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Air Pollution, Climate Change, and Ozone Depletion

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Title: Air Pollution, Climate Change, and Ozone Depletion


1
Air Pollution, Climate Change, and Ozone Depletion
  • Chapter 12

2
12-1 What Is the Nature of the Atmosphere?
  • Concept 12-1 The atmosphere is structured in
    layers, including the troposphere, which supports
    life, and the stratosphere, which contains the
    protective ozone layer.

3
The Atmosphere Consists of Several Layers (1)
  • Atmosphere varies in
  • Density
  • Atmospheric pressure

4
The Atmosphere Consists of Several Layers (2)
  • Troposphere
  • 7580 of the earths air mass
  • Closet to the earth's surface
  • Chemical composition of air
  • Rising and falling air currents weather and
    climate
  • Involved in chemical cycling

5
The Stratosphere Is Our Global Sunscreen
  • Stratosphere
  • Similar composition to the troposphere, with 2
    exceptions
  • Much less water
  • O3, ozone layer, filters UV
  • Location

6
Earth Has Many Different Climates (1)
  • Weather
  • Climate
  • Air circulation in lower atmosphere due to
  • Uneven heating of the earths surface by the sun
  • Rotation of the earth on its axis
  • Properties of air, water, and land

7
Earth Has Many Different Climates (2)
  • Currents
  • Prevailing winds
  • Earths rotation
  • Redistribution of heat from the sun
  • Link between air circulation, ocean currents, and
    biomes

8
Greenhouse Gases Warm the Lower Atmosphere
  • Greenhouse gases
  • H2O
  • CO2
  • CH4
  • N2O
  • Greenhouse effect
  • Human-enhanced global warming

9
12-2 What Are the Major Outdoor Pollution
Problems?
  • Concept 12-2 Pollutants mix in the air to form
    industrial smog, resulting mostly from burning
    coal, and photochemical smog, caused by motor
    vehicle, industrial, and power plant emissions.

10
Air Pollution Comes from Natural and Human
Sources (1)
  • Air pollution
  • Natural sources
  • Dust blown by wind
  • Pollutants from wildfires and volcanoes
  • Volatile organics released by plants
  • Withdrawing groundwater

11
Air Pollution Comes from Natural and Human
Sources (2)
  • Human sources mostly in industrialized and/or
    urban areas
  • Stationary sources
  • Mobile sources

12
Air Pollution Comes from Natural and Human
Sources (3)
  • Primary pollutants
  • Secondary pollutants
  • Air quality improving in developed countries
  • Much more needs to be done in developing
    countries
  • Indoor pollution big threat to the poor

13
Burning Coal Produces Industrial Smog
  • Chemical composition of industrial smog
  • Reduction of this smog in urban cities of the
    United States
  • China and smog
  • Human deaths

14
Sunlight Plus Cars Equals Photochemical Smog
  • Photochemical Smog
  • Chemical composition
  • Sources
  • VOCs NO2 Heat Sunlight yields
  • Ground level O3 and other photochemical oxidants
  • Aldehydes
  • Other secondary pollutants
  • Human health and environmental impact

15
Several Factors Can Decrease or Increase Outdoor
Air Pollution (1)
  • Outdoor air pollution may be decreased by
  • Settling of particles due to gravity
  • Rain and snow
  • Salty sea spray from the ocean
  • Winds
  • Chemical reactions

16
Several Factors Can Decrease or Increase Outdoor
Air Pollution (2)
  • Outdoor air pollution may be increased by
  • Urban buildings
  • Hills and mountains
  • High temperatures
  • Emissions of VOCs from certain trees and plants
  • Grasshopper effect
  • Temperature inversions

17
12-3 What Is Acid Deposition and Why Is It a
Problem?
  • Concept 12-3 Acid deposition is caused mainly by
    coal-burning power plant and motor vehicle
    emissions in some regions, it threatens human
    health, aquatic life and ecosystems, forests, and
    human-built structures.

18
Acid Disposition Is a Serious Regional Air
Pollution Problem
  • Acid deposition, acid rain
  • Formation
  • Local versus regional problems
  • Effects of prevailing winds
  • Buffers
  • Where is the worst acid deposition?

19
Acid Deposition Has a Number of Harmful Effects
(1)
  • Human respiratory disorders
  • Aquatic ecosystems affected
  • Release of toxic metals

20
Acid Deposition Has a Number of Harmful Effects
(2)
  • Leaching of soil nutrients
  • Loss of crops and trees
  • Damage to buildings, statues, and monuments

21
12-4 Why Is Indoor Air Pollution a Major Problem?
  • Concept 12-4 The major indoor air pollutants are
    smoke and soot from wood and coal fires (mostly
    in developing countries) and chemicals used in
    building materials and products, all of which
    threaten human health.

22
Indoor Air Pollution Is a Serious Problem (1)
  • Developing countries
  • Indoor burning
  • Poor suffer the greatest risk
  • Developed countries
  • Indoor air pollution is greater than outdoor air
    pollution

23
Indoor Air Pollution Is a Serious Problem (2)
  • Why?
  • 11 of the common air pollutants higher inside
    than outside
  • Greater in vehicles than outside
  • Health risks magnified people spend 7098 of
    their time is indoors

24
Indoor Air Pollution Is a Serious Problem (3)
  • Who are at greatest risk from indoor air
    pollution?
  • Children under 5 and the elderly
  • Sick
  • Pregnant women
  • People with respiratory disorders or heart
    problems
  • Smokers
  • Factory workers

25
Indoor Air Pollution Is a Serious Problem (4)
  • Four most dangerous indoor air pollutants
  • Tobacco smoke
  • Formaldehyde
  • Radioactive radon-222 gas
  • Very small particles
  • Sources of these pollutants
  • Human health risks

26
Indoor Air Pollution Is a Serious Problem (5)
  • Other possible indoor air pollutants
  • Pesticide residue
  • Pb particles
  • Living organisms and their excrements
  • E.g., Dust mites and cockroach droppings
  • Airborne spores of molds and mildews
  • Sick-building syndrome

27
Case Study Radioactive Radon Gas
  • Sources
  • Human health risks
  • Testing for radon
  • Correcting a radon problem

28
Your Bodys Natural Defenses against Air
Pollution Can Be Overwhelmed
  • Respiratory system protection from air pollutants
  • Role of cilia, mucus, sneezing, and coughing
  • Effect of smoking and prolonged air pollution
    exposure
  • Chronic bronchitis
  • Emphysema

29
Air Pollution Is a Big Killer
  • 3 Million deaths per year world-wide
  • Mostly in Asia
  • Main causes
  • EPA proposed stricter emission standards for
    diesel-powered vehicles
  • Link between international trade and air
    pollution
  • Cargo ships and pollution

30
12-5 How Should We Deal with Air Pollution?
  • Concept 12-5 Legal, economic, and technological
    tools can help to clean up air pollution, but
    much greater emphasis should be focused on
    preventing air pollution.

31
Laws and Regulations Can Reduce Outdoor Air
Pollution (1)
  • United States
  • Clean Air Acts 1970, 1977, and 1990
  • EPA
  • National ambient air quality standards (NAAQs)
    for 6 outdoor criteria pollutants
  • National emission standards for 188 hazardous air
    pollutants (HAPs)
  • Toxic Release Inventory (TRI)

32
Laws and Regulations Can Reduce Outdoor Air
Pollution (2)
  • Good news in U.S.
  • Decrease in emissions
  • Use of low-sulfur diesel fuel
  • Cuts pollution
  • Developing countries
  • More air pollution

33
Case Study Lead Can Be a Highly Toxic Pollutant
(1)
  • Does not break down in the environment
  • Sources
  • Human health and environmental impact
  • Most vulnerable

34
Case Study Lead Can Be a Highly Toxic Pollutant
(2)
  • Reduction of lead (Pb)
  • Unleaded gasoline
  • Unleaded paint
  • Still problems
  • 2007 toys with Pb paint recalled
  • Global ban on lead in gasoline and paint

35
Case Study U.S. Air Pollution Laws Can Be
Improved (1)
  • Rely on cleanup more than prevention of pollution
  • Raise fuel-efficiency for cars, SUVs, and light
    trucks
  • Better regulation of emissions of motorcycles and
    two-cycle gasoline engines
  • Regulate air pollution for oceangoing ships in
    American ports

36
Case Study U.S. Air Pollution Laws Can Be
Improved (2)
  • Why are airports exempt from many regulations?
  • Regulate greenhouse gas emissions
  • Ultrafine particles are not regulated
  • Urban O3 levels too high

37
Case Study U.S. Air Pollution Laws Can Be
Improved (3)
  • What about indoor air pollution?
  • Better enforcement of the Clean Air Acts
  • Is intense pressure needed from citizens to make
    improvements?

38
We Can Use the Marketplace to Reduce Outdoor Air
Pollution
  • Emission trading or cap-and-trade program
  • Mixed reactions to program
  • SO2 emissions down significantly
  • NO2 will be tried in the future

39
There Are Many Ways to Reduce Outdoor Air
Pollution
  • 1980 2006
  • SO2 emissions from U.S. electric power plants
    decreased by 66
  • NOx emissions by 41
  • Particulate emissions by 28
  • Older plants not governed by the same regulations
  • New cars have better emissions

40
Reducing Indoor Air Pollution Should Be a
Priority
  • Greater threat to human health than outdoor
    pollution
  • What can be done?
  • Prevention
  • Cleanup

41
We Need to Put More Emphasis on Pollution
Prevention
  • Output approaches
  • New shift to preventing outdoor and indoor
    pollution
  • Pressure from citizens

42
12-6 How Might the Earths Temperature and
Climate Change in the Future?
  • Concept 12-6A Evidence indicates that the
    earths atmosphere is warming, mostly because of
    human activities, and that this will lead to
    significant climate change during this century.
  • Concept 12-6B The projected rapid change in the
    atmospheres temperature could have severe and
    long-lasting consequences, including increased
    drought and floods, shifts in locations of
    agriculture and wildlife habitats, and rising sea
    levels.

43
Global Warming and Global Cooling Are Not New (1)
  • Over the past 4.7 billion years the climate has
    been altered by
  • Volcanic emissions
  • Changes in solar input
  • Movement of the continents
  • Impacts by meteors
  • Over the past 900,000 years
  • Glacial and interglacial periods

44
Global Warming and Global Cooling Are Not New (2)
  • Over the past 10,000 years
  • Interglacial period
  • Over the past 1,000 years
  • Temperature stable
  • Over the past 100 years
  • Temperature changes methods of determination

45
Human Activities Emit Large Quantities of
Greenhouses Gases (1)
  • Since the Industrial Revolution
  • CO2, CH4, and N2O emissions higher
  • Main sources agriculture, deforestation, and
    burning of fossil fuels
  • Correlation of rising CO2 and CH4 with rising
    global temperatures
  • Countries with the largest CO2 emissions

46
Human Activities Emit Large Quantities of
Greenhouses Gases (2)
  • Per capita emissions of CO2
  • Scientific and economic studies
  • 2007 Field and Marland
  • Tipping point
  • 2008 Aufhammer and Carson
  • Chinas CO2 emission growth may be underestimated
  • Ice core analysis of air pollutants

47
What Is the Scientific Consensus about Future
Temperature Change?
  • Mathematical models used for predictions
  • Global warming rapid rate
  • Human factors are the major cause of temperature
    rise since 1950
  • Human factors will become a greater risk factor

48
Can the Oceans Save Us?
  • Solubility of CO2 in ocean water
  • Warmer oceans
  • CO2 levels increasing acidity
  • Effect on atmospheric levels of CO2
  • Effect on coral reefs
  • Antarcticas Southern Ocean and the North
    Atlantic Ocean
  • Decrease in CO2 uptake
  • Significance on global CO2 levels

49
There Is Uncertainty about the Effects of Cloud
Cover on Global Warming
  • Warmer temperatures create more clouds
  • Thick, light-colored low altitude clouds
    decrease surface temperature
  • Thin, cirrus clouds at high altitudes increase
    surface temperature
  • Effect of jet entrails on climate temperature

50
Outdoor Air Pollution Can Temporarily Slow Global
Warming
  • Aerosol and soot pollutants
  • Will not enhance or counteract projected global
    warming
  • Fall back to the earth or are washed out of the
    lower atmosphere
  • Reduction especially in developed countries

51
Enhanced Global Warming Could Have Severe
Consequences (1)
  • Tipping point and irreversible climate change
  • Worst-case scenarios
  • Ecosystems collapsing
  • Low-lying cities flooded
  • Wildfires in forests
  • Prolonged droughts grasslands become dust bowls
  • More destructive storms
  • Glaciers shrinking rivers drying up

52
Enhanced Global Warming Could Have Severe
Consequences (2)
  • Accelerate global warming, lead to more drought
  • Biodiversity will decrease
  • NPP will decrease
  • Dry climate ecosystems will increase
  • Other effects of prolonged lack of water

53
Enhanced Global Warming Could Have Severe
Consequences (3)
  • Why will global warming be worse in the polar
    regions?
  • Important climate role of floating sea ice
  • Mountain glaciers affected by
  • Average snowfall
  • Average warm temperatures

54
Enhanced Global Warming Could Have Severe
Consequences (4)
  • Europes Alps
  • Glaciers are disappearing
  • South America
  • Glaciers are disappearing
  • Greenland
  • Warmer temperatures

55
Enhanced Global Warming Could Have Severe
Consequences (5)
  • Expansion of warm water
  • Melting of land-based ice
  • What about Greenland?

56
Enhanced Global Warming Could Have Severe
Consequences (6)
  • Projected irreversible effect
  • Degradation and loss of 1/3 of coastal estuaries,
    wetlands, and coral reefs
  • Disruption of coastal fisheries
  • Flooding of
  • Low-lying barrier islands and coastal areas
  • Agricultural lowlands and deltas
  • Contamination of freshwater aquifers
  • Submergence of low-lying islands in the Pacific
    and Indian Oceans and the Caribbean

57
Enhanced Global Warming Could Have Severe
Consequences (7)
  • Carbon present as CH4 in permafrost soils and
    lake bottoms
  • 2004 Arctic Climate Impact Assessment
  • 1020 of the permafrost might melt this century
  • Effect on global warming

58
Enhanced Global Warming Could Have Severe
Consequences (8)
  • Heat waves and droughts in some areas
  • Prolonged rains and flooding in other areas
  • Will storms get worse?
  • More studies needed
  • Hurricanes Katrina and Rita

59
Enhanced Global Warming Could Have Severe
Consequences (9)
  • Most susceptible ecosystems
  • Coral reefs
  • Polar seas
  • Coastal wetland
  • High-elevation mountaintops
  • Alpine and arctic tundra

60
Enhanced Global Warming Could Have Severe
Consequences (10)
  • What about
  • Migratory animals
  • Forests
  • Which organisms could increase with global
    warming? Significance?
  • Insects
  • Fungi
  • Microbes

61
Enhanced Global Warming Could Have Severe
Consequences (11)
  • Regions of farming may shift
  • Decrease in tropical and subtropical areas
  • Increase in northern latitudes
  • Less productivity soil not as fertile
  • Genetically engineered crops more tolerant to
    drought

62
Enhanced Global Warming Could Have Severe
Consequences (12)
  • Deaths from heat waves will increase
  • Deaths from cold weather will decrease
  • Higher temperatures can cause
  • Increased flooding
  • Increase in some forms of air pollution, more O3
  • More insects, microbes, toxic molds, and fungi

63
12-7 What Can We Do to Slow Climate Change?
  • Concept 12-7 We can slow the rate of global
    warming and climate change by sharply reducing
    greenhouse gas emissions, increasing energy
    efficiency, relying more on renewable energy
    resources, and slowing population growth.

64
What Are Our Options?
  • Two approaches
  • Drastically reduce the amount of greenhouse gas
    emissions
  • Devise strategies to reduce the harmful effects
    of global warming
  • Will we reach a political tipping point before we
    reach irreversible climate change tipping points?

65
We Can Reduce the Threat of Climate Change (1)
  • Input or prevention strategies
  • Improve energy efficiency to reduce fossil fuel
    use
  • Stop cutting down tropical forests
  • Output strategy
  • Capture and store CO2

66
We Can Reduce the Threat of Climate Change (2)
  • Output solutions
  • Massive global tree planting how many?
  • Wangari Maathai
  • Great Wall of Trees China and Africa
  • Plant fast-growing perennials on degraded land
  • Capturing and storing CO2

67
Is Capturing and Storing CO2 the Answer? (1)
  • Carbon capture and storage (CCS)
  • Several problems with this approach
  • Power plants using CCS
  • More expensive to build
  • None exist
  • Unproven technology
  • Large inputs of energy to work
  • Increasing CO2 emissions

68
Is Capturing and Storing CO2 the Answer? (2)
  • Problems with carbon capture and storage cont…
  • Promotes the continued use of coal (worlds
    dirtiest fuel)
  • Effect of government subsidies and tax breaks
  • Stored CO2 would have to remain sealed forever
    no leaking

69
Governments Can Help to Reduce the Threat of
Climate Change
  • Strictly regulate CO2 and CH4 as pollutants
  • Cap-and-trade approach
  • Increase subsidies to encourage use of
    energy-efficient technology
  • Technology transfer

70
Governments Can Enter into International Climate
Negotiations The Kyoto Protocol
  • 1997 Treaty to slow climate change
  • The Kyoto Protocol
  • Reduce emissions of CO2, CH4, and N2O by 2012 to
    levels of 1990
  • Trading greenhouse gas emissions among countries
  • Not signed by the U.S.
  • President G.W. Bushs reasons

71
We Can Move Beyond the Kyoto Protocol
  • 2004 Stewart and Wiener
  • New treaty needed
  • Should be led by the U.S.
  • Include the developing countries
  • Cap-and-trade emissions program
  • Set up 10 year goals

72
Some Governments, Corporations, and Individuals
Are Leading the Way (1)
  • Costa Rica goal to be carbon neutral by 2030
  • Norway aims to be carbon neutral by 2050
  • China and India must change energy habits
  • U.S. cities and states taking initiatives to
    reduce carbon emissions

73
Some Governments, Corporations, and Individuals
Are Leading the Way (2)
  • Major global companies reducing greenhouse gas
    emissions
  • Alcoa
  • DuPont
  • IBM
  • Toyota
  • GE
  • Wal-Mart
  • Fluorescent light bulbs
  • Auxiliary power units on truck fleets

74
Some Governments, Corporations, and Individuals
Are Leading the Way (3)
  • Colleges and universities reducing greenhouse gas
    emissions
  • Oberlin College, Ohio, U.S.
  • 25 Colleges in Pennsylvania, U.S.
  • Yale University, CT, U.S.
  • What is your carbon footprint?
  • What can you do?

75
We Can Prepare for Global Warming (1)
  • Reduce greenhouse gas emissions as much as
    possible
  • Move people from low-lying coastal areas
  • Limit coastal building
  • Remove hazardous material storage tanks away from
    the coast

76
We Can Prepare for Global Warming (2)
  • Genetically engineer crops more tolerant to
    drought
  • Stockpile 15 years of key foods
  • Waste less water
  • Connect wildlife reserves with corridors

77
12-8 How Have We Depleted Ozone in the
Stratosphere and What Can We Do?
  • Concept 12-8A Widespread use of certain
    chemicals has reduced ozone levels in the
    stratosphere, which has allowed more harmful
    ultraviolet radiation to reach the earths
    surface.
  • Concept 12-8B To reverse ozone depletion, we
    must stop producing ozone-depleting chemicals,
    and adhere to the international treaties that ban
    such chemicals.

78
Human Activities Threaten the Ozone Layer
  • Ozone Thinning
  • Seasonal depletion in the stratosphere
  • Antarctica and Arctic
  • 1930 Midgely
  • Discovered the first CFC
  • 1984 Rowland and Molina
  • CFCs were depleting O3
  • Other ozone-depleting chemicals

79
Science Focus Rowland and MolineA Scientific
Story of Courage and Persistence
  • Research
  • CFCs are persistent in the atmosphere
  • Rise into the stratosphere over 11-20 years
  • Break down under high-energy UV radiation
  • Halogens produced accelerate the breakdown of O3
    to O2
  • Each CFC molecule can last 65-385 years
  • 1988 Dupont stopped producing CFCs
  • 1995 Nobel Prize in chemistry

80
We Can Reverse Stratospheric Ozone Depletion (1)
  • Stop producing all ozone-depleting chemicals
  • 60100 years of recovery of the O3 layer
  • 1987 Montreal Protocol
  • 1992 Copenhagen Protocol
  • Ozone protocols prevention is the key

81
We Can Reverse Stratospheric Ozone Depletion (2)
  • Substitutes for CFCs are available
  • More are being developed
  • HCFC-22
  • Substitute chemical
  • May still be causing ozone depletion

82
Ozone Levels over the Earths Poles Drop for a
Few Months Each Year
  • Seasonal fluctuations
  • Antarctic
  • Arctic

83
Why Should We Worry about Ozone Depletion?
  • Damaging UV-A and UV-B radiation
  • Increase eye cataracts and skin cancer
  • Impair or destroy phytoplankton
  • Significance?

84
Science Focus Skin Cancer
  • UV-B ionizing radiation
  • Risk factors
  • Children and adolescents
  • Blistering sunburns
  • Caucasians
  • Tanning parlors
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