Smog is a general term that describes a variety of air pollutants. Vehicles and other internal combustion engines that burn fossil fuels cause about 70% of local air pollution. Motorists in the L.A. basin drive more than 318 million motor miles every day!

Local smog has global impacts. The earth's atmosphere now contains about 30% more carbon dioxide (CO2) than it did 100 years ago. This interference with the carbon cycle has been called the greenhouse effect; CO2 and other gases trap heat and contribute to global warming. Scientists have discovered that the five warmest years since the fifteenth century were all in the 1990's. Additionally, warmer temperatures alter weather patterns. Higher temperatures increase evaporation. Since water that goes up, must come down, drought and flooding may result. Also, the rise of temperatures contributes to polar icecap meltdown, resulting in the rise of sea levels.

A second concern is the reduction of the protective ozone layer, which shields us from harmful solar radiation that causes skin cancer. Southern California is responsible for over one-twentieth of the world's ozone-depleting chemicals, mostly due to methylchloride from industrial processes and from air conditioning systems that leak CFC's.

Many techniques previously cited for energy conservation also reduce air pollution. In addition:

• Purchase fuel efficient, low emission vehicles. Check the Air Quality Management District's Guide to Cleaner Cars.
• Do you have a smoking vehicle? Keep cars in good running condition to reduce air pollution and leaks. Use automotive products that are least toxic and free of CFC's. Don't top off your gas tank.
• Avoid using solvents and lighter fluids, unless you can find fluids that meet the Air Quality Management District's guidelines. In spite of the ban on CFC's, many aerosol sprays still contribute to air pollution and poor indoor air quality. Finish using the toxic substances that you already have, then purchase eco-friendly products.