1. 16.2 Air Quality KEY CONCEPT Fossil fuel emissions affect the biosphere.

2. 16.2 Air Quality Pollutants accumulate in the air. Pollution is any undesirable factor added to the air, water, or soil. Smog is one type of air pollution. OZONE LAYER HOLE CAUSED BY USE OF CFC’s = AEROSOLS, ETC….BANNED IN 1995

3. 16.2 Air Quality Smog can be harmful to human health. Acid rain is caused by fossil fuel emissions. –produced when pollutants in the water cycle cause rain pH to drop –can lower the pH of a lake or stream –can harm trees

4. 16.2 Air Quality Air pollution is changing Earth’s biosphere. The levels of atmospheric carbon dioxide rise and fall over time. High levels of carbon dioxide are typical of Earth’s warmer periods.

5. 16.2 Air Quality The greenhouse effect occurs when the gases act as a blanket (as an insulator) that slows the release of energy and helps to keep the Earth at a temperature that can support life = GOOD! methane ( CH 4 ) water (H 2 O ) carbon dioxide (CO 2 ) 1.Light emitted from the sun comes to Earth 2.Energy is absorbed by the earth and radiated as heat 3.Green house gases in the atmosphere absorb wavelengths of light 4.Molecules re-release infrared radiation, which is re-absorbed or lost to outer space. --Water, Carbon dioxide and methane are the 3 most common greenhouse gases.

6. 16.2 Air Quality Global warming refers to the trend of increasing global temperatures. North Pole