shared throughout the global network of organisations.
• The treaty established the Multilateral Fund for the Implementation of the Montreal Protocol in 1991, which provided financial and technical assistance to help developing countries phase out ODS. The Fund is financed by developed countries, contributions are mandatory and tied to compliance with the Montreal Protocol. The Fund is governed by equal numbers of representatives from developing and developed countries.
• The treaty established different timelines for developed and developing countries to phase out ODS and allowed flexibility to develop national phase-out commitments.
• Equity-promoting provisions in the Montreal Protocol facilitate cooperation between developed and developing nations and promote shared responsibility for research, technology development, and knowledge sharing. These provisions recognised structural imbalances in power, resources, and capabilities.  
• Inclusive negotiations enabled broad participation across divisions of geopolitical alliances and development status.  
• In September 2007, Parties to the treaty decided to accelerate their schedule to phase out HCFCs —which are both ODS and greenhouse gases that are 2,000 times more potent than CO₂— recognising the benefit this would have in regards to limiting global heating.
  

How has the Montreal Protocol responded to emerging challenges?

In addition to its successful adoption and initial implementation, the Parties that have ratified the Montreal Protocol have continued to act with urgency to address emerging challenges. HFCs were introduced as alternatives to CFCs and HCFCs to support the phase out of ODS. However, HFCs are potent greenhouse gases —with a global warming potential of hundreds to thousands of times that of CO₂— and are expected to make up 7 to 19 percent of global emissions by 2050. In light of this, Parties recognised that they needed to address the global warming potential of HFCs under the Montreal Protocol. This came in the form of the Kigali Amendment to the Montreal Protocol (Kigali Amendment), which was adopted in 2016, in Kigali, Rwanda. The amendment seeks to reduce HFCs by 80-85 percent by 2045, thereby helping to avoid up to 0.5 degree Celsius of global temperature rise by 2100.

What challenges lie ahead?

However, the implementation of the Montreal Protocol and its Kigali Amendment has not been without its challenges. Political hurdles are emerging in the context of wider geopolitical uncertainty and related shifts in national priorities on climate change and environmental protection. This includes the U.S. issuing national regulatory roll-backs under the Trump administration that have loosened compliance deadlines for HFC use in the commercial refrigeration and air conditioning sectors. The UK has also decided to delay plans to tighten regulatory limits on the production, import, and sale of HFCs, citing a lack of viable alternatives to HFCs. The Multilateral Fund also faces challenges, including a potential shortfall in finance and difficulty disbursing funds to fragile States. Scientists have also warned of the potential for other substances and activities to deplete the ozone layer including space travel and debris from satellites, urging continued investment in monitoring.

Therefore, despite the success of the Protocol to date, the recovery of the ozone layer will require Parties to be responsive to emerging challenges—including through new amendments— while ensuring the implementation of the existing commitments. This suggests that the Montreal Protocol will continue to provide valuable lessons, particularly on how to ensure sustained implementation of transformative changes and the importance of responsive governance in the face of new challenges.

What lessons can be taken forward? ‍

The success of the Montreal Protocol suggests several important lessons to take forward in our work on systems change:

1. ‍Urgent action is possible: The rapid response to the ozone hole demonstrates that countries can make decisions quickly in response to warnings from scientists. This suggests the importance of defining science and maintaining expectations for States to act with urgency in line with their obligations under international law (e.g. to uphold human rights and act on climate change). ‍
2. Mandatory phase-outs with legally binding targets work: The pace and scale of the phase-out of ODS demonstrates how legally binding targets help to drive implementation. This suggests that all future agreements should include legally binding targets and mandatory actions—particually when lessons learned from the Paris Agreement’s use of Nationally Determined Contributions (NDCs) instead of legally binding emissions targets are taken into account. ‍
3. Powerful polluting countries should be leading, not blocking: The U.S. that demonstrated leadership on the Montreal Protocol may be a radically different beast to the America that we know today, yet their leadership in the 1980s demonstrates the important role that powerful polluting countries can play in driving change. Had the U.S. blocked the Montreal Protocol, Earth would have faced a collapsed ozone layer, soaring UV radiation levels, widespread ecological damage, and an extra 1°C to 2.5°C of global warming. Although our tough geopolitical times suggests that we should not count on the world's most powerful polluting nations to lead, the emerging importance of coalitions of the willing—such as the States that convened at the Conference on Transitioning Away from Fossil Fuels in Santa Marta, Colombia, in April 2026— suggest committed coalitions of States and embracing plurilateralism will help to drive positive tipping points.  ‍
4. Strong conflict of interest policies are needed to prevent corporate capture: Although industry eventually supported the Montreal Protocol, chemical companies did so on their own terms and only after they had developed commercially-viable substitutes for ODS that would ensure they continued to profit. When considered alongside evidence of the significant influence of corporate actors from the oil and gas and agricultural sectors on UNFCCC negotiations, it becomes clear that robust conflict of interest policies are required to prevent industry from shaping international agreements based on their priorities.  ‍
5. A strong civil society movement will drive change: A global network of civil society actors played a significant role in pushing their governments to adopt the Montreal Protocol. Research has since affirmed that non-violent protests are twice as likely to succeed as armed conflict, with those engaging a threshold of 3.5 percent of the population having almost never failed to bring about change, while only 20-25 percent of a population is typically required to reach a positive tipping point.‍
6. Funding for implementation in the Global Majority with mandatory contributions from the Global Minority is key: The important role that the Multilateral Fund for the Implementation of the Montreal Protocol played in securing the agreement and driving implementation clearly demonstrates the importance of finance. This, alongside lessons learnt about the significant implications of Global Minority countries failure to deliver climate finance, suggests that transformative change is not possible without means of implementation, and the need for mandatory contributions to ensure commitments are followed through. Research shows that Global Minority countries can raise at least 6.6 trillion USD each year from innovative sources that won't burden the average taxpayer to meet their finance obligations (e.g. through a Climate Damages Tax).    ‍
7. Equity that recognises structural power imbalances is key to promoting international cooperation: By enshrining equity-promoting provisions, the Montreal Protocol facilitated greater international cooperation to tackle the ozone hole while recognising that Global Majority countries need longer and more support to take action. This suggests that all future agreements must include similar equity provisions, to ensure implementation and that States act in-line with their respective capacities.  ‍
8. Responsive governance can ensure that new challenges are addressed: Parties' decisions to tackle HFCs with the Kigali Amendment demonstrates how responsive governance can address emerging challenges. Given the unknown risks associated with tipping points and casting impacts, responsive governance will play a critical role in amending existing commitments to address new challenges —and where this is not possible— taking urgent action to put in place new agreements.  
9. ‍Targeted regulation of individual pollutants and activities could help to drive positive tipping points: Unlike for climate change, the challenge related to novel entities, and other types of overshoot, just a few companies and products were responsible for ODS. Therefore we could argue that a large part of the Montreal Protocols success is due to the limited number of chemicals and industries that needed to be monitored and regulated to fix the ozone hole. This suggests that a sectoral approach to overshoot could be taken to complement and enhance ambition under existing treaties. Research suggests that targeted regulation of individual pollutants and activities (e.g. private jet travel and cement production) that make significant contributions to ecological overshoot and social shortfalls (e.g. inequality and a lack of access to health care) will have near term benefits and could lead to positive tipping points. For example, reducing emissions from short-lived climate pollutants, particularly hydrofluorocarbons, methane, and black carbon, can avoid up to 0.6 °C of global warming by 2050 and will have significant health benefits (e.g. by reducing respiratory diseases). However, these efforts must not distract from tackling the root causes of ecolocal overshoot and social short fall, particularly the need for a fast, fair, full, and funded phase out of fossil fuels. Emerging multilateral and plurilateral efforts to tackle individual pollutants include negotiations to produce a legally binding agreement on plastics, the Climate and Clean Air Coalition efforts to cut black carbon, the Global Methane Pledge, and over 90 countries banning single use plastics.  

What are the limits to what we can learn from the Montreal Protocol?

It is important to acknowledge that there are limits to what can be learnt from the Montreal Protocols success due to its narrow scope. In the context of driving truly transformative systems change, the Montreal Protocol ultimately fails to address the root causes that have led to ozone depletion including unsustainable consumption and growth, with Parties instead choosing to implement false solutions such as HFCs that contribute to overshoot of other planetary boundaries. The Protocol also fails to address the harm caused by the extraction of resources that are required in the production of ODS and neglects the waste created by the phase out of ODS (e.g. fridges). However, much can still be learnt from the success of the Montreal Protocol, and perhaps most importantly, it provides a much needed example of how multilateralism can address ecological overshoot and social shortfalls.  

Join us

This new paper and its findings mark the beginning of an important body of new work for the Loss and Damage Collaboration (L&DC). Our new workstream on systems change will focus on considering what systems change entails and identifying opportunities to advance transformational change that addresses the root causes and drivers of ecological overshoot and social shortfalls.

For more information on how to collaborate with us on this work by reaching out to us via: info [@] lossanddamagecollaboration.org