1. Chapter 19 Air Pollution

2. Atmosphere as a Resource
Atmospheric Composition
N: 78.08%
O: 20.95%
Ar: 0.93%
CO2: 0.04%
Ecosystem services
Blocks UV radiation
Moderates the climate
Redistributes water

3. Air Pollution - Terminology
Chemicals added to the atmosphere by natural events or human activities in high enough concentrations to be harmful
Primary Air Pollutant
Harmful substance that is emitted directly into the atmosphere
Secondary Air Pollutant
Harmful substance formed in the atmosphere when a primary air pollutant reacts with substances normally found in the atmosphere or with other air pollutants

5. Major Air Pollutants

6. Air Pollutants - Particulate Matter
Thousands of solid or liquid particles suspended in air
Ex: soil particles, soot, lead, asbestos, sea salt, and sulfuric acid droplets
Dangerous
toxic/carcinogenic effects

7. Air Pollutants Continued
Nitrogen Oxides
Some are Greenhouse gases that cause difficulty breathing and leads to photochemical smog depletes ozone in stratosphere
Sulfur Oxides
Causes acid precipitation
Carbon Oxides
Ex: and CO2- Greenhouse gases
Hydrocarbons- ex: CH4- methane
Some are related to photochemical smog and greenhouse gases

8. Air Pollutants Continued-Ozone
Tropospheric Ozone-
Man- made pollutant
Secondary air pollutant
Component of photochemical smog
VS.
Stratospheric Ozone-

9. Sources of Outdoor Air Pollution
Two main sources
1. Transportation
2. Industry
Intentional forest fires is also high

10. Urban Air Pollution Smog- air pollution that reduces visibility
Photochemical Smog
formed by chemical reactions involving sunlight, nitrogen oxide, and hydrocarbons

11. Formation of Photochemical Smog

12. Sources of Smog in Los Angeles

13. Effects of Air Pollution
Greater health threat to children than adults
Air pollution can restrict lung development
Children breath more often than adults

14. Controlling Air Pollution- (particulate matter)
Scrubber
Electrostatic precipitator

15. The Clean Air Act 1970
Authorizes EPA to set limits on amount of specific air pollutants permitted
Focuses on 6 pollutants:
lead, particulate matter, sulfur dioxide, carbon monoxide, nitrogen oxides, and ozone

16. The Clean Air Act

17. Urban Air Quality

18. Other Ways to Improve Air Quality
Reduce sulfur content in gasoline
Require federal emission standards for all passenger vehicles
Require emission testing for all vehicles

19. Ozone Depletion in Stratosphere
Ozone Protects earth from UV radiation

20. Ozone Depletion in Stratosphere
Ozone thinning/hole
First identified in 1985 over Antarctica
Caused by
human-produced bromine and chlorine containing chemicals
Ex: CFCs
Hole over Antarctica requires 2 conditions:
a mass of cold air that circulates around the southern polar region forms clouds which Cl and Br stick to
Sunlight-speeds up the reaction in which Cl and Br break up ozone

21. Effects of Ozone Depletion
Higher levels of UV-radiation hitting the earth
Eye cataracts
Skin cancer (right)
Weakened immunity
May disrupt ecosystems
May damage crops and forests

22. Recovery of Ozone Layer
Montreal Protocol (1987)
Reduction of CFCs
Started using HCFCs (greenhouse gas)
Full recovery will not occur until 2050

23. Acid Deposition

24. Effects of Acid Deposition
Declining Aquatic Animal Populations
Thin-shelled eggs prevent bird reproduction
Calcium is unavailable in acidic soil
Forest decline

25. Acid Deposition and Forest Decline

26. Air Pollution Around the World
Air quality is deteriorating rapidly in developing countries
5 worst cities in world
Beijing, China; Mexico City, Mexico; Shanghai, China; Tehran, Iran; and Calcutta, India
Air pollution can travel thousands of miles

27. Indoor Air Pollution
Pollutants can be 5-100X greater than outdoors!

28. Ahhhhh Clean Car Smell
Over sixty chemicals were identified inside the interiors of the four vehicles in this study.
Ten Most Toxic Nissan Versa Chevy Aveo Scion xB Kia Rio Suzuki Forenza Kia Spectra 5 Subaru Forester Chevy Express Hyundai Accent Chevy Silverado
Ten Least Toxic Chevy Cobalt Chrysler PT Cruiser Honda Odyssey Volvo V50 Suzuki Aerio Acura RDX BMW X3 Nissan Frontier Toyota Matrix Volvo S40
volatile organic chemicals (VOC’s) in a new minivan were over 35 times the health limit the day after its delivery 28