The CFC story started in 1974 with the publication by Mario Molina and F. Sherwood Rowland of their conclusion that CFCs were migrating to the upper atmosphere and destroying the ozone layer. The conclusion was initially disputed by industry, but later empirical evidence showed beyond doubt the destruction of the ozone layer. It also showed that the Antarctic ozone hole was caused by the CFCs and related chemicals, a dramatic event that helped galvanize political action. The magnitude of the ozone loss was so unexpected that scientists originally thought their instruments were faulty.
But political action to protect the ozone layer started even before the Antarctic ozone hole was discovered, as citizen consumers in the U.S., Canada, and Europe acted voluntarily to boycott the ubiquitous spray cans—an average of 15 cans in every household—that used CFCs as propellants for hair spray, deodorants, and many other products.
National laws came next, followed by a successful effort to develop an international treaty, the Montreal Protocol, in 1987. The Montreal Protocol parties agreed to cut fifty percent of the first group of CFCs and related chemicals within twelve years. At the next two annual meetings the parties were confident that they could do better and agreed to increase the reduction to seventy-five percent, and then one hundred percent of CFCs, and to move their deadline to ten years rather than the original twelve years. We saw how success truly breeds success.
The Montreal Protocol, now 25 years since its enactment has reason to celebrate: it has reduced nearly 100 damaging chemicals by nearly 100%. Because these same chemicals that destroy the ozone layer also warm the climate, the Montreal Protocol also has made a tremendous contribution to climate protection, nearly twenty times as much as the Kyoto Protocol. This is a planet-saving treaty, protecting both the ozone layer and the climate system. And it can do still more.
This starts with the pending proposals to use the Montreal Protocol to phase down production and use of hydrofluorocarbons (HFCs) that have high global warming impact. HFCs do not destroy the ozone layer, but some of them are super greenhouse gases that are now being used as substitutes for CFCs and the other chemicals being phased out under the Montreal Protocol. Because of the growing demand for air conditioning and refrigeration in a warming world, HFCs are the fastest growing climate warmer in the U.S. and elsewhere, growing globally at ten to fifteen percent per year.
The first proposal to do this was made by low-lying islands, led by the Federated States of Micronesia. This was soon followed by a similar proposal from the U.S., Mexico, and Canada.
Today, 108 countries have expressed their support in a declaration under the Montreal Protocol. If they can overcome opposition from China and India, where most of the future growth in the high impact HFCs will occur, the Montreal Protocol will be able to provide what is a truly significant climate mitigation in the short-term, providing an essential complement to the mitigation we must achieve from reducing carbon dioxide emissions, the key climate pollutant controlling the Earth’s long-term temperature.
If India and China prevent the majority of Montreal Protocol parties from moving forward, the world will miss a vital opportunity to provide near-term climate mitigation and to significantly slow the rate of warming.
A more fitting culmination of 25th year of the world’s most successful environmental treaty would be an agreement to phase down the high impact HFCs when the parties meet later this year, and again provide broader political momentum for additional action to address the accelerating impacts of climate change.
Molina is professor, Department of Chemistry and Biochemistry, University of California, San Diego and shared the Nobel Prize in Chemistry in 1995 for his work on stratospheric ozone.
Zaelke is president, Institute for Governance and Sustainable Development, Washington, DC and Geneva and co-director, program on governance for sustainable development, Bren School of Environmental Science & Management, University of California, Santa Barbara.