1. Air Pollution Chapter 20

2. The Atmosphere as a Resource Atmospheric composition: Nitrogen = 78% Oxygen = 21% Argon = 0.93% Carbon dioxide = 0.04%

3. The Atmosphere  Separation of layers by altitude and temperature  due to differences in temperature and variations in absorption of solar energy  Most of our weather in the troposphere  Greenhouse gases  Ozone layer - Stratosphere  Separation of layers by altitude and temperature  due to differences in temperature and variations in absorption of solar energy  Most of our weather in the troposphere  Greenhouse gases  Ozone layer - Stratosphere Pressure = 1,000 millibars at ground level Atmospheric pressure (millibars) 02004006008001,000 120 110 100 90 80 70 60 50 40 30 20 10 0 (SeaLevel) –80–4004080120 Temperature (˚C) Altitude (kilometers) Altitude (miles) 75 65 55 45 35 25 15 5 Thermosphere Heating via ozone Mesosphere Stratosphere Ozone “layer” Heating from the earth Troposphere Temperature Pressure Mesopause Stratopause Tropopause Fig.20.3

4. The Greenhouse Effect

5. Human Influences on Greenhouse Gas Emissions:

6. Types and Sources of Air Pollution Major Air Pollutants – chart in your textbook

7. Types and Sources of Air Pollution Primary and Secondary Air Pollutants

8. Difference b/w Primary and Secondary Pollutants Primary Pollutants – those released directly into the lower atmosphere (troposphere) and are toxic!

9. Difference b/w Primary and Secondary Pollutants Secondary Pollutants – Those formed by the combination of primary pollutants in the atmosphere i.e. Acid Rain SO 2 + water vapor = H 2 SO 4

10. Types and Sources of Air Pollution Criteria Pollutants: Major Classes of Air Pollutants (the dirty half dozen) Particulate matter Nitrogen oxides Sulfur oxides Carbon oxides Hydrocarbons Ozone Ozone damage

11. I thought that Ozone was a good thing? Stratospheric Ozone – O 3 – this layer of gas traps UV radiation = Good! Tropospheric Ozone Up high Ozone helps Down low = secondary pollutant Combines with NO x, heat, sunlight and VOCs – contributes to SMOG

12. Nitrogen Dioxide – NO 2 Atmospheric N and O 2 react at high temperatures – such as in engines! 50% of NO 2 in atmosphere from engines Other sources = utilities, industrial combustion Secondary pollutant (smog/acid rain)

13. Table 20-2 Page 438 Table 20-2 Major Outdoor Air Pollutants NITROGEN DIOXIDE (NO 2 ) Description: Reddish-brown irritating gas that gives photochemical smog its brownish color; in the atmosphere can be converted to nitric acid (HNO 3 ), a major component of acid deposition. Major human sources: Fossil fuel burning in motor vehicles (49%) and power and industrial plants (49%). Health effects: Lung irritation and damage; aggravates asthma and chronic bronchitis; increases susceptibility to respiratory infections such as the flu and common colds (especially in young children and older adults). Environmental effects: Reduces visibility; acid deposition of HNO 3 can damage trees, soils, and aquatic life in lakes. Property damage: HNO 3 can corrode metals and eat away stone on buildings, statues, and monuments; NO 2 can damage fabrics. Nitrogen Dioxide

14. Sulfur Dioxide Colorless gas, suffocating odor and lung irritant! Released through coal combustion, paper manufacturing, fossil fuel combustion. Scrubbers in power plants have helped to reduce SO 2 release. Reacts with O 2 = Acid precipitation !

15. Table 20-2 Page 438 Table 20-2 Major Outdoor Air Pollutants SULFUR DIOXIDE (SO 2 ) Description: Colorless, irritating; forms mostly from the combustion of sulfur containing fossil fuels such as coal and oil (S + O 2 SO 2 ); in the atmosphere can be converted to sulfuric acid (H 2 SO 4 ), a major component of acid deposition. Major human sources: Coal burning in power plants (88%) and industrial processes (10%). Health effects: Breathing problems for healthy people; restriction of airways in people with asthma; chronic exposure can cause a permanent condition similar to bronchitis. According to the WHO, at least 625 million people are exposed to unsafe levels of sulfur dioxide from fossil fuel burning. Environmental effects: Reduces visibility; acid deposition of H 2 SO 4 can damage trees, soils, and aquatic life in lakes. Property damage: SO 2 and H 2 SO 4 can corrode metals and eat away stone on buildings, statues, and monuments; SO 2 can damage paint, paper, and leather. Sulfur Dioxide

16. Table 20-2 Page 438 Table 20-2 Major Outdoor Air Pollutants SUSPENDED PARTICULATE MATTER (SPM) Description: Variety of particles and droplets (aerosols) small and light enough to remain suspended in atmosphere for short periods (large particles) to long periods (small particles; Figure 20-6, p. 441); cause smoke, dust, and haze. Major human sources: Burning coal in power and industrial plants (40%), burning diesel and other fuels in vehicles (17%), agriculture (plowing, burning off fields), unpaved roads, construction. Health effects: Nose and throat irritation, lung damage, and bronchitis; aggravates bronchitis and asthma; shortens life; toxic particulates (such as lead, cadmium, PCBs, and dioxins) can cause mutations, reproductive problems, cancer. Environmental effects: Reduces visibility; acid deposition of H 2 SO 4 droplets can damage trees, soils, and aquatic life in lakes. Property damage: Corrodes metal; soils and discolors buildings, clothes, fabrics, and paints. Suspended Particulate Matter

17. Table 20-2 Page 438 Table 20-2 Major Outdoor Air Pollutants LEAD Description: Solid toxic metal and its compounds, emitted into the atmosphere as particulate matter. Major human sources: Paint (old houses), smelters (metal refineries), lead manufacture, storage batteries, leaded gasoline (being phased out in developed countries). Health effects: Accumulates in the body; brain and other nervous system damage and mental retardation (especially in children); digestive and other health problems; some lead-containing chemicals cause cancer in test animals. Environmental effects: Can harm wildlife. Lead

18. Table 20-2 Page 438 Table 20-2 Major Outdoor Air Pollutants OZONE (O 3 ) Description: Highly reactive, irritating gas with an unpleasant odor that forms in the troposphere as a major component of photochemical smog (Figures 20-3 and 20-5). Major human sources: Chemical reaction with volatile organic compounds (VOCs, emitted mostly by cars and industries) and nitrogen oxides to form photochemical smog (Figure 20-5). Health effects: Breathing problems; coughing; eye, nose, and throat irritation; aggravates chronic diseases such as asthma, bronchitis, emphysema, and heart disease; reduces resistance to colds and pneumonia; may speed up lung tissue aging. Environmental effects: Ozone can damage plants and trees; smog can reduce visibility. Property damage: Damages rubber, fabrics, and paints. Ozone

19. Types and Sources of Air Pollution Primary Air Pollutants

20. Types and Sources of Air Pollution Sources of Outdoor Air Pollution

21. Types and Sources of Air Pollution Urban Air Pollution

22. Types and Sources of Air Pollution Case-in-Point: Air Pollution in Los Angeles and Mexico City Sources of smog in Los Angeles

23. Types and Sources of Air Pollution Case-in-Point: Air Pollution in Los Angeles and Mexico City Smog in Mexico City

24. Effects of Air Pollution Air Pollution and Human Health

25. Effects of Air Pollution Health Effects of Specific Air Pollutants Sulfur dioxide, nitrogen dioxide, & particulate matter – airway irritation and constriction Carbon monoxide – headache, fatigue, drowsiness, death Ozone – burning eyes, coughing, and chest discomfort

26. Controlling Air Pollution in the United States Controlling Air Pollutants Turned ON Electrostatic precipitator Turned OFF

27. Controlling Air Pollution in the United States Controlling Air Pollutants Scrubber

28. Controlling Air Pollution in the United States Clean Air Act Emissions in the US, 1970 vs. 2000

29. Controlling Air Pollution in the United States US Urban Areas with Worst Air Quality, 2002

30. Controlling Air Pollution in the United States Other Ways to Improve Air Quality Reducing the sulfur content in gasoline Require federal emissions standards to apply to ALL passenger vehicles Require emission testing for ALL vehicles

31. Air Pollution Around the World Many nations do not have most current pollution scrubbing technologies Air pollution in China

32. Air Pollution Around the World http://ca.pbslearningmedia.org/resource/ean08.sci.ess.earthsys.arctichaze/arctic-haze http://www.youtube.com/watch?v=Ye45DGkqUkE

33. Solutions? Plants! http://www.youtube.com/watch?v=gmn7tjSNyAA

34. Indoor Air Pollution

35. Indoor Air Pollution and the Asthma Epidemic # of asthma sufferers has doubled since 1970 Exactly why is unknown, but thought to be linked to increased indoor air pollution

36. Indoor Air Pollution Radon

37. 20.3 Photochemical and Industrial Smog

38. Smog Photochemical: “brown air smog” Caused by UV reacting with chemicals (NOx, VOCs in the atmosphere) Found in modern cities, especially in warm, sunny areas. Industrial smog: “gray air smog” Caused by burning of fossil fuels, adds sulfur to air. Rare in developed countries now as soot is removed by filters..

39. Photochemical Smog Nitrogen oxide is an essential ingredient of photochemical smog that is produced during the high temperatures associated with combustion of vehicle’s engines. Be sure to look at sheet “Chemistry is indeed relevant to APES.”

40. Initial reaction of nitrogen dioxide with sunlight

41. Factors in smog formation Precipitation Salty sea spray Wind Reduce factory/car emissions Urban buildings Hills and mountains High temperatures “Grasshopper Effect” Decrease smogIncrease smog

42. “Grasshopper Effect” This is one reason why the dangerous chemicals Canada banned more than 20 years ago continue to turn up in the Great Lakes.

43. View “Chemistry is indeed relevant to APES.” See equation – reactants and products of photochemical smog on sheet. Hydrocarbons (including VOC’s), carbon monoxide, and nitrogen oxides from vehicle exhausts are irradiated by sunlight in the presence of oxygen gas. The resulting reactions produce a potentially dangerous mixture that include other NOx, ozone, and irritating organic compounds (VOC’s), as well as CO2 and H2O vapor

44. 20.4 Regional Outdoor Air Pollution from Acid Deposition

45. Acid Rain PlayPlay intro video

46. Chemistry and Acid Rain The pH of rainwater is normally slightly acidic, at about 5.6, due mainly to reaction of carbon dioxide with water to form carbonic acid. Refer to “Chemistry is indeed relevant to APES.”

47. Gases from natural events Volcanic eruptions, forest fires, and lightning produce sulfur dioxide, sulfur trioxide, and nitrogen dioxide. These gases can react with atmospheric water in much the same way that carbon dioxide does to produce sulfurous acid, sulfuric acid, nitric acid and nitrous acid. Refer to “Chemistry is indeed relevant to APES.”

48. Wind Transformation to sulfuric acid (H 2 SO 4 ) and nitric acid (HNO 3 ) Nitric oxide (NO) Acid fog Ocean Sulfur dioxide (SO 2 ) and NO Windborne ammonia gas and particles of cultivated soil partially neutralize acids and form dry sulfate and nitrate salts Dry acid deposition (sulfur dioxide gas and particles of sulfate and nitrate salts) Farm Lakes in deep soil high in limestone are buffered Lakes in shallow soil low in limestone become acidic Wet acid deposition (droplets of H 2 SO 4 and HNO 3 dissolved in rain and snow) Acid Rain formation

49. Wind Ocean Farm Which location does sulfuric & nitric acids transform? Y Z X

50. Wind Ocean Farm Identify the type of acid deposition at point Y Y Z Transformation to sulfuric acid (H 2 SO 4 ) and nitric acid (HNO 3 )

51. Wind Ocean Farm Identify the type of acid deposition at point Z X Z Dry acid deposition

52. Wind Ocean Farm Great Job!! X Y Wet acid deposition

53. Primary Pollutants Secondary Pollutants SourcesNatural Stationary COCO 2 SO 2 NONO 2 Most hydrocarbons Most suspended particles SO 3 HNO 3 H 2 SO 4 H2O2H2O2 O3O3 PANs MostandsaltsNO 3 – Mobile SO 4 2 – Which chemicals lower the pH of rain?

54. Primary Pollutants Secondary Pollutants SourcesNatural Stationary COCO 2 SO 2 NONO 2 Most hydrocarbons Most suspended particles SO 3 HNO 3 H 2 SO 4 H2O2H2O2 O3O3 PANs MostandsaltsNO 3 – Mobile SO 4 2 – Secondary Pollutants in RED

55. pH levels of US soil

56. Effects of Acid Rain Decrease soil pH (more acidic) Decrease pH of rivers, lakes, ponds, etc Fish kills Lung/respiratory problems Degrade metal pipes, leading to water pollution Plants become susceptible to disease, parasites, etc

57. Reduce air pollution by improving energy efficiency Reduce coal use Increase natural gas use Increase use of renewable resources Burn low-sulfur coal Remove SO 2 particulates, and No x from smokestack gases Remove No x from motor vehicular exhaust Tax emissions of SO 2 Add lime to neutralize acidified lakes Add phosphate fertilizer to neutralize acidified lakes Acid Rain Prevention and Solution Solutions Acid Deposition Prevention Cleanup

58. 20.5 Indoor Air Pollution

59. Go outside and play Indoor air is typically a greater threat People are inside up to 98% of their time Less air flow to remove pollutants Top pollutants: cigarette smoke, formaldehyde, radon, particulate matter. “Sick building” Typically newer buildings because of less air leaks. Symptoms: headache, coughing, sneezing, tiredness.

60. Formaldehyde Found in: plywood, furniture, upholstery, floor adhesives, dry cleaning chemicals. Causes: breathing problems, headache, sore throat, dizziness, eye irritation in those sensitive to low levels. Chronic exposure to higher levels can lead to cancer. Radon Naturally occurring from radioactive decay of U-238. Occurs in soils, bedrock and can get into homes through cracks. Can’t get out and builds up Can lead to lung cancer

61. Chloroform: chlorine- treated hot water; cancers Para-dichlorobenzene: air fresheners, moth balls; cancers Tetrachloroethylene: dry cleaning residue; nerve, liver, kidney problems Formaldehyde: from processed wood; eye, nose, throat, lung irritant Benzo-  -pyrene: from smoke; lung cancer Styrene: from carpet/plastic. Kidney/liver problems Radon- 222: from soils, lung disease Methylene Chloride: paint stripper, thinner; nerve, diabetes Tobacco Smoke Carbon Monoxide Asbestos: old floor tile, Pipe insulation; lung problems, cancer Nitrogen Oxides: Gas ovens, kerosene heaters, un-vented gas burning; lung irritation, headaches 1, 1, 1- Trichloroethane: aerosals; dizziness, irregular breathing

62. Solutions Indoor Air Pollution PreventionCleanup Cover ceiling tiles and lining of AC ducts to prevent release of mineral fibers Ban smoking or limit it to well- ventilated areas Set stricter formaldehyde emissions standards for carpet, furniture, and building materials Prevent radon infiltration Use office machines in well- ventilated areas Use less polluting substitutes for harmful cleaning agents, paints, and other products Use adjustable fresh air vents for work spaces Increase intake of outside air Change air more frequently Circulate building’s air through rooftop greenhouses Use exhaust hoods for stoves and appliances burning natural gas Install efficient chimneys for wood-burning stoves

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

64. VI. Pollution (25-30%) Air pollution 1.Sources-primary and secondary (20.2 & air pollution lab) 2.major air pollutants (20.2 & pollutant chart) 3.measurement units (air pollution lab & emissions trading game) 4.smog (20.3 & Demo: Smog in a jar) 5.acid deposition-causes and effects (20.4, pH/acid rain lab, video) 6.heat islands (online activity) and temperature inversions (20.3) 7.indoor air pollution (20.5 & air particulate lab) 8.remediation and reduction strategies (air pollution allowance trading article, emissions trading game) and Fig. 20-18) 9.Clean Air Act and other relevant laws (Law sheet, NAAQS)