Chlorofluorocarbon greenhouse effect

Ramanathan V. Greenhouse effect due to chlorofluorocarbons Climatic implications. Science. 1975 190 50-52. 

Chlorofluorocarbon Alternatives. There still is no completely satisfactory propellant for use in the aerosol method of foam production. Chloroflu-orocarbons, still widely used, are harmful 10 atmospheric ozone and low molecular weight hydrocarbons, now popular, e g., in producing shaving cream, are explosive and promote the greenhouse effect. See also Fluorine. 

Infrared (IR) active gases, like water vapor (H20), carbon dioxide (C02), ozone (03), methane (CH4), nitrous oxide (N20), chlorofluorocarbons CFC-11 (CC13F) and CFC-12 (CC12F2) naturally and anthropogenically present in the Earth s atmosphere, absorb thermal IR radiation emitted by the Earth s surface and atmosphere. This phenomenon is known as the atmospheric greenhouse effect , and the IR active... 

Ramanathan V., Greenhouse effect due to chlorofluorocarbons climatic implications. Sdence , 190, 50-52 (1975). 

Nitrous oxide, N2O, is commonly used as a mild dental anesthetic and propellant for aerosols on atmospheric decomposition, it yields its innocuous parent gases and is therefore an environmentally acceptable substitute for chlorofluorocarbons. On the other hand, N2O contributes to the greenhouse effect and is increasing in the atmosphere. Nitric oxide, NO, is an effective coordinating ligand its function in this context is discussed in Chapter 13. It also has many biological functions, discussed in Chapter 16. 

Pharmaceutical inhalation aerosols are widely used for treatment of diseases such as asthma and chronic bronchitis. There are three basic types of aerosol products the propellant-driven metered-dose inhalers, the dry powder inhalers, and the nebulizers. Because of the ozone-depleting and greenhouse effects of the chlorofluorocarbon (CFG) propellants, interest in the dry powder aerosols has risen in recent years. 

CFC s or chlorofluorocarbons are chemicals that cause ozone depletion in the stratosphere as well as the "Greenhouse Effect". They have been typically employed as blowing agent in foams. Since the initial proclamation, the mandate has been revised several times to accelerate the CFC phaseout schedule, with the latest revision resulting from the Copenhagen agreement in November 1992 where 87 nations resolved to move up total CFC phaseout by four years in January 1996. The recent Copenhagen revision induced major CFC manufacturers to accelerate their phaseout time table. DuPont announced recently that it plans to stop CFC production by 1994, almost 2 years ahead of plan. 

Direct electroreduction methods are typically used for dechlorination of chlorinated pollutants in waters. The easy removal of Cl from chlorinated organics allows conversion of chlorofluorocarbons (CFCs) into hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs), and even fluorocarbons (FCs). ECFCs are much less destructive to the atmospheric ozone than CFCs, but HFCs and FCs are harmless to atmospheric ozone, although they may contribute to the greenhouse effect. 

Hansen, J., A. Lacis and M. Prather (1989). Greenhouse effect of chlorofluorocarbons and other trace gases. /. Ceophys. Res. 94, 16,417-16,421. 

Other gases, such as chlorofluorocarbons (CFCs), also exhibit greenhouse effects but are controlled by the Montreal Protocol. As to the scientific and ethical dimensions of the effect of greenhouse gases, see Prue Taylor, An Ecological Approach to International Law Responding to Climate Change, 1997, at 9 et seq. 

Although CO2 receives most of the attention, other gases contribute to the greenhouse effect, including methane, CH4, hydrofluorocarbons (MFCs), and chlorofluorocarbons (CFCs). 

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