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CPES Air Pollution – 2010

CPES Air Pollution – 2010. The Atmosphere Pollutants Sources, effects, solutions Acid Deposition. The Atmosphere. Atmosphere at sea level Nitrogen 78% Oxygen 21% Argon 00.93% CO2 .0355 % He 00.00005 % Methane 00.00017 %. Layers of Atmosphere.

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CPES Air Pollution – 2010

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  1. CPES Air Pollution – 2010 The Atmosphere Pollutants Sources, effects, solutions Acid Deposition

  2. The Atmosphere • Atmosphere at sea level • Nitrogen 78% • Oxygen 21% • Argon 00.93% • CO2 .0355 % • He 00.00005 % • Methane 00.00017 %

  3. Layers of Atmosphere • Troposphere first layer that the atmosphere, in contact with the Earth, • warmest. • weather systems. • average altitude about 11 km (36,000 feet = about 7 miles up). • The stratosphere • is a 15 km, 50 000 feet layer • 7 to 18 miles up • temperature increases gradually to 0° C or even as much as 10° C. • ozone layer here • Mesosphere • rarity of ozone • minimum temperature of about -80° C, • meteorites burn up • Thermosphere • Air molecules are rare in this layer, • temperatures can theoretically rise to enormous levels

  4. What is Air Pollution? • How to define pollution? • Amount of any substance that is in an amount that is harmful • Natural vs. Human-made • Concentrations

  5. Processes that Pollute (118) • Vaporization • Volatile substances • Fugitive Emissions • Gasoline & other low molecular weight organic chemicals • Combustion – burning • Burn hydrocarbons • Many hydrocarbons contain other substances • Eg coal and diesel fuel – result in air pollution – eg. sulfur • Incomplete – unburned particles (particulates) • Visible smoke • Cleanest burning – only CO2 and H2O • Activities that create dust, etc.

  6. Progress in Air Pollution • Air in U.S. now cleaner than 1970 • But, urban pollution still bad • Mexico city • Very bad  - major health risk • Mostly cars • Beijing • Coal for heating homes • Dramatic increase in cars • Los Angeles • Number one in U.S. – ozone, carbon monoxide and particulates • Cars • Climate and mountains – create and trap pollution

  7. Clean Air Legislation • Clean Air Act of 1970 • Criteria Pollutants • National Ambient Air Quality Standards: primary and secondary (NAAQS) • Air Pollutant Standards Index • EPA established 1970 • Amendments – 1990 • Focus on reducing nitrogen oxides, sulfur oxides, ozone • Emission trading introduced for sulfur • Regulate PM 2.5

  8. Environmental Protection Agency • EPA - 1970 • Establishes regulations – emission standards • Financial and tech assistance • Research • Collecting and analyzing data • Usurp regulatory and punitive responsibilities if states neglect – in PA DEP responsible

  9. U.S. Air Quality • Much improvement in 3 decades • NO2 has increased • 80% U.S. meets NAAQS goals • Exceed National Ambient Qir Quality Standards – called nonattainment areas • Example – in September, 2002 – 124 areas in which 1476 million people lived • Major problems: urban areas

  10. Criteria Pollutants NAAQS – for criteria pollutants • Sulfur dioxide • Carbon monoxide • Ozone (ground level) • Nitrogen dioxide • Lead • Particulates (now regulates only PM 2.5) • EPA Standards for above

  11. Primary vs. Secondary • Primary- as an emission • Secondary – formed in atmosphere • Primary • Carbon monoxide, sulfur dioxide, lead, VOCs • Secondary • Ozone • Can be either • Nitrogen dioxide and PM10

  12. Form of Pollutants • Particulates and lead – particulate pollutants • All others gaseous

  13. Nitrogen Oxides • Formed in process of high temp burning • Mostly vehicles and electric power plants • So what are the problems? • Key component of photochemical smog • Eutrophication • Acid deposition • Irritant • Gives smog reddish brown color

  14. Carbon Oxides • Carbon monoxide-CO2 • incomplete combustion • Irritant, and in high quantities, toxic • Produces photochemical smog • Carbon dioxide - CO • Complete combustion • Not a criteria pollutant • Thus, not regulated • Global climate change • Complete combustion- always results from burning

  15. Particulate matter • Unburned particles, dust, and other suspended particles • Most visible of all pollutants – this is smoke • Size is important • PM10 – coarse, less than 10 micrometers diameter • PM2.5 - less than 2.5 micrometers diameter • Problems • Some carcinogenic • Irritants in lungs • Lung diseases

  16. Ultra Fine Particles Fine Particles Large Particles Sea salt nuclei Fly ash Carbon black Pollens Paint pigments Tobacco smoke Cement dust Milled flour Combustion nuclei Coal dust Oil smoke Metallurgical dust and fumes Photochemical smog Insecticide dusts 0.001 0.01 2.5 10.0 100.0 Average particle diameter (micrometers or microns)

  17. Sulfur Dioxide and other oxides • About 2/3 is human caused • Colorless gas with strong odor • Fuels – oil and coal – contain sulfur • Key sources – • 70% sulfur making electricity • Metal smelting, steel, other industrial • Small % diesel fuel, fuel oil • What problems do SOx cause? • Acid deposition • Second to cancer in health effects • Lung and eye irritant

  18. Lead and Other Metals • Fuel combustion, ore smelting • No longer in gasoline – 94% decrease in air • Problems • Lead is neurotoxin • Indoor exposure • 20% inner city children • Learning difficulties and mental retardation • Mercury - coal burning • Arsenic, cadmium, nickel, halogens • These metals bioaccumulate and biomagnify

  19. VOCs • Organic compounds as a gas • Natural production • Plants produce many • Many synthetic organics-benzene, toluene, trichloroethylene • 56,000,000,000 lbs per year • Mostly hydrocarbons from unburned fuels • Key ingredient of photochemical smog

  20. Photochemical Smog Formation Require: Nitrogen Oxides Sunlight VOCs Results: Ozone PANS Other oxidants

  21. Nasty Stuff in Photochemical Smog • oxidants including ozone, • peroxyacetyl nitrate (PAN), • nitrogen dioxide and peroxide • reduction materials such as formaldehyde and acrolein

  22. Health Effects of P-C Smog • As for the effects on health, oxidants cause acute symptoms • stimulation of the eye (smarting eye, watery eye) • membrane irritation in the nose, throat and respiratory airway (sore throat, a feeling of having a burr in the throat and stuffy sinuses) • It is known that oxidant induces asthmatic fits. • When a photochemical smog alarm is officially announced, people are advised not to do intense exercise outdoors as much as possible and do indoor activities instead. Also, those who have weak constitution or invalids are advised to remain at rest even indoors. (EPA)

  23. OZONE • Ozone is the prime ingredient of smog in our cities and other areas of the country • At ground-level it is the prime ingredient of smog.

  24. Ozone Effects When inhaled, even at very low levels, ozone can: • cause acute respiratory problems • aggravate asthma • cause significant temporary decreases in lung capacity of 15 to over 20 percent in some healthy adults

  25. Ozone Effects • cause inflammation of lung tissue • lead to hospital admissions and emergency room visits [10 to 20 percent of all summertime respiratory-related hospital visits in the northeastern U.S. are associated with ozone pollution] • impair the body's immune system defenses, making people more susceptible to respiratory illnesses, including bronchitis and pneumonia.

  26. Children are most at risk from exposure to ozone • Children breathe even more air per pound of body weight than adults. • children's respiratory systems are still developing- more susceptible • Ground-level ozone is a summertime problem. • Asthma is a growing threat to children and adults. • Fourteen Americans die every day from asthma, a rate 3X than 20 years ago. • African-Americans die at a rate six times that of Caucasians.

  27. Ozone - Effects on Adults • Moderately exercising healthy adults can experience 15 to over 20 percent reductions in lung function from exposure to low levels of ozone over several hours. • Damage to lung tissue may be caused by repeated exposures to ozone -- something like repeated sunburns of the lungs • Results of animal studies - repeated exposure to high levels of ozone can produce permanent lung damage • Most at risk to ozone - people who are outdoors and moderately exercising during the summer months.

  28. Temperature Inversion • Cold air enters from outside an area, it may flow along the surface of the ground, below the warmer air. • If the difference in the density and temperature of the two air parcels is sufficient they will form two distinct layers, with the cold air forming the lower layer and the warmer air becoming the upper layer.

  29. Descending warm air mass Sea breeze Increasing altitude Decreasing temperature Inversion layer Mountain range

  30. Acid Deposition • Why not just say acid rain? • What is the normal pH of rain? • Effects • Aquatic ecosystems • Forest Damage • Buildings and monuments • Reduction efforts

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

  32. Figure 17-11Page 429

  33. Aquatic Effects of Acid Precipitation • Some Statistics • Sweden: 18000 lakes • Adirondacks: 1/2 high altitude lakes • Ontario and Quebec: 48,000; over 1 million sensitive • Eggs and fry: fish and amphibians • Food chain • Degree of sensitivity • Leaching: Aluminum & other metals

  34. Figure 17-14Page 431 Water boatman Whirligig Yellow perch Lake trout Brown trout Salamander (embryonic) Mayfly Smallmouth bass Mussel 6.5 6.0 5.5 5.0 4.5 4.0 3.5 pH

  35. Prevention Cleanup Reduce air pollution by improving energy efficiency Add lime to neutralize acidified lakes Add phosphate fertilizer to neutralize acidified lakes Reduce coal use Increase natural gas use Increase use of renewable resources Burn low-sulfur coal Remove SO2 particulates, and NOx from smokestack gases Remove Nox from motor vehicular exhaust Tax emissions of SO2

  36. Forest Damage • Vermont: 50% decline in some forests • Europe: by 1985 about half of forests showed damage • High altitude forests: acid fog • Mechanisms-hard to determine • toxic metals • insect pests and disease • Damage to mutualistic fungi

  37. Effects of Air Pollution on Human Health • Stats • U.S. most polluted 15% higher early death rate as contrasted to clean areas • Can mean 5-10 lower life expectancy • Young, old, other respiratory problems, very active, super-sensitive • Chronic: bronchitis and emphysema • 250,000 in U.S./ 50,000 deaths • Smoking (3M per year worldwide)

  38. “Dilution as a Solution to Pollution” • Early attempts to deal with pollution • Moving to “remote” locations • Tall Stacks – improved local air quality, but not acceptable method to reduce levels on regional or country-wide basis • Acid precipitation quick end to this thinking

  39. Pollution Prevention • Historically: pollution controls –Setting and trying to enforce emission levels • Innovative approaches – tradable pollution permits • Marked-based incentives • make it profitable to reduce pollution

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