Air Pollution (continued)

Chapter 18 AhrensMonday, 30 November

Class #37

1Monday, November 30

Review sheet for test #5

• Ahrens– Chapter 2, pages 34-41– Chapter 3, pages 66-70 and 78-82– Chapter 4, pages 103-105– Chapter 18, pages 502-525

Monday, November 30 2

Primary and secondary pollutants

• Primary air pollutants enter the atmosphere directly from their sources– Examples are carbon monoxide and sulfur dioxide

• Secondary air pollutants form only when a chemical reaction occurs with primary air pollutants– Examples are photochemical oxidants and acid

deposition– Secondary air pollutants are more difficult to control

Monday, November 30 3

Santiago, Chile

Monday, November 30 4Fig. 18-CO, p. 500

Table 18-1, p. 5035Monday, November 30

Fig. 18-3a, p. 5046Monday, November 30

Fig. 18-3b, p. 5047Monday, November 30

Table 18-2, p. 5138Monday, November 30

Fig. 18-10, p. 5129Monday, November 30

Stepped Art

Fig. 18-10, p. 51210Monday, November 30

Table 18-3, p. 51311Monday, November 30

Fig. 18-11, p. 51412Monday, November 30

Fig. 18-12, p. 51413Monday, November 30

A secondary pollutant: smog/photochemical oxidants/ozone• Smog originally meant smoke and fog• Now smog refers to the chemical soup created

by sunlight acting on hydrocarbons (VOCs) and oxides of nitrogen in the presence of oxygen and sunlight

• Ozone is the main constituent of smog, but there are many others, including PAN

• Smog attacks the respiratory system

Monday, November 30 14

Fig. 18-6, p. 50715Monday, November 30

Secondary air pollutant: acid deposition

• Acid deposition: can be dry or acid rain, snow, fog, dew– Oxides of sulfur, oxides of nitrogen combine with

water vapor or liquid water drops in the air– Sulfuric acid, nitric acid form– Acid attacks structures and plants– In bodies of water, acid allows heavy metals to

leach out and contaminate water supplies, toxify water for fish and other living things

Monday, November 30 16

Fig. 18-21, p. 52417Monday, November 30

Fig. 18-22, p. 52418Monday, November 30

Fig. 18-23, p. 52519Monday, November 30

Fig. 18-13, p. 51520Monday, November 30

Fig. 18-14, p. 51721Monday, November 30

Fig. 18-14a, p. 51722Monday, November 30

Fig. 18-14b, p. 51723Monday, November 30

Fig. 18-15, p. 51724Monday, November 30

Fig. 4, p. 51825Monday, November 30

Fig. 4a, p. 51826Monday, November 30

Fig. 4b, p. 51827Monday, November 30

Fig. 4c, p. 51828Monday, November 30

Fig. 4d, p. 51829Monday, November 30

Fig. 4e, p. 51830Monday, November 30

Fig. 18-16, p. 51931Monday, November 30

Fig. 18-17, p. 51932Monday, November 30

Fig. 18-18, p. 52033Monday, November 30

Stepped Art

Fig. 18-18, p. 52034Monday, November 30

Fig. 18-19, p. 52035Monday, November 30

Fig. 5, p. 52136Monday, November 30

Ingredients for an episode of air pollution

• Many sources of air pollution close together• A deep stationary high-pressure area• Light surface winds that limit dispersion• A strong subsidence inversion• A shallow mixing layer with poor ventilation• A valley where pollutants can accumulate• Clear skies, radiational cooling at night, and a

surface inversionMonday, November 30 37

Table 18-4, p. 52238Monday, November 30

Fig. 18-20, p. 52339Monday, November 30