1. Human Impact on the Environment Chapter 43

2. Pollution  Pollutants are substances that ecosystems have no natural experience with and cannot adapt to.

3. Air Pollution  Smog – a gray or brown haze found in major cities.  Develops from the burning of coal and fossil fuels for manufacturing, heating, and making electric power.

4. Acid Deposition  Factories emit sulfur oxides, and the burning of fossil fuels emit nitrogen oxides.  Both dissolve in atmospheric water and fall to the earth as acid rain.

5. Ozone Thinning  The ozone layer is essential for preventing damaging UV radiation from reaching the earth.

6.  CFCs (chlorofluorocarbons) are major problems in ozone depletion.  CFCS are found in refrigerators and air conditioners as coolant, in plastic foams and other solvents.

7. Deforestation  Removal of all trees from large tracts of land for agriculture, logging or grazing.  The forests are important for regulating water flow.

8.  As the forests are cut down, the water is uncontrolled, causing soil erosion, flooding, and the accumulation of sediment that clog rivers, lakes, or reservoirs

9. Desertification  The conversion of large tracts of natural grasslands to more desert like conditions.  About 200,000 square kilometers are being converted annually. Overgrazing of livestock is the main cause.

10. Water Crisis  The Earth has a great supply of water, but most of it is too salty.  Desalinization is not an answer, due to the extreme cost and resulting mountains of salt.

11. Water Pollution  Increases the problem of water shortage. Inputs of pollution have made much water undrinkable.  Water treatment is only used on 70% of water, the rest is put back into waterways untreated.

12. Solar-Hydrogen Energy  Sunlight can be trapped in photovoltaic cells and produce an electric current that splits water into oxygen and hydrogen  Considerably cheaper than using fossil fuels.

13. Fusion  Condensing atomic nuclei into fusing and releasing power.  Researchers are able to mimic this and release some energy.

14.  Currently, not much power can be released this way, but work is being done to increase the amount of energy released.