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Human Impact on the Atmosphere Human Impact on the Atmosphere Chapters 18 and 19 Living in the Environment, 11 th Edition, Miller Advanced Placement Environmental.

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Presentation on theme: "Human Impact on the Atmosphere Human Impact on the Atmosphere Chapters 18 and 19 Living in the Environment, 11 th Edition, Miller Advanced Placement Environmental."— Presentation transcript:

1 Human Impact on the Atmosphere Human Impact on the Atmosphere Chapters 18 and 19 Living in the Environment, 11 th Edition, Miller Advanced Placement Environmental Science La Canada High School Dr. E

2 Pollution Thorpe, Gary S., M.S., (2002). Barron’s How to prepare for the AP Environmental Science Advanced Placement Exam The term “Smog” (smoke and fog) was first used in 1905 to describe sulfur dioxide emissionThe term “Smog” (smoke and fog) was first used in 1905 to describe sulfur dioxide emission In 1952, severe pollution took the lives of 5000 people in LondonIn 1952, severe pollution took the lives of 5000 people in London “It isn’t pollution that’s harming the environment. It’s the impurities in our air and water that are doing it.” Former U.S. Vice President Dan Quayle“It isn’t pollution that’s harming the environment. It’s the impurities in our air and water that are doing it.” Former U.S. Vice President Dan Quayle 97annual.html

3 The Clean Air Act Congress found: Most people now live in urban areas Growth results in air pollution Air pollution endangers living things It decided: Prevention and control at the source was appropriate Such efforts are the responsibility of states and local authorities Federal funds and leadership are essential for the development of effective programs

4 Clean Air Act Originally signed 1963 –States controlled standards 1970 – Uniform Standards by Federal Govt. –Criteria Pollutants Primary – Human health risk Secondary – Protect materials, crops, climate, visibility, personal comfort

5 Clean Air Act 1990 version –Acid rain, urban smog, toxic air pollutants, ozone depletion, marketing pollution rights, VOC’s 1997 version –Reduced ambient ozone levels –Cost $15 billion/year -> save 15,000 lives –Reduce bronchitis cases by 60,000 per year –Reduce hospital respiratory admission 9000/year

6 Clean Air Act President George W. Bush signed rules amending Clean Air Act that allowed power plants and other industries to increase pollution significantly without adopting control measures

7 WASHINGTON (AP) -- A federal appeals court on Wednesday blocked new Bush administration changes to the Clean Air Act from going into effect the next day, in a challenge from state attorneys general and cities that argued they would harm the environment and public health. Appeals court blocks Bush clean air changes Wednesday, December 24, 2003 Posted: 2:10 PM EST (1910 GMT)

8 Clean Air Act Title I - Air Pollution Prevention and Control –Part A - Air Quality and Emission Limitations –Part B - Ozone Protection (replaced by Title VI) –Part C - Prevention of Significant Deterioration of Air Quality –Part D - Plan Requirements for Nonattainment Areas Title II - Emission Standards for Moving Sources –Part A - Motor Vehicle Emission and Fuel Standards –Part B - Aircraft Emission Standards –Part C - Clean Fuel Vehicles Title III - General Title IV - Acid Deposition Control Title V - Permits Title VI - Stratospheric Ozone Protection

9 Outdoor Air Pollution

10 Primary Pollutants Secondary Pollutants Sources Natural Stationary CO CO 2 SO 2 NO NO 2 Most hydrocarbons Most suspended particles SO 3 HNO 3 H 2 SO 4 H2O2H2O2H2O2H2O2 O3O3O3O3PANs Most andsalts NO 3 – Mobile SO 4 2 –

11 Major Sources of Primary Pollutants Stationary Sources Combustion of fuels for power and heat – Power Plants Other burning such as Wood & crop burning or forest fires Industrial/ commercial processes Solvents and aerosols Mobile Sources Highway: cars, trucks, buses and motorcycles Off-highway: aircraft, boats, locomotives, farm equipment, RVs, construction machinery, and lawn mowers

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13 54 million metric tons from mobile sources in 1990

14 Human Impact on Atmosphere Burning Fossil Fuels Using Nitrogen fertilizers and burning fossil fuels Refining petroleum and burning fossil fuels Manufacturing  Adds CO 2 and O 3 to troposphere  Global Warming  Altering Climates  Produces Acid Rain  Releases NO, NO 2, N 2 O, and NH 3 into troposphere  Produces acid rain  Releases SO 2 into troposphere  Releases toxic heavy metals (Pb, Cd, and As) into troposphere air/products.html

15 Criteria Air Pollutants EPA uses six "criteria pollutants" as indicators of air quality 1.Nitrogen Dioxide: NO 2 2.Ozone: ground level O 3 3.Carbon monoxide: CO 4.Lead: Pb 5.Particulate Matter: PM 10 (PM 2.5) 6.Sulfur Dioxide: SO 2 Volatile Organic Compounds: (VOCs) EPA established for each concentrations above which adverse effects on health may occur

16 Nitrogen Dioxide (NO 2 ) Properties: reddish brown gas, formed as fuel burnt in car, strong oxidizing agent, forms Nitric acid in air Effects: acid rain, lung and heart problems, decreased visibility (yellow haze), suppresses plant growth Sources: fossil fuels combustion, power plants, forest fires, volcanoes, bacteria in soil Class: Nitrogen oxides (NO x ) EPA Standard: ppm

17 Mobile Source Emissions: Nitrogen Oxides

18 Ozone (O 3 ) Properties: colorless, unpleasant odor, major part of photochemical smog Effects: lung irritant, damages plants, rubber, fabric, eyes, 0.1 ppm can lower PSN by 50%, Sources: Created by sunlight acting on NO x and VOC, photocopiers, cars, industry, gas vapors, chemical solvents, incomplete fuel combustion products Class: photochemical oxidants

19 Ozone (O 3 ) 10,000 to 15,000 people in US admitted to hospitals each year due to ozone-related illness Children more susceptible –Airways narrower –More time spent outdoors

20 Mobile Source Emissions: Hydrocarbons – Precursors to Ozone

21 Carbon Monoxide (CO) Properties: colorless, odorless, heavier than air, % of atmosphere Effects: binds tighter to Hb than O 2, mental functions and visual acuity, even at low levels Sources: incomplete combustion of fossil fuels % from auto exhaust Class: carbon oxides (CO 2, CO) EPA Standard: 9 ppm 5.5 billion tons enter atmosphere/year

22 Mobile Source Emissions - CO

23 Lead (Pb) Properties: grayish metal Effects: accumulates in tissue; affects kidneys, liver and nervous system (children most susceptible); mental retardation; possible carcinogen; 20% of inner city kids have [high] Sources: particulates, smelters, batteries Class: toxic or heavy metals EPA Standard: 1.5 ug/m 3 2 million tons enter atmosphere/year

24 Suspended Particulate Matter (PM 10 ) Properties: particles suspended in air (<10 um) Effects: lung damage, mutagenic, carcinogenic, teratogenic Sources: burning coal or diesel, volcanoes, factories, unpaved roads, plowing, lint, pollen, spores, burning fields Class: SPM: dust, soot, asbestos, lead, PCBs, dioxins, pesticides EPA Standard: 50 ug/m 3 (annual mean)

25 Mobile Source Emissions: Fine Particulate Matter (PM 2.5 )

26 Sulfur Dioxide (SO 2 ) Properties: colorless gas with irritating odor Effects: produces acid rain (H 2 SO 4 ), breathing difficulties, eutrophication due to sulfate formation, lichen and moss are indicators Sources: burning high sulfur coal or oil, smelting or metals, paper manufacture Class: sulfur oxides EPA Standard: 0.3 ppm (annual mean) Combines with water and NH 4 to increase soil fertility

27 VOCs (Volatile Organic Compounds) Properties: organic compounds (hydrocarbons) that evaporate easily, usually aromatic Effects: eye and respiratory irritants; carcinogenic; liver, CNS, or kidney damage; damages plants; lowered visibility due to brown haze; global warming Sources: vehicles (largest source), evaporation of solvents or fossil fuels, aerosols, paint thinners, dry cleaning Class: HAPs (Hazardous Air Pollutants) –Methane –Benzene –Chlorofluorocarbons (CFCs), etc. Concentrations indoors up to 1000x outdoors 600 million tons of CFCs

28 Other Air Pollutants Carbon dioxideCarbon dioxide ChloroFluoroCarbonsChloroFluoroCarbons FormaldehydeFormaldehyde BenzeneBenzene AsbestosAsbestos ManganeseManganese DioxinsDioxins CadmiumCadmium Others not yet fully characterizedOthers not yet fully characterized

29 Formation & Intensity Factors Local climate (inversions, air pressure, temperature, humidity)Local climate (inversions, air pressure, temperature, humidity) Topography (hills and mountains)Topography (hills and mountains) Population densityPopulation density Amount of industryAmount of industry Fuels used by population and industry for heating, manufacturing, transportation, powerFuels used by population and industry for heating, manufacturing, transportation, power Weather: rain, snow,windWeather: rain, snow,wind Buildings (slow wind speed)Buildings (slow wind speed) Mass transit usedMass transit used EconomicsEconomics

30 Pollutants warm air cool air surface heated by sun warm air rises (incl. pollutants) cools off, mixes with air of equal density & disperses cool air warm air (inversion layer) surface cools rapidly (night) a layer of warm air overlays surface polluted surface air rises but cannot disperse  remains trapped Thermal Inversion

31 ...when polluted air is stagnant (weather conditions, geographic location) Los Angeles, CA Smog Forms

32 Primary Pollutants Secondary Pollutants Sources Natural Stationary CO CO 2 SO 2 NO NO 2 Most hydrocarbons Most suspended particles SO 3 HNO 3 H 2 SO 4 H2O2H2O2H2O2H2O2 O3O3O3O3PANs Most andsalts NO 3 – Mobile SO 4 2–

33 Photochemical Smog Primary Pollutants NO 2 + Hydrocarbons Auto Emissions UV radiation H 2 O + O 2 Secondary Pollutants HNO 3 O 3 nitric acidozone Photochemical Smog

34 Solar radiation Ultraviolet radiation NO Nitric oxide P h o t o c h e m i c a l S m o g H 2 O Water NO 2 Nitrogen dioxide Hydrocarbons O 2 Molecular oxygen HNO 3 Nitric acid PANs Peroxyacyl nitrates Aldehydes (e.g., formaldehyde) O 3 Ozone O Atomic oxygen Photochemical Smog

35 Indoor Air Pollution

36 Why is indoor air quality important? 70 to 90% of time spent indoors, mostly at home Many significant pollution sources in the home (e.g. gas cookers, paints and glues) Personal exposure to many common pollutants is driven by indoor exposure Especially important for susceptible groups – e.g. the sick, old and very young

37 Exposure Time spent in various environments in US and less-developed countries

38 House of Commons Select Committee Enquiry on Indoor Air Pollution (1991) “[There is] evidence that 3 million people have asthma in the UK… and this is increasing by 5% per annum.” “Overall there appears to be a worryingly large number of health problems which could be connected with indoor pollution and which affect very large numbers of the population.” [The Committee recommends that the Government] “develop guidelines and codes of practice for indoor air quality in buildings which specifically identify exposure limits for an extended list of pollutants…”

39 Sources of Indoor Air Pollutants Building materials Furniture Furnishings and fabrics Glues Cleaning products Other consumer products Combustion appliances (cookers and heaters) Open fires Tobacco smoking Cooking House dust mites, bacteria and moulds Outdoor air

40 Important Indoor Air pollutants Nitrogen dioxide Carbon monoxide Formaldehyde Volatile Organic Compounds (VOCs) House dust mites (and other allergens, e.g. from pets) Environmental tobacco smoke Fine particles Chlorinated organic compounds (e.g. pesticides) Asbestos and man-made mineral fibres Radon

41 Health Effects Nitrogen dioxide Respiratory irritant Elevated risk of respiratory illness in children, perhaps resulting from increased susceptibility to respiratory infection; inconsistent evidence for effects in adults Concentrations in kitchens can readily exceed WHO and EPA standards

42 Health Effects Carbon monoxide An asphyxiant and toxicant Hazard of acute intoxication, mostly from malfunctioning fuel-burning appliances and inadequate or blocked flues Possibility of chronic effects of long-term exposure to non- lethal concentrations, particularly amongst susceptible groups

43 Health Effects Formaldehyde Sensory and respiratory irritant and sensitizer Possible increased risk of asthma and chronic bronchitis in children at higher exposure levels Individual differences in sensory and other transient responses Caution over rising indoor concentrations

44 Health Effects Volatile Organic Compounds (VOCs) Occur in complex and variable mixtures Main health effects relate to comfort and well- being, but benzene (and other VOCs) are carcinogenic Concern about possible role of VOCs in the aetiology of multiple chemical sensitivity; also implicated in sick building syndrome

45 Health Effects House dust mites House dust mites produce Der p1 allergen, a potent sensitizer Good evidence of increased risk of sensitization with increasing allergen exposure, but this does not necessarily lead to asthma Small reductions in exposure will not necessarily lead to reduced incidence and/or symptoms Indoor humidity is important

46 Health Effects Fungi and bacteria Dampness and mould-growth linked to self- reported respiratory conditions, but little convincing evidence for association between measured airborne fungi and respiratory disease Insufficient data to relate exposure to (non- pathogenic) bacteria to health effects in the indoor environment

47 Health Effects Environmental tobacco smoke (ETS) Sudden infant death syndrome Lower respiratory tract illness Middle ear disease Asthma 12 million children exposed to secondhand smoke in homes

48 Health Effects Fine particles Consistent evidence that exposure to small airborne particles (e.g. PM10) in ambient air can impact on human health; mechanisms uncertain Chronic Obstructive Pulmonary Disease and Cardiovascular Disease patients and asthmatics probably at extra risk Relative importance of indoor sources is unknown

49 Health Effects Radon Can cause lung cancer Estimated that 7,000 to 30,000 Americans die each year from radon-induced lung cancer Only smoking causes more lung cancer deaths Smokers more at risk than non-smokers

50 Radon Risk: Non-Smoker Radon Level (pCI/L) If 1000 people who did not smoke were exposed to this level over a lifetime.. About X would get lung cancer This risk of cancer from radon exposure compares to … What to do: 208Being killed in a violent crime Fix your home 104Fix your home 8310x risk of dying in a plane crash Fix your home 42Risk of drowningFix your home 2<1Risk of dying in a home fire Fix your home 1.3<1Average indoor radon level Fix your home.4<1Average indoor radon level Fix your home If you are a former smoker, your risk may be higher

51 Radon Risk: Smoker Radon Level (pCI/L) If 1000 people who smoke were exposed to this level over a lifetime.. About X would get lung cancer This risk of cancer from radon exposure compares to … What to do: Stop smoking and … x risk of drowningFix your home x risk of dying in a home fire Fix your home 857Fix your home x risk of dying in a plane crash Fix your home 2152x the risk of dying in a car crash Fix your home 1.39Average indoor radon level Fix your home.43Average indoor radon level Fix your home If you are a former smoker, your risk may be lower

52 Radon 55% of our exposure to radiation comes from radon colorless, tasteless, odorless gas formed from the decay of uranium found in nearly all soils levels vary

53 (From: Zone pCi/L 1 > <2

54 Radon: How it Enters Buildings Cracks in solid floors Construction joints Cracks in walls Gaps in suspended floors Gaps around service pipes Cavities inside walls The water supply

55 Radon: Reducing the Risks Sealing cracks in floors and walls Simple systems using pipes and fans More information: ch

56 Sick Building Syndrome (SBS) vs Building Related Illness (BRI)

57 Sick Building Syndrome A persistent set of symptoms in > 20% population Causes(s) not known or recognizable Complaints/Symptoms relieved after exiting building

58 Complaints/Symptoms Headaches Fatigue Reduced Mentation Irritability Eye, nose or throat irritation Dry Skin Nasal Congestion Difficulty Breathing Nose Bleeds Nausea

59 Building Related Illness Clinically Recognized Disease Exposure to indoor air pollutants Recognizable Causes

60 Clinically Recognized Diseases –Pontiac Fever – Legionella spp. –Legionnaire's Disease –Hypersensitivity Pneumonitis –Humidifier Fever –Asthma –Allergy –Respiratory Disease Chronic Obstructive Pulmonary Disease

61 Ventilation

62 Movement of Air Into / Out of Homes Amount of air available to dilute pollutants –important indicator of the likely contaminant concentration Indoor air can mix with outside air by three mechanisms –infiltration –natural ventilation –forced ventilation

63 Movement of Air Into / Out of Homes Infiltration –natural air exchange that occurs between a building and its environment when the doors and windows are closed –leakage through holes or openings in the building envelope –pressure induced due to pressure differentials inside and outside of the building especially important with cracks and other openings in wall

64 Movement of Air Into / Out of Homes Infiltration –Temperature induced (stack effect) driven by air movement through holes in floors, ceilings in winter, warm air in a building wants to rise, exits through cracks in ceiling and draws in

65 Movement of Air Into / Out of Homes Natural ventilation –air exchange that occurs when windows or doors are opened to increase air circulation Forced ventilation –mechanical air handling systems used to induce air exchange using fans and blowers Trade-offs –cut infiltration to decrease heating and cooling costs vs. indoor air quality problems

66 Movement of Air Into / Out of Homes Infiltration rates –Influenced by how fast wind is blowing, pressure differentials temperature differential between inside and outside of house location of leaks in building envelope

67 Greenhouse Effect

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70 Natural Greenhouse Effect With Greenhouse Effect average global temperature 60 degrees Without it, Earth would be a frigid planet, with average temperature around zero degrees Fahrenheit

71 Global Warming CO 2 CFCs CH 4 Increased Greenhouse Gases in the Troposphere Excess heat

72 Greenhouse Gases Carbon dioxide Methane Nitrous oxide Ozone CFC’s Hydrofluorocarbons Perfluorinated carbons Water vapour

73 Average Temperature Over Past 900,000 Years Thousands of Years Ago Average Surface Temperature (°C) Present

74 Temperature Change Over Past 22,000 Years Years Ago Temperature Change (°C) 20,00010,0002,0001, Now End of last ice age Agriculture established Average temperature over past 10,000 years = 15°C (59°F)

75 Average Temperature Over Past 130 Years Year Average Surface Temperature (°C)

76 Is this increase in temperature natural or ?

77 Carbon dioxide Temperature change End of last ice age Thousands of Years Before Present Concentration of CO 2 in the Atmosphere (ppm) –10.0 –7.5 –5.0 – Variation of temperature (˚C) from current level

78 Year Index (1900 = 100) Carbon dioxide Methane Nitrous oxide

79 Measurements made at Mauna Loa, Hawaii; elevation = 12,000 feet

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81 Contribution to Greenhouse Effect

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83 Methane Core samples taken from old ocean sediment layers have been used to trace back in time the climate changes that have occurred over the past tens of millions of years short periods of only a few hundred years in the geological past when rapid increases of the Earth's temperature have occurred superimposed on top of the rise and fall of average temperatures over the longer term up to 15 degrees centigrade warmer than today.

84 Methane Temperatures then fell back to the long term trend, the whole rise and fall only lasting a few hundred years. The most likely cause of this rapid global warming over such a short period is the release of methane into the atmosphere. Methane is 60 times more powerful than CO2 as a greenhouse gas Methane was released due to breakdown of material associated with permafrost

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86 Year Change in Temperature (ºC) Predictions of Future Warming?

87 Top Greenhouse Gas Emitters 19.1 % - United States 9.9% - China 5.1% - Japan 4.3% - Brazil 3.8 % - Germany 3.7% - Japan 2.4% - United Kingdom 1.9% - Indonesia 1.7% - Italy

88 What impacts have occurred and are predicted to occur from global warming? ?

89 Atmosphere Impacts from Global Warming? Weather Ocean currents Sea level Water resources Biodiversity Forests Human health Agriculture Human demographics

90 Increased deaths from heat and disease Disruption of food and water supplies Spread of tropical diseases to temperate areas Increased respiratory disease Increased water pollution from coastal flooding Human Health Rising sea levels Flooding of low-lying islands and coastal cities Flooding of coastal estuaries, wetlands, and coral reefs Beach erosion Disruption of coastal fisheries Contamination of coastal aquifiers with salt water Sea Level and Coastal Areas Changes in forest composition and locations Disappearance of some forests Increased fires from drying Loss of wildlife habitat and species Forests Changes in water supply Decreased water quality Increased drought Increased flooding Water Resources Shifts in food-growing areas Changes in crop yields Increased irrigation demands Increased pests, crop diseases, and weeds in warmer areas Agriculture Extinction of some plant and animal species Loss of habitats Disruption of aquatic life Biodiversity Prolonged heat waves and droughts Increased flooding More intense hurricanes, typhoons, tornadoes, and violent storms Weather Extremes Increased deaths More environmental refugees Increased migration Human Population

91 Direct manifestations Heat waves and periods of unusually warm weather Sea level rise and coastal flooding Glaciers melting Arctic and Antarctic warming with ice shelves breaking up Increase severity of weather Zooplankton are dying in the Pacific Ocean

92 Heat wave kills 30, no relief in sight July 27, 1999

93 Monster iceberg breaks off Antarctic ice shelf May 10, 2002

94 Antarctica Cold water melting from Antarctica's ice cap and icebergs falls to the ocean floor and surges northward, affecting worldwide circulation. Cold water melting from Antarctica's ice cap and icebergs falls to the ocean floor and surges northward, affecting worldwide circulation. Greenland

95 Today’s sea level Years before presentPresent 250,000200,000150,000100,00050,0000 –130 0 –426 0 Height above or below present sea level (meters) Height below present sea level (feet)

96 If all the ice on Greenland melted, world sea levels would rise about six metres (20 feet) If all the ice on the Antarctic continent melted, sea levels would rise over 70 metres (230 feet) This is unlikely to happen, but small increases will continue.

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101 Possible Consequences Spreading disease Earlier spring arrival Plant and animal range shifts and population declines Coral reef bleaching Downpours, heavy snowfalls, and flooding Droughts and fires

102 Global warming may harm human health November 16, 1998 Climatic changes related to global warming could foster dangerous outbreaks of cholera, dengue fever and malaria, …

103 Study: Global warming spurs migrations Thursday, January 2, 2003 Rising global temperatures that have lured plants into early bloom and birds to nest earlier in the spring are altering the ranges and behavior of hundreds of plant and animal species worldwide, two studies conclude.

104 Report: Coral bleaching hits record level May 19, 1999 Global warming has been linked to an unprecedented episode of coral bleaching in 1998, …

105 Vicious cycle: Global warming feeds fire potential November 2, 2000 Global warming may greatly accelerate the fire cycle in the desert ecosystem of North America, according to a study published today in the journal Nature. Elevated carbon dioxide levels, the result of increased fossil fuel burning, can alter the delicate balance of grasses in desert areas, the report notes. This finding may have major implications for the biodiversity and health of desert ecosystems in the western United States. "This could be a real problem for land managers," said Stan Smith, a professor of biology at the University of Nevada in Las Vegas and lead author of the study.

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107 Anomaly = difference between actual value and some mean value; in this case the mean is a 30 year average

108 Warmest Years on Record

109 Ozone Hole

110 Understanding Ozone Discovered in 1839 by German scientist Christian Friedrich Schonbein Pale blue, unstable molecule made of three oxygen atoms Vital to life in the stratosphere Harmful to plants and humans in the troposphere Concentration: stratosphere  up to 15 ppm at about 25 km Formed when atomic oxygen (O) from higher parts of the atmosphere collides with molecular oxygen (O 2 ) in the stratosphere UV radiation splits the ozone back to O and O 2 and it can form another ozone molecule

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113 The Ozone Hole First discovered in 1985: observations from Antarctica extend back into 1950’s. Characterized as a rapid depletion of ozone over Antarctica during spring. –Ozone hole season, Spring (August – October) –Ozone hole located over mainly over Antarctica. –Ozone hole recovers by late December Ozone hole caused by human chemicals (CFC’s) Ozone hole not present in early 1970’s

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116 science.widener.edu/svb/ atmo_chem/oct15.html

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118 Ozone hole stabilizes October 17, 2001 WASHINGTON (CNN) -- A hole in the Earth's protective ozone layer is about the same size as in the past three years, according to scientists at the National Oceanic and Atmospheric Administration, who predict it will hold steady in the near future. Satellite data show the hole over Antarctica, which allows more harmful solar radiation to reach the Earth, peaked this year at about 10 million square miles (26 million square km), roughly the size of North America.

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120 History of Ozone Depletion CFCs developed in 40’s and 50’sCFCs developed in 40’s and 50’s –Refrigerants, propellants, fire retardants 1970’s CFCs detected in atmosphere.1970’s CFCs detected in atmosphere. –Many of these have long atmospheric lifetimes (10’s to 100’s of years) 1974 Rowland and Molina propose that CFC’s can destroy ozone in the stratosphere.1974 Rowland and Molina propose that CFC’s can destroy ozone in the stratosphere. –CFCs broken apart by UV radiation forming chlorine which can destroy ozone quickly: O 3 +Cl  ClO+ O 2 (Catalytic Reaction) ClO+O  Cl+O 2

121 Chlorofluorocarbons or CFCs First produced by General Motors Corporation in 1928, CFCs were created as a replacement to the toxic refrigerant ammoniaFirst produced by General Motors Corporation in 1928, CFCs were created as a replacement to the toxic refrigerant ammonia CFCs have also been used as a propellant in spray cans, cleaner for electronics, sterilant for hospital equipment, and to produce the bubbles in StyrofoamCFCs have also been used as a propellant in spray cans, cleaner for electronics, sterilant for hospital equipment, and to produce the bubbles in Styrofoam

122 CFCs are cheap to produce and very stable compounds, lasting up to 200 years in the atmosphere Many countries have recently passed laws banning nonessential use of these chemicals. Nevertheless, by 1988 some 320,000 metric tons of CFCs were used worldwide.

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125 Action of CFCs CFCs created at the Earth's surface drift slowly upward to the stratosphere where UV radiation from the sun causes their decomposition and the release of chlorineCFCs created at the Earth's surface drift slowly upward to the stratosphere where UV radiation from the sun causes their decomposition and the release of chlorine Chlorine in turn attacks the molecules of ozone converting them into oxygen moleculesChlorine in turn attacks the molecules of ozone converting them into oxygen molecules Cl + O 3 »»» ClO + O 2 ClO + O »»» Cl + O 2

126 Ultraviolet light hits a chlorofluorocarbon (CFC) molecule, such as CFCl 3, breaking off a chlorine atom and leaving CFCl 2. UV radiation Sun Once free, the chlorine atom is off to attack another ozone molecule and begin the cycle again. A free oxygen atom pulls the oxygen atom off the chlorine monoxide molecule to form O 2. The chlorine atom and the oxygen atom join to form a chlorine monoxide molecule (ClO) The chlorine atom attacks an ozone (O 3 ) molecule, pulling an oxygen atom off it and leaving an oxygen molecule (O 2 ). Cl C F O O O O O O O O O O

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128 A single chlorine atom removes about 100,000 ozone molecules before it is taken out of operation by other substances

129 Current measurements indicate that the amount of ozone in the stratosphere of the low and middle latitudes has decreased by about 3% with estimates that it will decrease by10% by 2025 Low and Middle Latitudes

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131 Harmful effects of UV radiation. Skin cancer (ultraviolet radiation can destroy acids in DNA) Cataracts and sun burning Suppression of immune systems Adverse impact on crops and animals Reduction in the growth of ocean phytoplankton Cooling of the Earth's stratosphere and possibly some surface climatic effect Degradation of paints and plastic material

132 matrix.ucdavis.edu/tumors/tradition/ gallery-ssmm.html

133 cataract.asp

134 Conclusion Ozone Depletion Exists and effects certain areas of the Earth more than others Currently, one in five North Americans and one in two Australians will develop some form of skin cancer in their lifetime With a sustained 10% decrease in stratospheric ozone, an additional 300,000 non- melanoma and 4,500 melanoma skin cancers could be expected world-wide, according to UNEP estimates.

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136 Acid Deposition

137 Measuring Acid Rain Acid rain is measured using a "pH" scale. –The lower a substance's pH, the more acidic it is. Pure water has a pH of 7.0. – Normal rain is slightly acidic and has a pH of about 5.6 Any rainfall has a pH value less than 5.6 is defined as acid rain As of the year 2000, the most acidic rain falling in the US has a pH of about 4.3.

138 Two Forms… Wet Refers to acid rain, fog, sleet, cloud vapor and snow. Dry Refers to acidic gases and particles.

139 Compounds Two main contributers to acid deposition: Sulfur Dioxide (SO 2 ) Nitrogen Oxides (NO x ) * 66% of all sulfur dioxides and 25% of all nitrogen oxides comes from electric power generation that produces energy by burning fossil fuels.

140 When gas pollutants e.g. sulphur dioxide, nitrogen dioxide dissolve in rain water, various acids are formed. CO 2 + H 2 O  H 2 CO 3 (carbonic acid) SO 2 + H 2 O  H 2 SO 3 (sulphorous acid) NO 2 + H 2 O  HNO 2 (nitrous acid) + HNO 3 (nitric acid)

141 Causes of Acid Rain Sulfur dioxide (SO 2 ) and nitrogen oxides (NO x ) are the primary causes of acid rain. In the US, About 2/3 of all SO 2 and 1/4 of all NO x comes from electric power generation that relies on burning fossil fuels like coal.

142 Acidic Precipitation Fossil fuels Power plants Industrial emissions Auto emissions Primary Pollutants SO 2 NO 2 Secondary Pollutants H 2 SO 4 HNO 2 sulfuric acidnitric acid soils leaching of minerals vegetation direct toxicity indirect health effects water sediments leaching aluminum acidic precipitation

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144 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) AcidicPrecipitation

145 Fig , p. 428 BIOL 349 Atmosphere

146 Sulphur dioxide emission (1997)

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148 “Wet” Acid Rain Acidic water flows over and through the ground, it affects a variety of plants and animals.

149 “Dry” Acid Rain Dry deposition refers to acidic gases and particles. About half of the acidity in the atmosphere falls back to earth through dry deposition. The wind blows these acidic particles and gases onto buildings, cars, homes, and trees.

150 Increased Acidity Dry deposited gases and particles can also be washed from trees and other surfaces by rainstorms. The runoff water adds those acids to the acid rain, making the combination more acidic than the falling rain alone.

151 Effects of Acid Rain The strength of the effects depend on many factors –How acidic the water is –The chemistry and buffering capacity of the soils involved –The types of fish, trees, and other living things that rely on the water

152 Effects of Acid Rain Has a variety of effects, including damage to forests and soils, fish and other living things, materials, and human health. Also reduces how far and how clearly we can see through the air, an effect called visibility reduction. Effects of acid rain are most clearly seen in the aquatic environments Most lakes and streams have a pH between 6 and 8

153 Buffering Capacity Acid rain primarily affects sensitive bodies of water, which are located in watersheds whose soils have a limited "buffering capacity“ Lakes and streams become acidic when the water itself and its surrounding soil cannot buffer the acid rain enough to neutralize it.

154 In areas where buffering capacity is low, acid rain also releases aluminum from soils into lakes and streams; aluminum is highly toxic to many species of aquatic organisms.

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156 Effects on Wildlife Generally, the young of most species are more sensitive to environmental conditions than adults. At pH 5, most fish eggs cannot hatch. At lower pH levels, some adult fish die. Some acid lakes have no fish.

157 Effects on Wildlife Both low pH and increased aluminum levels are directly toxic to fish. In addition, low pH and increased aluminum levels cause chronic stress that may not kill individual fish, but leads to lower body weight and smaller size and makes fish less able to compete for food and habitat.

158 Acid Rain and Forests Acid rain does not usually kill trees directly. Instead, it is more likely to weaken trees by damaging their leaves, limiting the nutrients available to them, or exposing them to toxic substances slowly released from the soil.

159 Germany Mongolia

160 Effects of Acid Rain Great Smoky Mountains, NC

161 Nutrients Acidic water dissolves the nutrients and helpful minerals in the soil and then washes them away before trees and other plants can use them to grow. Acid rain also causes the release of substances that are toxic to trees and plants, such as aluminum, into the soil.

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163 Air Pollution Prevention

164 Specific Air Pollution Treatment Technology Traditional –Move factory to remote location –Build taller smokestack so wind blows pollution elsewhere New –Biofiltration : vapors pumped through soil where microbes degrade –High-energy destruction: high-voltage electricity –Membrane separation: diffusion of organic vapors through membrane –Oxidation: High temperature combustor

165 Absorption

166 Adsorption

167 Combustion

168 Cyclone

169 Filtration

170 Electrostatic Precipitator

171 Liquid Scrubber

172 Sulfur Dioxide Control

173 Air Pollution Results

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175 Comparison of 1970 and 1999 Emissions

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179 Number of People Living in Counties with Air Quality Concentrations Above the Level of the National Ambient Air Quality Standards (NAAQS) in 1999

180 Trends in Sulfur Dioxide Emissions Following Implementation of Phase I of the Acid Rain Program: Total State-level Utility SO2 (1980, 1990, 1999)

181 Fifty Years of Air Pollution Figures are in millions of metric tons per year

182 Mobile Sources: The Last Ten Years -10% -29% -8% -85% -3% -24% VOCs CO NO x PM 10 SO x Lead Percent reductions shown are based on estimates of tons/year from mobile sources over the time period

183 Who is Affected by Air Pollution? Ozone CO NO 2 PM 10 SO 2 Lead Millions of people living in counties with air quality that exceeds each NAAQS (1990 data) Over 74 million people are subjected to high levels of at least one of these pollutants

184 Milestones in the Control of Automotive Emissions Autos linked to air pollution Original CAA, PCV valves HC & CO exhaust controls CAA amendments, EPA formed Evaporative controls First I/M Program NOx exhaust controls First catalytic converters New cars meet statutory limits Volatility limits on gasoline New CAA Amendments

185 1987 Montreal Protocol: CFC emissions should be reduced by 50% by the year 2000 (they had been increasing 3% per year.) 1990 London amendments: production of CFCs, CCl4, and halons should cease entirely by Copenhagen agreements: phase- out accelerated to 1996.

186 What is the Kyoto Protocol? How did we get to Kyoto? What are the goals of Kyoto? Is Kyoto enough?

187 Steps to Kyoto 1985 International Council of Scientific Unions (Prof. Bert Bolin) “Many important economic and social decisions are being made today on long term projects, all based on the assumption that past climatic data, without modification, are a reliable guide to the future. This is no longer a good assumption”

188 Steps to Kyoto Toronto - creation of IPCC warmest summer to date, international meeting in Toronto Intergovernmental Panel on Climate Change formed First report (FAR) overview of the current science of climate change

189 IPCC IPCC headed by Prof. Bert Bolin 3 working groups Climate Science Climate Impacts Response Strategies FAR used in Earth Summit meeting in Rio - United Nations Framework Convention on Climate Change

190 IPCC 1995 IPCC Second Assessment Report (SAR) completed, published in 1996 WG I Climate Science WG II Impact, Adaptation and Mitigation WG III Economic and Social Dimensions “The balance of evidence suggests a discernible human influence on global climate”

191 IPCC 1997 Kyoto meeting - binding targets set culmination of a series of meetings since Rio (1992) 2001 Bonn - rescuing Kyoto 2001 IPCC Third Assessment Report (TAR) WG I Climate Science WG II Vulnerabilities, Impacts and Adaptation WG III Mitigation

192 IPCC TAR (2001) “There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities” (WG I) Global losses in weather related natural disasters have increased ten-fold from the 1960s to the 1990s, and that a portion of this increase must be due to increases in frequency and intensity of some extreme events. (WG II) “most of the opportunities to reduce emissions will come from energy efficiency gains and in reducing release of greenhouse gases from industry” (WG III)

193 Goals of Kyoto Protocol Reduction of greenhouse gases to below 1990 levels: 5.2% world wide reduction on average by % for Canada by When sufficient countries ratify the Protocol (at least 55 countries comprising at least 55% of emissions), Protocol comes into effect USA - 25% of emissions

194 Kyoto Emissions Agreement

195 Annex B CountriesNon Annex B Countries Fossil-Fuel CO 2 Emissions Fossil-Fuel CO 2 Emissions (million metric tonnes C) Bunkers Bunkers (million metric tonnes C) Fossil-Fuel CO 2 Emissions (million metric tonnes C) Bunkers (million metric tonnes C) Source: Gregg Marland and Tom Boden (CDIAC, Oak Ridge National Laboratory).CDIAC

196 Greenhouse Effect - Conclusion Since 1700, humans have directly or indirectly caused the concentration of the major greenhouse gases to increaseSince 1700, humans have directly or indirectly caused the concentration of the major greenhouse gases to increase Scientists predict that this increase may enhance the greenhouse effect making the planet warmer by 0.3 to 0.6 degrees CelsiusScientists predict that this increase may enhance the greenhouse effect making the planet warmer by 0.3 to 0.6 degrees Celsius

197 Cost of Regular Gasoline $3.80 – Great Britain $3.80 – The Netherlands $3.74 – Italy $3.69 – Belgium $3.62 – France $3.57 – Germany $3.20 – Japan $1.39 – United States in U.S. dollars as of October 13, 1997

198 History of Global Warming 1904: Swedish scientist Svante Arrhenius was, according to NASA, "the first person to investigate the effect that doubling atmospheric carbon dioxide would have on global climate."

199 History of Global Warming Arrhenius began studying rapid increases in anthropogenic – carbon emissions, determining that "the slight percentage of carbonic acid in the atmosphere may, by the advances of industry, be changed to a noticeable degree in the course of a few centuries."

200 History of Global Warming The unique research of Arrhenius suggested that this increase could be beneficial, making Earth's climates "more equable" and stimulating plant growth and food production. Until about 1960, most scientists thought it implausible that humans could actually affect average global temperatures.

201 History of Global Warming 1950s: Geophysicist Roger Revelle, with the help of Hans Suess, demonstrated that carbon dioxide levels in the air had increased as a result of the use of fossil fuels.

202 History of Global Warming 1965: Serving on the President's Science Advisory Committee Panel on Environmental Pollution in 1965, Roger Revelle helped publish the first high-level government mention of global warming. The book-length report identified many of the environmental troubles the nation faced, and mentioned in a "subpanel report" the potential for global warming by carbon dioxide.

203 History of Global Warming 1977: "In 1977 the nonpartisan National Academy of Sciences issued a study called Energy and Climate, which carefully suggested that the possibility of global warming 'should lead neither to panic nor to complacency.'

204 History of Global Warming Rather, the study continued, it should 'engender a lively sense of urgency in getting on with the work of illuminating the issues that have been identified and resolving the scientific uncertainties that remain.'

205 History of Global Warming As is typical with National Academy studies, the primary recommendation was for more research." — From "Breaking the Global-Warming Gridlock" by Daniel Sarewitz and Roger Pielke Jr., THE ATLANTIC, July 2000

206 History of Global Warming Roger Revelle chaired the National Academy Panel, which found that about forty percent of the anthropogenic carbon dioxide has remained in the atmosphere, two-thirds from fossil fuel and one-third from the clearing of forests. It is now known that carbon dioxide is one of the primary greenhouse gases that contributes to global warming and remains in the atmosphere for a century.

207 History of Global Warming 1980s: Representative Al Gore (D- TN), who had been a student of Revelle's, co-sponsored the first Congressional hearings to study the implications of global warming and to encourage the development of environmental technologies to combat global warming.

208 History of Global Warming 1982: Roger Revelle published a widely-read article in SCIENTIFIC AMERICAN addressing the rise in global sea level and the "relative role played by the melting of glaciers and ice sheets versus the thermal expansion of the warming surface waters."

209 History of Global Warming 1983: The Environmental Protection Agency released a report detailing some of the possible threats of the anthropogenic emission of carbon dioxide.

210 History of Global Warming 1988: NASA climate scientist James Hansen and his team reported to Congress on global warming, explaining, "the greenhouse warming should be clearly identifiable in the 1990s" and that "the temperature changes are sufficiently large to have major impacts on people and other parts of the biosphere, as shown by computed changes in the frequency of extreme events and comparison with previous climate trends."

211 History of Global Warming With the increased awareness of global warming issues, the Intergovernmental Panel on Climate Change (IPCC) was established by the World Meteorological Organization and the United Nations Environment Programme to assess scientific, technical and socio-economic information relevant for the understanding of climate change, its potential impacts and options for adaptation and mitigation. The IPCC was the first international effort of this scale to address environmental issues.

212 History of Global Warming 1990: Congress passed and President George Bush signed Public Law "The Global Change Research Act of The purpose of the legislation was "…to require the establishment of a United States Global Change Research Program aimed at understanding and responding to global change, including the cumulative effects of human activities and natural processes on the environment, to promote discussions towards international protocols in global change research, and for other purposes."

213 History of Global Warming As part of the Act, the Global Change Research Information Office (GCRIO) was established "to disseminate to foreign governments, businesses, and institutions, as well as citizens of foreign countries, scientific research information available in the United States which would be useful in preventing, mitigating, or adapting to the effects of global change. The office began formal operation in 1993.As part of the Act, the Global Change Research Information Office (GCRIO) was established "to disseminate to foreign governments, businesses, and institutions, as well as citizens of foreign countries, scientific research information available in the United States which would be useful in preventing, mitigating, or adapting to the effects of global change. The office began formal operation in 1993.

214 History of Global Warming 1992: In June of 1992, over 100 government leaders, representatives from 170 countries, and some 30,000 participants met in Rio de Janeiro at the U.N. Conference on Environment and Development (UNCED or the "Earth Summit").

215 History of Global Warming There, an international assembly formally recognized the need to integrate economic development and environmental protection into the goal of sustainable development.

216 History of Global Warming 1997: In December, 1997, more than 160 nations met in Kyoto, Japan, to negotiate binding limitations on greenhouse gases for the developed nations, pursuant to the objectives of the Framework Convention on Climate Change of 1992.

217 History of Global Warming The outcome of the meeting was the Kyoto Protocol, in which the developed nations agreed to limit their greenhouse gas emissions, relative to the levels emitted in The United States agreed to reduce emissions from 1990 levels by 7 percent during the period 2008 to 2012.

218 History of Global Warming 1997: In December, 1997, more than 160 nations met in Kyoto, Japan, to negotiate binding limitations on greenhouse gases for the developed nations, pursuant to the objectives of the Framework Convention on Climate Change of 1992.

219 History of Global Warming The outcome of the meeting was the Kyoto Protocol, in which the developed nations agreed to limit their greenhouse gas emissions, relative to the levels emitted in The United States agreed to reduce emissions from 1990 levels by 7 percent during the period 2008 to 2012.

220 History of Global Warming Also that year, the United States Senate unanimously passed the Hagel-Byrd Resolution notifying the Clinton Administration that the Senate would not ratify any treaty that would (a) impose mandatory greenhouse gas emissions reductions for the United States without also imposing such reductions for developing nations, or (b) result in serious harm to our economy.

221 History of Global Warming 2001: The IPCC released its third assessment report, concluding on the basis of "new and stronger evidence that most of the observed warming over the last 50 years is attributable to human activities." They also observed that "the globally averaged surface temperature is projected to increase by 1.4 to 5.8 degrees Celsius over the period 1990 to 2100."

222 History of Global Warming The same year, President George W. Bush announced that the United States would not ratify the Kyoto Protocol. The Protocol is now in limbo until one of the two crucial holdouts — Russia or the United States — will ratify the treaty.

223 History of Global Warming 2003: Senator John McCain (R- AZ) and Senator Joseph Lieberman (D-CT) co-sponsored a proposal for mandatory caps on "greenhouse gas" emissions from utilities and other industries.

224 History of Global Warming Although the proposal was rejected in the Senate by a margin of 55 to 43, it was the Senators' first attempt to garner Senate attention for the issue of global warming, and McCain and Lieberman were encouraged by the support for the measure.


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