1. Objective: Section 18-8 to 18-9  Describe stratospheric ozone depletion and solutions to protect the ozone layer.

2. Ozone Schmozone  What is ozone?  Do I really need to care?  What is ozone?  Do I really need to care?

3. Ozone Formation in the Stratosphere Importance  Absorbs UV  Terrestrial life  Absorbs UV  Terrestrial life

4. Ozone Depletion in the Stratosphere Fig. 18-26 p. 473 Depletion  O 3 + CFCs → O 2 + CFCs + O

5. CFCs destroying ozone animation.

6. Ozone Depleting Chemicals  Chlorofluorocarbons (CFCs)  Halons  Methyl bromide  Carbon tetrachloride  Methyl chloroform  Hydrogen chloride

7. Seasonal Thinning at the Poles  Ozone thinning (hole)  Polar vortex Fig. 18-30 p. 475

8. Reasons for Concern  Increased incidence and severity of sunburn  Increase in eye cataracts  Increased incidence of skin cancer  Immune system suppression  Increase in acid deposition  Lower crop yields and decline in productivity

9. Solutions: Protecting the Ozone Layer  CFC substitutes  Technofixes  Montreal Protocol Fig. 18-33 p. 479

10. Solutions: Protecting Yourself  Common sense

11. Generalization  What chemicals play a major role in ozone thinning?  Summarize the destruction of stratospheric ozone.  What is the best solution for preventing ozone thinning?  What chemicals play a major role in ozone thinning?  Summarize the destruction of stratospheric ozone.  What is the best solution for preventing ozone thinning?

12. Objective: Section 18-8 to 18-9  Describe stratospheric ozone depletion and solutions to protect the ozone layer.