Freon’s Cool Link to Climate

Quick: What’s the name of the big UN global climate treaty?

If you said the Kyoto Protocol – you’d be wrong. Because it’s a trick question.

Although the Kyoto Protocol is indeed the treaty developed to address the issue of arresting global warming and the climate perturbations that will be spawned by such a growing planetary fever, this treaty has yet to actually accomplish much in terms of putting a brake on warming. Indeed, it hasn’t even gotten the United States to sign on yet, and discussions among active parties to the treaty have been languishing.

The only treaty to have had a big impact on climate is the 20 year old Montreal Protocol, a treaty to which the United States is a signatory. This fabulously successful treaty has fostered a dramatic reduction in the production and use of chemicals that pose a threat to stratospheric ozone. It targets a range of chemicals, mainly chlorofluorocarbons. The best known of these chemicals is Freon, which chills major appliances, from refrigerators to air conditioners.

Most ozone-damaging agents have another nasty property. They serve as very potent greenhouse gases, chemicals that like carbon dioxide, contribute to helping trap solar energy at or near Earth’s surface. This means that chlorofluorocarbons are boffo global warmers. A side benefit of the Montreal Protocol, then, has been its effects on
moderating the planet’s growing fever.

Provisions of the Kyoto Protocol ask that signatory nations collectively reduce their releases of CO2 by some 5 billion tons, notes Durwood Zaelke. He’s director of the secretariat of the International Network for Environmental Compliance and Enforcement.

Actions taken under the Montreal Protocol, by contrast – which is adhered to by 191 nations – have cut emissions of ozone-destroying chemicals by amounts that have the greenhouse-warming equivalence of 135 billion tons of CO2, he observes. These measures have had that impact because some of the regulated ozone-damaging chemicals are literally thousands of times more effective at global warming than CO2 is. Zaelke cites published data from climate analysts indicating that the Montreal Protocol’s ozone-protection measures have delayed the repercussions of global warming by 12 years.

For all that the ozone-protection treaty has done for Earth’s climate, clearly it has not been nearly enough because our oceans and atmosphere continue to warm. But representatives of island nations, which are at special risk of being submerged by rising sea levels associated with global warming, have been big proponents of strengthening the Montreal Protocol. Zaelke, who has been working with them, reports they made huge headways last fall and offered a proposal last Thursday to do even more. Most of these new measures would affect appliances that serve as reservoirs of CFCs.

How cool. More on this tomorrow.

KEEPING COOL Refrigerators, air conditioners, and many other products once used chemicals that not only harm stratospheric ozone but also climate. Phasing out the chemicals’ use has had a major impact on keeping the planet from overheating quickly. iStockphoto

Janet Raloff is the Editor, Digital of Science News Explores, a daily online magazine for middle school students. She started at Science News in 1977 as the environment and policy writer, specializing in toxicology. To her never-ending surprise, her daughter became a toxicologist.

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