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Dual benefits ozone protocol: protecting Ozone layer and Climate

Press release; 5 March 2007 The Netherlands Environmental Assessment Agency

The 1987 Montreal Protocol - restricting the use of ozone-depleting substances - has helped to both reduce global warming and protect the ozone layer. Without this protocol, the amount of heat trapped due to ozone-depleting substances would be double that of today. The benefits to the climate, achieved by the Montreal Protocol alone, at present greatly exceed the initial target of the Kyoto Protocol. This is shown in research led by the Netherlands Environmental Assessment Agency, which will be published this Monday in Proceedings of the National Academy of Sciences (USA). The effects of the Montreal Protocol on the climate will decrease in the future, while emission reductions after 2012 under the Kyoto Protocol will potentially have a much larger effect on the climate.

Antarctic ozone hole

Chlorofluorocarbons (CFCs) and other ozone depleting substances are now globally recognized as the main cause of the observed depletion of the ozone layer. In 1974, Molina and Rowland provided an ‘early warning’, when they first recognized the potential of CFCs to deplete stratospheric ozone. Concern was further heightened in 1985, by the discovery of the ozone hole over Antarctica. The 1987, the Montreal Protocol on Substances that Deplete the Ozone Layer formally recognized the significant threat of ozone-depleting substances to the ozone layer and provided a mechanism to reduce and phase-out global production and use of these compounds. According to research the ozone layer is currently starting to recover.

Greenhouse gases and the Kyoto Protocol

Ozone depleting substances also contribute to the radiative forcing of climate change. Their current contribution is about 20% of that of carbon dioxide (CO2). The Kyoto Protocol of 1997 is a global treaty to reduce the emission of CO2, the leading greenhouse gas, and five other gases. These gases do not deplete the ozone layer. However, the substances that do, are not included in the Climate Convention and its
Kyoto Protocol. 

Dual benefits 

According to research led by the Netherlands Environmental Assessment Agency, the Montreal Protocol has helped to both reduce global warming, and to protect the ozone layer. Without the reductions achieved under this Protocol, the amount of heat trapped due to ozone-depleting substances would be about double that of today. This has meant a gain of about 10 years of CO2 reductions. The climate benefits which are already achieved by the Montreal Protocol alone, are far larger than the reduction target set for the first commitment period of the Kyoto Protocol. However, these climate benefits due to the Montreal Protocol, will reduce further and further, as ozone depleting substances are being phased-out.

Future benefits

New measures under the Montreal Protocol, can result in additional, significant climate benefits, compared to the Kyoto Protocol reduction target. These new measures consist of removing CFCs present in existing applications (refrigerators, foams), and of limiting the production of not fully halogenated fluorocarbons (HCFCs), and/or of implementing the use of alternative gases with lower global warming potentials. Also, additional emission reductions after 2012 are being negotiated in the framework of the Kyoto Protocol. Such reductions have a potentially much larger effect on climate than those of the Montreal Protocol.

Dual benefits Montreal Protocol: protecting Ozone layer and Climate

Dual benefits Montreal Protocol: protecting Ozone layer and Climate

Dual benefits Montreal Protocol: protecting Ozone layer and Climate


Climate Benefit of Montreal Protocol is 5 to 6 Times Larger than 1st Commitment Period of Kyoto Protocol


WILMINGTON, Del., March 5, 2007 - DuPont today reinforced the findings of a group of leading scientists that show the Montreal Protocol treaty has had a significant impact on protecting the Earth’s climate, as well as its ozone layer.

The article, "The Importance of the Montreal Protocol in Protecting Climate," was published today in The Proceedings of the National Academy of Science. Its authors are Guus J.M. Velders, Stephen O. Andersen, John S. Daniel, David W. Fahey and Mack McFarland, DuPont chief atmospheric scientist.

Dr. Mack McFarland, DuPont chief atmospheric scientist

Dr. Mack McFarland, DuPont chief atmospheric scientist, is a leading industry expert on climate change. A former scientist with the National Oceanic and Atmospheric Administration, he is one of the authors of an article stating that the international Montreal Protocol treaty benefitted the Earth's climate, as well as its protective ozone layer.

The Montreal Protocol on Substances that Deplete the Ozone Layer was signed in September 1987. It restricts the use of ozone-depleting substances, including chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), which also are greenhouse gases. After two decades, the treaty has led to substantial reductions in the emissions of ozone depleting substances. Research indicates that the ozone layer is now recovering.

“The Montreal Protocol has had a significant impact in reducing the amount of greenhouse gases that otherwise would have been emitted to the atmosphere,” said Dr. McFarland. “The swift adoption of CFC alternatives in a seamless industry transition during the 1990s, combined with not-in-kind technologies and conservation measures, has contributed to protection of both the ozone layer and the global climate. More than anything, the example set by the Montreal Protocol clearly shows that international cooperation among all stakeholders, with flexible regulations that stimulate innovation, can lead to rapid progress toward protection of the global environment.”

DuPont advocates an accelerated phaseout of HCFCs, actions to minimize emissions of refrigerants and adoption of low global warming potential (GWP) alternatives, where possible. Last year, the company announced the identification of a low GWP refrigerant for auto air conditioning applications and is currently working on leveraging this low GWP technology to other refrigerant applications.

DuPont led the industry in the phaseout of CFCs and transition to environmentally acceptable alternatives. At the time, DuPont estimated that more than $135 billion of existing equipment in the United States alone depended on CFCs, including more than 150 million automobiles, 69 million home refrigerators and more than 70,000 building air conditioning systems. In January 1991, DuPont was the first company to launch a family of refrigerant alternatives that met performance, safety and environmental criteria and could be used in existing as well as new equipment, thus minimizing the transition cost to thousands of businesses and consumers around the world.

DuPont has reduced greenhouse gas emissions more than 70 percent since 1991, with $3 billion in avoided energy costs. Those energy savings are based on the use of improved process controls; optimization of energy generation and distribution at its facilities; new technologies with lower energy consumption, and; one of the biggest factors – improved yields from DuPont’s manufacturing processes. DuPont also is reducing the use of fossil fuels by employing alternative energy sources such as landfill gas.

DuPont – one of the first companies to publicly establish environmental goals 16 years ago – has broadened its sustainability commitments beyond internal footprint reduction to include market-driven targets for both revenue and research and development investment, like low GWP refrigerants. The goals are tied directly to business growth, specifically to the development of safer and environmentally improved new products for key global markets, including products for it customers, like low GWP refrigerants that reduce greenhouse gas emissions.

DuPont is a science-based products and services company. Founded in 1802, DuPont puts science to work by creating sustainable solutions essential to a better, safer, healthier life for people everywhere. Operating in more than 70 countries, DuPont offers a wide range of innovative products and services for markets including agriculture and food; building and construction; communications; and transportation.