1. Chapter 13 – 1, 2 Warm - Up
1. What is the pH of pure water? What is the pH of acidic water?
2. What does sulfur dioxide do to plants?
3. How can the acid precipitation kill fish?
4. What does acid rain dissolve on building and monuments?

2. Chapter 13 – 1, 2
The Ozone Shield

3. What determines climate?
Climate – long term weather conditions
Latitude
Circulation pattern
Bodies of water
Geography

4. Low Latitude Sunlight is concentrated in a smaller area Warm all year
No summer or winter

5. High Latitude Sunlight is spread out over a larger area
Lower average temperatures
Distinct seasons

6. Atmospheric Circulation
Cold air sinks
Warm air rises
Wind – difference in air temperatures

8. Atmospheric Circulation
Prevailing Winds – blow primarily in one direction
Rotation of earth deflects to right or left

9. El Nino
Periodic change of warm and cold water masses in the Pacific Ocean
Increased rainfall

10. La Nina
Water in eastern Pacific Ocean is cooler

11. Local Geography Rain shadow – Warm, moist air rises over mountains
Cooler dry air left

12. Ozone Layer Ozone layer – area in stratosphere where ozone is located
Ozone – molecule of 3 oxygen atoms

14. Stratosphere

15. Ozone
Absorbs UV light
UV light can -
Damage cells (cancer)

16. Ozone Depletion Chlorofluorocarbons CFC’s Man-made
“Frig” and air conditioner coolants
Sprays
“Fizz” in foams

18. CFC’s Earth’s surface – stable High in atmosphere – break apart
Destroy ozone

19. CFC’s
10 – 20 years to reach stratosphere

20. Ozone Hole
1985 – Study showed ozone thinned over Antarctica 50 – 98%

22. Ozone Hole Formation Polar winter
Dark
Cold -178 F
1. Polar Stratospheric Clouds – form at high altitudes in spring

24. Ozone Hole Formation 2. CFC’s are converted to chlorine
3. UV light splits chlorine atoms in two
Spring
4. Chlorine atoms destroy ozone atoms

25. Humans
Less ozone = more UV light
Damage skin
Cancer

26. Animals and Plants Kills phytoplankton Disrupt food chain
Increases CO2

28. Animals and Plants Kills amphibian eggs Interferes with photosynthesis
Laid near surface
Mutations
Interferes with photosynthesis

30. Protecting Ozone Montreal Protocol CFC replacements
Countries met to reduce or eliminate CFC’c
CFC replacements
Aerosol cans
Air conditioners
Active in stratosphere 60 – 120 years