Air Quality Issues

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Air Quality Issues I

• Chapter 17
• The atmosphere, pollution, and pollution control

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Outline

• The atmosphere
• Types of air pollution
• Acid deposition
• Ozone depletion
• Control of air pollution and Solutions
• Next Lecture global warming and climate change

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The Atmosphere

• Composition
• Nitrogen 78.1 , Oxygen 20.9 , Others 1
• Atmospheric layers ( pg 387)

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17.1
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The Atmosphere

• Composition
• Nitrogen 78.1 , Oxygen 20.9 , Others 1
• Atmospheric layers ( pg 387)
• Ozone layer within stratosphere
• Absorbs UV rays
• Atmospheric air circulation due to heat and
  Coriolis effect

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• Vertical movement
• Coriolis effect
• Clockwise in North
• Counter clockwise in South

17.2
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Accumulation of Pollutants
Fig. 17.3
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Pollutants

• Natural Pollutants
• Fire and volcanoes (gases and particulates)
• Organic
• Decaying plants
• Live plants
• Insects e.g. termites (methane)
• Sea spray and pollen (particulates)
• Human-caused pollutants
• Primary air pollutants (pg 388)
• Five substances that pose a health risk
• Secondary air pollutants (pg 389)
• reaction of primary pollutants and sunlight
• E.g. ozone

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The players Air pollutants

• Carbon monoxide (CO) pg 389
• Origin Organic material burned with insufficient
  Oxygen
• Source transportation (80), industry and others
  (20)
• Effects
• Decreases bloods oxygen carrying capacity
• headaches, drowsiness, blurred vision, death
• Status
• Not persistent
• Decrease in NA

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The players Air pollutants

• Volatile Organic Compounds (VOC) hydrocarbons
  pg 390
• Origin fossil fuels
• Source cars, solvents, industry
• Effects
• Secondary air pollutants -gt smog
• toxic
• Status
• Decrease in NA due to auto modifications

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The players Air pollutants

• Particulate matter - pg 390
• Origin 10 µm particles (solid and liquid)
• Source roads, agriculture, construction
• Effects Secondary pollutants, carcinogenic,
  health
• Status Decrease in NA
• See also
• Sulfur Dioxide pg 391, Nitrogen Dioxide (pg 392),
  and lead (pg 392) decline 98 in NA

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Ground-level Ozone and Photochemical Smog (393-3)
Ozone
O2
UV Rays
O
PAN
HC
HNO3
NO2
Oxygen
H2O
NO
Vehicles produce
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Thermal inversion
Fig. 17.10

• Smog influenced by climate, traffic, and
  geographic features
• See Mexico City (pg 391)

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Acid Deposition

• Pages 398-400 ----REVIEW ON YOUR OWN

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Ozone depletion

• Pollutant in troposphere, essential in
  stratosphere blocks 99 of UV rays
• Ozone (O3) recycles itself (pg 400)
• Chlorofluorocarbons (CFC) pg 402
• Destroy stratospheric ozone
• Decreases chance of ozone reforming
• Persistant
• Ozone v. climate change
• Montreal Protocol 1987 decrease CFC emissions
  by 87
• Simple problem, one cause, easy solution

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Control of Air pollution

• Cars and other vehicles
• Fuel efficiency
• Catalytic converter
• Lead free fuel
• Particulate Matter
• Movement at global scales
• Power plants

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Improvements

• Legislation
• Air in western cities cleaner than a generation
  ago Figure 17.11 and Table 17.2
• Improved technology has compensated for more cars
  except for nitrous oxides
• Developing world?
• Slow or fast development