Due to temporary compatibility problems, the BC Atmosphere Caucus could not bring you it's own information on current ozone depletion. The fax sheet you are about to read is courtesy of the EcoGopher at the University of Virginia, and has been updated by the BC Atmosphere Caucus. This fact sheet was prepared with the assistance of the Environmental Defense Fund. Fred Krupp, EDF's Executive Director, is a member of Earth Day 1990's Board of Directors. The introduction was provided by the BC Atmosphere Caucus. ************************ Ozone depletion is said by many to be the most serious environmental problem that we must currently face. Ozone depletion may upset, perhaps irrevocably the fragile balance of the entire global ecosystem. This depletion is such a deadly threat due to the resulting increases in ultra violet radiation. In 1990, an all party committee produced a report entitled "Deadly Releases - CFC's". This report began with the following conclusion: "We, the members of the committee, have reached one overpowering conclusion - not just a consensus, but a unanimous opinion - that ozone depletion is a threat to the continuation of life on Earth." Unfortunately, since the time of that release, things have only become worse. Currently, the ozone layer has been depleted between 10% - 30%. The resulting ultra violet radiation increases are the real threat. Scientist have determined that for every 1% decrease in stratospheric ozone, there is a corresponding 2% increase in ultra violet radiation. WHAT IS THE PROBLEM? Ozone is a compound of three oxygen atoms, unlike oxygen in the air we breathe that contains two oxygen atoms. In the stratosphere, the atmospheric layer between six and 30 miles above Earth's surface, ozone forms a layer that shields the Earth against ultraviolet radiation from the sun. (It is important to note that whereas ozone in the stratosphere is absolutely necessary to protect the Earth, in the lower atmosphere - where it is a by-product of fossil fuel burning - ozone is a harmful air pollutant.) If compressed at sea level, the ozone layer would be no more than 3mm thick. Recently, scientists have recorded a decline in stratospheric ozone levels from 10% to 30%. It is predicted that as the ozone layer thins, there will be an increased incidence of skin cancer and eye cataracts, as well as extensive crop damage, destruction of marine life and immune suppression. Ozone depletion has been linked primarily to the use of chlorofluorocarbons (CFCs) and halons. CFCs are used as cooling agents in refrigerators and air conditioners, as blowing agents for foam insulation, as cleaning agents in electronics manufacturing, and (in some countries) as propellants for aerosol sprays. Halons are used in fire suppression systems. Before the link was made between CFCs and ozone depletion, CFCs were considered an ideal chemical because they are nonflammable and nontoxic. But because of their stable nature, CFCs remain intact in the atmosphere for many years, eventually working their way up to the stratosphere. Once in the stratosphere, ultraviolet light breaks apart the CFC compound, freeing the chlorine atom to catalyze a reaction with ozone molecules, converting them to oxygen molecules. Oxygen molecules do not provide the same protection from ultraviolet radiation. One CFC molecule may be responsible for the destruction of as many as 100,000 ozone molecules. Moreover, the lifespan of a single CFC molecule can be over 100 years. In 1985, a hole the size of the continental United States was discovered in the ozone layer over Antarctica. Each subsequent spring, decreases in ozone of up to 40 percent have been recorded over Antarctica. NASA, and other scientific bodies have recently reported ozone decreases of up to fifteen percent over densely populated areas of North America and Europe. In addition, NASA has predicted that future ozone depletion will reach 30%-40% in the Northern Atmosphere. According to the United States Environmental Protection Agency, there will be an increase of 20,000 skin cancer cases for every one percent decrease in ozone. WHAT CAN BE DONE TO SLOW OZONE DEPLETION? In 1987, an international convention was held in Montreal to discuss some possible solutions to ozone depletion. This meeting resulted in the Montreal Protocol, which calls for a 1989 freeze on production of CFCs at 1986 levels and a 50 percent reduction by 1998. More recently, several industrial countries, including the United States, have called for a total phase-out by the year 2000. Dupont, the world's largest producer of CFCs, has announced that it plans to phase out future production of CFCs by the end of the century. Canada has taken the initiative to phase out CFC's and Halons before the Montreal Protocol deadlines. Canada's phase out schedule is as follows: CFC's 75 % by 1/1/94 100% by 1/1/96 Halons 100% by 1/1/94 Methyl Chloroform 50 % by 1/1/94 85 % by 1/1/95 100% by 1/1/96 Carbon Tetrachloride 100% by 1/1/95 Consumers can slow the rate of ozone depletion through sensitive purchasing and use of products and appliances. Some suggestions are: * Immediately repair any leaks in your refrigerator, and ask that the CFCs be recycled when the refrigerator is serviced or before it is scrapped. * When purchasing a car, consider one without air conditioning. A light coloured model with a white interior can help keep temperatures down. * If you already own a car with air conditioning, have it professionally checked periodically for leaks and make sure the CFCs are recycled anytime the air conditioner is serviced and before the car is scrapped. The proper recycling equipment for professional air conditioner servicing businesses is now available nationally. * Consider alternatives to air conditioning in your home. Some suggestions: -Install an effective fan-cooling system. -Plant trees on the southern side of your house to provide shade. (Trees that lose their leaves in the winter will allow sunlight to warm your home in cooler months). -Apply a coat of reflective seal on your roof to keep out heat. (Any light coloured material will do the job.) * Consider alternatives to rigid foam insulation that contains CFCs. * Purchase a hand-held fire extinguisher that is halon-free. * Encourage state and local elected officials to pass laws requiring CFC recycling from air conditioning and refrigeration units. Check all products before purchase to avoid ozone damaging chemicals. These include CFC-11, CFC-12, CFC-113, CFC-114, CFC-115, Halon-1211, Halon-1301, Halon-2402, methyl chloroform and carbon tetrachloride. For more information on the effects of Ultra Violet radiation please refer to the Ultra Violet Information file in the Ozone Depletion menu. Please keep in mind that sun screens have never been proven to protect against cancer or immune suppression....For more information about sun screens please refer to the "Sun screen Effectiveness" file in the ozone depletion menu. Any comments, questions or concerns can be dealt with in the discussion section. Please be encouraged to ask any questions, or give any comments.