ENVIRONMENTAL SCIENCE

1. ENVIRONMENTALSCIENCE CHAPTER 15:Part 1 Air Pollution

2. Three Big Ideas from Chap 15: #1 All countries need to step up efforts to control and prevent outdoor & indoor air pollution.

3. Three Big Ideas from Chap 15: #2. Reducing possible harmful effects of projected rapid climate change during this century requires emergency action to: cut energy waste sharply reduce greenhouse gas emissions rely more on renewable energy resources slow population growth.

4. Three Big Ideas from Chap 15: #3. We need to continue phasing out use of chemicals that have reduced ozone levels in the stratosphere and allowed more harmful UV radiation to reach earth’s surface.

5. South Asia’s Massive Brown Cloud Fig. 15-1, p. 368

6. South Asia’s Massive Brown Cloud • Changing weather patterns • 700,000 premature deaths per year • Has traveled to west coast of U.S. • Made worse by global warming

7. Atmospheric pressure (millibars) 75 65 55 45 35 25 15 5 0 200 400 600 800 1,000 120 110 100 90 80 70 60 50 40 30 20 10 0 Temperature Thermosphere Mesopause Mesosphere Altitude (kilometers) Altitude (miles) Stratopause Stratosphere Tropopause Ozone layer Troposphere Pressure (Sea Level) Pressure = 1,000 Millibars at ground level –80 –40 0 40 80 120 Temperature (°C) Fig. 15-2, p. 370

8. Earth’s Atmosphere • Troposphere = all life • 5-11 miles above earth’s surface • 75–80% earth’s air mass • 78% N2, 21% O2 • Stratosphere

9. 3 major outdoor air pollution problems are: industrial smog  burning coal photochemical smog  motor vehicle & industrial emissions acid deposition  coal burning & motor vehicle exhaust.

10. most threatening indoor air pollutants: smoke and soot from wood & coal fires (mostly in developing countries) chemicals used in building materials & products.

11. Outdoor Air Pollution • What is air pollution? • Natural & Anthropogenic • Stationary and mobile sources • Primary pollutants • Secondary pollutants

12. Types of Major Air Pollutants 1. Carbon oxides(CO, CO2) 2. Nitrogen oxides and nitric acid (NO, NO2, HNO3) 3. Sulfur dioxide and sulfuric acid (SO2, H2SO4) 4. Particulates(SPM) 5. Ozone(O3) 6. Volatile organic compounds(VOCs)

13. Primary Pollutants CO CO2 Secondary Pollutants SO2 NO NO2 SO3 Most hydrocarbons HNO3 H2SO4 Most suspended particles H2O2 O3 PANs Most NO3– and SO42– salts Sources Natural Stationary Mobile Fig. 15-3, p. 371

14. Industrial Smog • Burning coal • S impurities • Sulfur dioxide, sulfuric acid, suspended particles (soot) • Developed vs Developing countries • Air pollution control in U.S. & Europe • China, India, Ukraine

15. Photochemical Smog • Photochemical reactions • Photochemical smog • Brown-air smog • Sources • Health effects • Urban areas

17. Inversion Layer: Rogue valley Air Quality

18. Natural Factors That Reduce Air Pollution

19. Natural Factors That Increase Air Pollution

20. Acid Deposition • Sulfur dioxides and nitrogen oxides • Wet and dry deposition • Acid rain • Regional air pollution

21. Wind Transformation to sulfuric acid (H2SO4) and nitric acid (HNO3) Windborne ammonia gas and some soil particles partially neutralize acids and form dry sulfate and nitrate salts Wet acid deposition (droplets of H2SO4 and HNO3 dissolved in rain and snow) Nitric oxide (NO) Sulfur dioxide (SO2) and NO Dry acid deposition (sulfur dioxide gas and particles of sulfate and nitrate salts) Acid fog Lakes in shallow soil low in limestone become acidic Lakes in deep soil high in limestone are buffered Fig. 15-5, p. 374

22. acid deposition Potential problem areas because of sensitive soils Potential problem areas because of air pollution: emissions leading to acid deposition Current problem areas (including lakes and rivers) Fig. 15-6, p. 375

23. Harmful Effects of Acid Deposition • Structural damage • Respiratory diseases in humans • Toxic metal leaching • Kills fish and other aquatic organisms • Leaches plant nutrients from soil • Acid clouds and fog at mountaintops

25. Solutions Acid Deposition Prevention Cleanup Reduce coal use Add lime to neutralize acidified lakes Burn low-sulfur coal Increase natural gas use Add phosphate fertilizer to neutralize acidified lakes Increase use of renewable energy resources Remove SO2 particulates & NOx from smokestack gases Remove NOx from motor vehicular exhaust Tax emissions of SO2 Reduce air pollution by improving energy efficiency Fig. 15-7, p. 376

26. Indoor Air Pollution • Developing countries • Indoor cooking and heating • Smoking • Often higher concentration in buildings and cars • Most time is spent indoors or in cars • EPA  top cancer risk

27. Major Indoor Air Pollutants • Tobacco smoke • Formaldehyde • Radioactive radon-222 gas • Very small particles

28. Chloroform Source: Chlorine-treated water in hot showers Possible threat: Cancer Para-dichlorobenzene Source: Air fresheners, mothball crystals Threat: Cancer Tetrachloroethylene Source: Dry-cleaning fluid fumes on clothes Threat: Nerve disorders, damage to liver and kidneys, possible cancer Formaldehyde Source: Furniture stuffing, paneling, particleboard, foam insulation Threat: Irritation of eyes, throat, skin, and lungs; nausea; dizziness 1,1,1-Trichloroethane Source: Aerosol sprays Threat: Dizziness, irregular breathing Styrene Source: Carpets, plastic products Threat: Kidney and liver damage Nitrogen oxides Source: Unvented gas stoves and kerosene heaters, woodstoves Threat: Irritated lungs, children's colds, headaches Benzo-α-pyrene Source: Tobacco smoke, woodstoves Threat: Lung cancer Particulates Source: Pollen, pet dander, dust mites, cooking smoke particles Threat: Irritated lungs, asthma attacks, itchy eyes, runny nose, lung disease Radon-222 Source: Radioactive soil and rock surrounding foundation, water supply Threat: Lung cancer Tobacco smoke Source: Cigarettes Threat: Lung cancer, respiratory ailments, heart disease Asbestos Source: Pipe insulation, vinyl ceiling and floor tiles Threat: Lung disease, lung cancer Carbon monoxide Source: Faulty furnaces, unvented gas stoves and kerosene heaters, woodstoves Threat: Headaches, drowsiness, irregular heartbeat, death Methylene chloride Source: Paint strippers and thinners Threat: Nerve disorders, diabetes Stepped Art Fig. 15-8, p. 377

29. Why are the highest death rates in eastern half of US? <1 1–5 5–10 10–20 20–30 30+ Deaths per 100,000 adults per year Fig. 15-10, p. 378

30. U.S. Outdoor Air Pollution • Control Laws • Clean Air Acts • Air-quality standards for 6 major pollutants • Levels of these 6 pollutants have fallen dramatically btwn 1980 and 2008

33. Using the Marketplace • to Reduce Air Pollution • Emissions trading (cap and trade) program • Proponents  cheaper and more efficient • Critics  companies buy their way out • Success depends on cap being gradually lowered

34. Solutions Stationary Source Air Pollution Dispersion or Cleanup Prevention Burn low-sulfur coal Disperse emissions above thermal inversion layer with tall smokestacks Remove sulfur from coal Remove pollutants after combustion Convert coal to a liquid or gaseous fuel Shift to less polluting energy sources Tax each unit of pollution produced Fig. 15-11, p. 380

35. Solutions Motor Vehicle Air Pollution Prevention Cleanup Require emission control devices Use mass transit Walk or bike Use less polluting fuels Inspect car exhaust systems twice a year Improve fuel efficiency Get older, polluting cars off the road Give large tax write-offs or rebates for buying low- polluting, energy efficient vehicles Set strict emission standards Fig. 15-12, p. 381

36. Solutions What can you do? Indoor Air Pollution Prevention Cleanup or Dilution Clean ceiling tiles and line AC ducts to prevent release of mineral fibers Use adjustable fresh air vents for work spaces Increase intake of outside air Ban smoking or limit it to well-ventilated areas Change air more frequently Set stricter formaldehyde emissions standards for carpet, furniture, and building materials Circulate a building’s air through rooftop greenhouses Prevent radon infiltration Use efficient venting systems for wood- burning stoves Use office machines in well- ventilated areas Use exhaust hoods for stoves and appliances burning natural gas Use less polluting substitutes for harmful cleaning agents, paints, and other products Fig. 15-13, p. 381

37. Solutions Air Pollution Outdoor Indoor Improve energy efficiency to reduce fossil fuel use Reduce poverty Distribute cheap and efficient cookstoves or solar cookers to poor families in developing countries Rely more on lower-polluting natural gas Rely more on renewable energy (especially solar cells, wind, geothermal and solar-produced hydrogen) Reduce or ban indoor smoking Transfer energy efficiency, renewable energy, and pollution prevention technologies to developing countries Develop simple and cheap tests for indoor pollutants such as particulates, radon, and formaldehyde Fig. 15-15, p. 382

38. ENVIRONMENTALSCIENCE CHAPTER 15:Part 2 Climate Change, & Ozone Depletion

39. Global Warming: the Biological & Chemical Aspects

40. AVERAGE TEMPERATURE (over past 900,000 years AVERAGE TEMPERATURE (over past 130 years TEMPERATURE CHANGE (over past 22,000 years TEMPERATURE CHANGE (over past 1,000 years Glacial and interglacial periods (Global cooling and global warming)

41. What is the Greenhouse Effect?

42. What is the Greenhouse Effect?

43. Not all gases interact with & absorb I.R. radiation

44. Top 6 Greenhouse Gases: Water vapor H2O Carbon dioxide CO2 Methane CH4 Nitrous Oxide N2O Ozone O3 Chlorofluorocarbons CFC’s Trap infrared radiation (heat) to the Earth

46. What impact do atmospheric gases have on the Greenhouse effect?

47. Time gases spend in the atmosphere • Ability to re-radiate heat back to Earth Approx. time Greenhouse Gas in atmosphere H2O rapidly CH4 (methane) ~12 yrs Nitrous oxide ~120 yrs Halocarbons ~Varies: weeks to 50,000 yrs CO2 ~100 yrs

49. Natural Sources of Green House Gases Methane: rice patties, swamp gases, termites & ruminants (methanogenic microbes).

50. Other methane sources: