1. Air Resources & Pollution
Environmental Science

2. Clean Air Components

3. Air Pollution– harmful substances build up in the air to unhealthy levels (gases, solids, or liquids)
Almost all air pollution is the result of human activities!

4. Primary vs. Secondary Air Pollutants
Primary Pollutants
Secondary Pollutants
Put directly into the air from a human activity
Car exhaust
Smoke stacks
Incinerators
Fireplaces
Come from the reaction of a primary pollutant with another pollutant or an environmental factor
Ground-level ozone
Smog
Acid rain

5. Types of Primary Air Pollutants
Source
Effects
Carbon monoxide (CO)
Cars, trucks, buses, some industrial processes
Interferes with oxygen absorption, can cause death
Nitrogen Oxides
Burning fossil fuels, power plants, some industry
Respiratory problems, brownish haze, acid precipitation
Sulfur dioxide
Mostly burning fossil fuels
Acid precipitation, respiratory problems, harm plants
Volatile Organic Compounds (VOCs)
Burning fuels, gasoline & oil spills
Smog, health problems harm plants
Particulates
construction, agriculture, fires, vehicles, industrial processes
Respiratory problems, reduce visibility, corrode metals, erode stone & concrete

6. Vehicle Exhaust
Passenger vehicles usually account for around 90% of all vehicle exhaust.
History of cleaning up auto exhaust in the U.S.:
Clean Air Act of 1970 gave EPA authority to regulate auto emissions
reducing/eliminating lead in fuels
Catalytic converters– cleans pollutants from auto exhaust

7. Catalytic Converters
Pollutants from the car exhaust react with chemicals in the apparatus

8. Smokestack scrubbers

9. Temperature Inversions– a contributing factor to air pollution problems in many metropolitan areas
A shift in the natural atmosphere, where the air above is warmer than the air at the surface.
Pollutants are trapped at the surface with the cooler air.
Certain geographic features cause this, for example a city located in a valley

10. Health Effects of Air Pollution
Short Term (reversible)
Headache
Nausea
Eye, nose, throat irritation
Coughing
Chest tightness
Upper respiratory infections
Long Term (ongoing & chronic)
Emphysema
Lung cancer
Heart disease
Worsening of asthma and emphysema

11. Indoor Air Pollution– air quality inside a building is poor
Compounds found in carpets, upholstery, building materials, paints
Radon gas– comes from the ground, seeps into buildings
Asbestos—used for insulation & fire retardant, banned in the 1970s
Can cause “sick-building syndrome”

12. Noise Pollution– can affect human health and quality of life
Caused by traffic, construction, factories, home appliances (such as air conditioners), airports, lawn equipment
Health problems include hearing loss, high blood pressure, stress, loss of sleep

13. Light Pollution— inefficient lighting that is directed upward
Wastes energy
Urban areas, diminishes the view of the night sky
Billboards, signs, street lights, building exteriors

14. Acid Precipitation– has pH 3.5-5
Causes pollution in surface water—rivers, lakes, & streams
Acid shock (occurs in spring during acid-snow melt) kills aquatic organisms
Causes erosion to metal & stone/concrete
Causes acidification of soils
Completely changes soil chemistry
Causes some nutrients to wash away
Causes metals to dissolve in soils
Rain, snow, or sleet
Caused by burning fossil fuels
H20 vapor in atmosphere reacts with sulfur dioxides and nitrogen oxides to form nitric acid and sulfuric acid

15. Acid Precipitation

16. The Greenhouse Effect– a natural phenomenon caused by our atmosphere…keeps Earth warm and determines weather patterns
Greenhouse gases– methane, carbon dioxide, water vapor
Occurs in the troposphere (the first layer of our atmosphere)

17. Global Warming– an exaggeration of the greenhouse effect
Caused by excessive greenhouse gases
created by burning of fossil fuels
industrialization & vehicles

18. Ozone layer is found in the stratosphere (2nd layer of the atmosphere)
Atmospheric ozone filters UV radiation from the sun
Ozone Depletion
Depletion of the ozone layer is caused by chlorofluorocarbons (CFCs)
Freon
Aerosols
Styrofoam
Recent efforts to reduce CFCs have resulted in repaired ozone, but CFCs are still used in developing countries where they are cheap

20. There is no real relationship between global warming and ozone depletion. Ozone depletion does NOT cause global warming!!!
Ozone depletion causes more UV rays to reach Earth
increased skin cancer
increased mutations in plants
increased cataracts