Saving the Ozone Layer: Our Best Blueprint for the Climate Crisis

You can’t solve a fast-moving problem with slow-moving solutions — but that’s precisely what we’ve been trying to do over 30 years of United Nations climate negotiations. 

To make matters worse, we have failed to move beyond voluntary measures; under the 2015 Paris Agreement, each country decides how much it's willing to do to reduce its climate emissions through so-called Nationally Determined Contributions (NDCs). 

The results are predictably dismal: Since 1990, global warming driven by greenhouse gases (GHG) has increased by nearly 50%, with the summer of 2023 the warmest on record by a wide margin. Fossil fuels are driving the majority of this warming — yet fossil fuels remain “stubbornly high,” comprising 80% of global energy supplies. And the NDCs that have been so far announced will fail to avert increasingly imminent climate catastrophe.

We need a fast-acting mandatory approach — and we need it now. Fortunately, an excellent model exists: the 1987 Montreal Protocol on Substances that Deplete the Ozone Layer, widely acknowledged as the best-ever environmental agreement and ratified by every UN member nation.

Celebrated on Sept. 16, World Ozone Day, it has solved the first threat to the global atmosphere with mandatory measures to phase out production of chemical refrigerants that were destroying stratospheric ozone and letting in excessive ultraviolet radiation that causes skin cancer, eye cataracts and weakens immune systems, while it degrades forests and other carbon dioxide-removing plants. As a result, the protective ozone layer is on the path to recovery by 2066 over Antarctica, by 2045 over the Arctic and by 2040 over the rest of the world.

Meanwhile, it has also done more to avoid warming than any other agreement. This is because the refrigerants are also powerful climate pollutants, thousands of times more potent than carbon dioxide. Phasing them out has already avoided as much warming as is currently caused by carbon dioxide. Leaders should take note: By the end of the century, the Montreal Protocol will avoid a crucial 2.5 degrees Celsius of warming.

Through a 2016 enhancement, the Kigali Amendment, the protocol is also phasing down current refrigerants, which do not attack ozone but are powerful greenhouse gases. This alone can avoid up to a half-degree Celsius by the end of the century. 

There is more the Montreal Protocol can do, including speeding up the refrigerant switch while improving efficiency of air conditioners and other cooling equipment. Efficiency gains can double the climate benefits of switching to climate-friendly refrigerants, avoiding the equivalent of more than 10 years of current carbon dioxide emissions. This is critical in a warming world, where the demand for cooling is growing fast and adding more heating from the extra energy demand, largely supplied by fossil fuels. 

The success of the Montreal Protoco l —which is strongly based on embracing the principle of common but differentiated responsibility, allowing poorer countries to phase out chemicals more slowly and providing adequate funding — has helped keep the planet from a worse climate disaster. Without it, the world would already have crashed through the 1.5-degree Celsius guardrail established in the Paris Agreement, and we would be experiencing some of the irreversible, and almost certainly catastrophic, tipping points that lie in wait beyond that point of warming.

Given its extraordinary success, world leaders should continue to strengthen this climate workhorse. A first step would be for the United Arab Emirates — which is set to host the next round of UN climate negotiations known as COP28 — to ratify the 2016 Kigali Amendment and rally other Persian Gulf states to do the same, a move they are edging closer to doing. It should also rally states to provide incentives to speed up the mandatory replacement of the offending refrigerants and improve the energy efficiency of cooling equipment.

Next, the Montreal Protocol should be used as a model for an agreement to cut methane, the blowtorch pushing the planet from global warming to global boiling. Turning off the flow of methane would avoid nearly three-tenths of a degree Celsius of warming by the 2040s, three times as much as achieved by 2050 from decarbonization alone. COP28 provides the opportunity to launch a mandatory agreement among fossil fuel companies to limit methane emissions to the minimum that technology allows. 

UAE Sultan Al Jaber — the COP28 president, who also heads the state oil company — is well placed to lead negotiations for a binding “Abu Dhabi Agreement to Eliminate Methane Leaks and Prevent Waste of Natural Gas,” having already announced a COP28 goal of near-zero emissions of methane by 2030. This should be supported with a $10 billion a year fund to accelerate methane mitigation from all sectors, including grant funds to develop a pipeline of investable projects, together with contributions from sovereign wealth funds to invest in relevant technologies.

Speeding up the Montreal Protocol’s mandatory measures and negotiating a binding agreement to reduce methane offers the best shot for avoiding the climate reckoning that lies just around the corner. 

Durwood Zaelke is president of the Institute for Governance & Sustainable Development in Washington, D.C., and Paris, as well as an adjunct professor at the University of California, Santa Barbara’s Bren School of Environmental Science & Management. 

Maxime Beaugrand is director of IGSD’s Paris office, focusing on international and EU climate policy and near-term climate mitigation.