Greenhouse Gases
The most damaging greenhouse gas, carbon dioxide, is released into the atmosphere from the burning of fossil fuels. Factory emissions contribute greatly to the release of carbon dioxide into the atmosphere, and it is estimated that industry and electrical generating factories contribute slightly more than 50 percent of greenhouse gases. Another harmful gas from the use of fossil fuels is sulfur dioxide, a key ingredient in the formation of acid rain. Sulfur dioxide, however, is a double-edged sword. While it contributes greatly to acid rain, its presence in the atmosphere helps cool the air to counteract the heating caused by carbon dioxide.