HTML _ IB97003 - Stratospheric Ozone Depletion: Implementation Issues
12-Jul-2000; Larry Parker, David Gushee; 10 p.

Abstract: For two decades, scientists have been warning that chlorofluorocarbons (CFCs) and halons (bromine-containing fluorocarbons) may deplete the stratospheric ozone shield that screens out some of the Sun's harmful ultraviolet rays and thus regulates the amounts which reach the Earth's surface. CFCs have been used as refrigerants, solvents, foam blowing agents, and outside the United States, as aerosol propellants; Halons are used primarily as firefighting agents. Increased radiation could result in an increase in skin cancers, suppression of the human immune system, and decreased productivity of terrestrial and aquatic organisms, including some commercially important crops. In September 1987, 47 countries (including the United States) agreed to the Montreal Protocol on Substances that Deplete the Ozone Layer, which first required controls on the world's consumption of ozone depleting substances. Over 160 countries have signed on to the Protocol, whose phasedown schedule for developed countries was accelerated twice and completely phased out Halon production at the end of 1994 and CFC production at the end of 1995. The Protocol's coverage has also been extended to include hydrochlorofluorocarbons and other chlorine- and bromine-containing substances such as some solvents and methyl bromide, a widely used soil fumigant. At their meeting in Vienna (December 1995), the Parties agreed to phase down the use of HCFCs in developing countries and to phase out production of methyl bromide in developed countries by 2010, to cap its production in developing countries in 2002. In 1997, the methyl bromide deadline for developed countries was advanced to 2005, and a developing country deadline was set at 2015. The 105th Congress enacted an amendment in October 1998 to adjust phaseout of methyl bromide to 2005. About one-third of the demand for the primary ozone-depleting substances has been eliminated through conservation. Another third has been replaced by changes to ozone layer-friendly technologies. The remaining third, largely in air conditioning, refrigeration, and rigid foam blowing, is turning to substitute substances such as HCFCs (which have 1 to 10% of the ozone-depleting potential of CFCs and are thus also on a schedule to be phased out by 2030), HFCs (some of which have significant global warming potentials), and light hydrocarbons (which are flammable and tend to be less energy-efficient). Meeting demand continues to be the primary domestic implementation issues, particularly demand for CFC-12 (used in automobile air conditioners). Higher prices for CFC-12 have made alternatives more attractive and may encourage further development. However, currently, there are no ¨drop in¨ substitutes for CFC-12. This situation has encouraged smuggling of CFC-12 into the United States and calls for more aggressive enforcement. In August 1999, the U.N. Environment Program announced an international agreement requiring countries to establish licensing systems for trading ozone-depleting chemicals that entered into force November 10th. [read report]

Topics: Stratospheric Ozone

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