A stunning report came out in this week's Proceedings of the National Academy of Sciences (PNAS): "The importance of the Montreal Protocol in protecting climate." The Montreal Protocol, signed in 1987 by virtually every nation on the planet, including the U.S., sought curbs on the production of stratospheric ozone-destroying chemicals such as the chlorofluorocarbons that were ubiquitous in air conditioners until that time. The new report says the ozone-layer protecting agreement was responsible for a 50% cut in the amount of greenhouse warming that would have occurred by 2010 had these substances continued to build unabated in Earth's atmosphere. The amount of warming that was avoided is equivalent to 7 to 12 years of an increase in carbon dioxide concentrations in the atmosphere.
The critical action was taken because of the pioneering work of Paul J. Crutzen, Mario J. Molina and F. Sherwood Rowland. They were awarded the Nobel Prize in 1995. The work of these scientists catalyzed a worldwide popular environmental movement to ban CFC-containing aerosol containers and then the CFC's in air conditioners. One of the several interesting and amazing things about this landmark agreement is that it was driven by science and a very potent grassroots call for change. The parallels to the growing movement to address and fight climate change are there for us to see and appreciate.
It seems clear to me that when people are armed with enough good information, they will act in good faith and for positive change. This was how the modern American civil rights, women's rights, and environmental movements all progressed. We've come a long way, baby, in these movements. It looks as if the cause of defeating the global warming that threatens Gaia is rapidly building a good head of steam too. But thank heavens for the inadvertent boon to controlling warming engendered by the movement to protect the stratospheric ozone.
P.S. An article by Keith Bradsher in the "NY Times" on February 23, 2007, reported on serious backsliding on curtailing the use of ozone-destroying chemicals. See "The Price of Keeping Cool in Asia; Use of Air-Conditioning Refrigerant Is Widening the Hole in the Ozone Layer."
Update: Bradsher further reports on March 15 that a coalition of developed and developing countries, including the U.S., Argentina and Brazil, are calling for an accelerated phaseout of the ozone-destroying refrigerant, HCFC-22. The article says: “An accelerated phaseout of the refrigerant could speed up by five years the healing of the ozone layer of the atmosphere. It could also cut emissions of global-warming gases by the equivalent of at least one-sixth of the reductions called for under the Kyoto Protocol.”