Carbon Dioxide and the Greenhouse Effect

Ordinary air contains a variable amount of water vapor, but its composition on a dry basis by volume is 78.08% N2, 20.95% O2, 0.934% Ar, and, presently, only 0.036% (360 parts per million, ppm) CO2, plus minor amounts of Ne, He, CH4, Kr, H2, N2O, and Xe. Nevertheless, carbon dioxide is believed to exert a major influence on climate through the greenhouse effect sunlight penetrates the atmosphere, is mostly absorbed by the Earth, and is reemitted as infrared radiation, but an important frac- 

5 °C by the year 2100 have been predicted on the basis of revisions of various models (earlier versions predicted a 1.5 to 4.5 °C increase by the mid-twentyfirst century). At the time of writing (1996), an international consensus is emerging to the effect that global warming is indeed occurring, and that it is probably correlated with the atmospheric CO2 concentration. 

The United Nations Panel on Climate Change made several recommendations to limit CO2 emissions, including the following  

The reality is, however, that it will be politically difficult or impossible to stabilize CO2 emissions at 1990 levels, let alone bring about a significant reduction. Rubin et discuss some realistic mitigation options. 

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RGAM1ZATI0N A major organizational change from the third to fourth edition has been the conversion and expansion of the topics previously found in Chapter 16 (Air The Precious Canopy) into three separate chapters. This material, now Chapter 4 (The Air We Breathe), Chapter 6 (Carbon Dioxide and the Greenhouse Effect), and Chapter 7 (Chlorofluorocarbons and the Ozone Layer), has been moved to a more prominent place early in the text. The very limited treatment of acid rain in Chapter 16 of the third edition has... 

Carbon. Most of the Earth s supply of carbon is stored in carbonate rocks in the Hthosphere. Normally the circulation rate for Hthospheric carbon is slow compared with that of carbon between the atmosphere and biosphere. The carbon cycle has received much attention in recent years as a result of research into the possible relation between increased atmospheric carbon dioxide concentration, most of which is produced by combustion of fossil fuel, and the "greenhouse effect," or global warming. Extensive research has been done on the rate at which carbon dioxide might be converted to cellulose and other photosyntheticaHy produced organic compounds by various forms of natural and cultivated plants. Estimates also have been made of the rate at which carbon dioxide is released to soil under optimum conditions by various kinds of plant cover, such as temperature-zone deciduous forests, cultivated farm crops, prairie grassland, and desert vegetation. 

After some dramatic last-minute bargaining, a draft document was accepted by the conference and signed by all who attended. The hnal document called for reductions in carbon dioxide and other greenhouse gas emissions ranging from 6 percent below 1990 levels for Japan to 8 percent below those levels for members of the European Union. (The United States was assigned a 7 percent reduction.) The treaty was scheduled to go into effect when 55 nations accounting for at least 55 percent of all global carbon dioxide emissions had ratified the treaty. 

Many scientists have attributed global warming and the greenhouse effect to increases in carbon dioxide in the atmosphere. Because all combustion-fired glass melters are fired with carbon-based fuels such as natural gas or oil, one of the products of combustion is C02. Obviously, the more one saves fuel, the more one reduces C02 emissions. As discussed previously, oxygen-based combustion can reduce fuel consumption by 5 to 45%. This directly relates to a corresponding C02 reduction of 5 to 45%. 

Carbon Dioxide Gas and the Greenhouse Effect 213 Stratospheric Ozone (An Absorber of Ultraviolet Rays) Water (A Special Substance for Planet Earth) 465 Acid Rain 700 Limestone Caves 748 The Chernobyl Nuclear Accident 892... 

Burning of any hydrocarbon (fossil fuel) or, for that matter, any organic material converts its carbon content to carbon dioxide and its hydrogen to water. Because power plants and other industries emit large amounts of carbon dioxide, they contribute to the so-called greenhouse warming effect on our planet, which causes significant en-... 

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