Air and Air Pollution

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Air and Air Pollution
Living in the Environment Chapter 17 Sections 4-6
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Key Concepts

• Structure and composition of the atmosphere

• Types and sources of outdoor air pollution

• Types, formation, and effects of smog

• Sources and effects of acid deposition

• Effects of air pollution

• Prevention and control of air pollution

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ACID DEPOSITION
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Acids

• Release hydrogen ions in solution
• pH less than 7
• pH is tenfold
• pH directly related to H ions
• Rain pH 5.6 due to CO2
• What are examples produced in environment?

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Acid Deposition

• What do smokestacks emit?
• What effect do tall smokestacks have on the
  environment?
• What secondary pollutants are produced from
  emissions?

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Acid Deposition

• What do smokestacks emit? Smokestacks emit SO2
  and NOx
• What effect do tall smokestacks have on the
  environment? Reduce local air pollution but
  increase regional air pollution. Blame Canada!
• What secondary pollutants are produced from
  emissions?
• Nitric Sulfuric acids salts

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Acid Deposition Acid Rain
Acid deposition
Wet deposition Rain, snow, fog
Dry deposition particles
Fig. 17.9, p. 428
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Acid Deposition in the US
Coal Burning Industrial Emissions
pH 2.3 on mountain tops!
Fig. 17.10, p. 428
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From western Europe
From Ohio Valley
From China
From Canada
Potential problem areas because of sensitive soils
No natural buffers
Potential problem areas because of air
pollution emissions leading to acid deposition
Current problem areas (including lakes and rivers)
Fig. 17.11, p. 429
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China
Iran
Pakistan
Saudi Arabia
India
Myanmar
Arabian Sea
Thailand
Bay of Bengal
Ethiopia
Indian Ocean
Equator
Winter monsoon blows out and Spring monsoons
blows back
Percentage of direct sunlight intercepted
Very heavy 3545
Heavy 2035
Medium 1020
Fig. 17.12a, p. 429
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Acid Deposition and Humans

• Respiratory diseases

• Toxic metal leaching into drinking water

• Decreased visibility from sulfate particles

• Damage to structures, especially containing
  limestone

• Decreased productivity and profitability of
  fisheries, forests, and farms

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Acid Deposition and Aquatic Ecology

• Normal pH is between 6-8

• pH 6

• Undesirable plankton and mosses
• Fish populations decrease

• pH 5

• Fish populations disappear
• Decay at bottom
• Mosses may dominate nearshore

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Acid Deposition and Aquatic Ecology

• pH 4.5

• No fish

• Other effects

• Al leachate fish cant breathe
• Toxic, fatty soluble Hg magnified
• Acid shock from runoff
• Lose buffering ability

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Acid Deposition and Aquatic Systems

• Fish declines

• Undesirable species

• Aluminum toxicity

• Acid shock

Fig. 17.13, p. 430
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Acid Deposition on Plants Soil

• Harm to forests and crops begins at pH 5.1

• Direct

• Damaged waxy surface
• Impaired germination

• Indirect

• Essential plant salts leach
• Al3 prevents uptake of nutrients and water
• Toxic heavy metals
• Acid loving mosses hold water, remove air, kill
  fungi
• Weaken trees

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• Weakens trees

• Fig. 17.14, p. 432
• See Connections p. 431

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Whats being done?

• NAPAP National Acid Precipitation Assessment
  Program

• Bad News
• adverse impact on forest ecosystems and waiting
  for effects on others
• tenfold increase in acidity in first 36 cm of
  soil
• Nitrate concentrations in atmosphere have not
  decreases
• No decline in acidity in sensitive aquatic
  systems

• Good news
• Reductions in SO2 and NOx emissions
• Declines in acidity in midwest and northeast
• Sulfate concentrations have dropped in lakes
• SO2 and NOx and particulate matter decreases may
  increase health
• SO2 reduction benefits exceed costs

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Whats can be done to reduce Acid Deposition?

• Energy Efficiency
• Coal Use
• Natural Gas
• Renewable resources
• Low sulfur coal
• Smokestacks
• Motor vehicle exhaust
• Taxes
• Liming and phosphates

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Solutions Preventing and Reducing Air Pollution

• Clean Air Act

• National Ambient Air Quality Standards (NAAQS)

• Primary and secondary standards

• Output control vs. input control

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Emission Reduction
Fig. 17.21, p. 442
Fig. 17.22, p. 442
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Most dangerous are
Fig. 17.16, p. 435
Pb Cd 60 higher
Carcinogenic
Pesticides
Up to 5x higher indoors
Pollution in your car
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Radon

• Radon-222 is naturally occuring

• Seeps upward and disperses

• Gets concentrated in houses

• Alpha Particles damage tissue

• Expensive to test

Fig. 17.17, p. 436
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Reducing IndoorAir Pollution
See www.epa.gov/iaq/
Fig. 17.24, p. 443