1. 12-01
Title:
The Atmosphere
Caption:
Diagram showing where each layer of the atmosphere is found.
Notes:
The ozone layer is in the stratosphere.

2. 12-02
Title:
The Nitrogen Cycle
Caption:
Fixation of nitrogen and its release back into the atmosphere.
Notes:
Plant and animal matter decay to replenish the nitrogen in the atmosphere.

3. 12-03
Title:
The Oxygen Cycle
Caption:
The fixation of oxygen and its release back into the atmosphere.
Notes:
Oxygen is converted to ozone in the stratosphere.

4. 12-04a,b
Title:
Temperature Inversion
Caption:
Normal air temperature pattern (a) and a temperature inversion pattern (b).
Notes:
Air tends to get colder as the altitude increases.

5. 12-05B
Title:
Smokestack Treatment
Caption:
One of the methods used to decrease air pollution caused by particulates in smokestacks.
Notes:
Air pollution is a major concern in our society.

6. 12-05C
Title:
Electrostatic Precipitator
Caption:
One of the methods used to decrease air pollution caused by particulates in smokestacks.
Notes:
Air pollution impacts the economy.

7. UN
Title:
Sources of Carbon Monoxide
Caption:
Pie chart showing the sources of carbon monoxide pollution.
Notes:
Transportation is the major contributor to CO pollution.

8. 12-06
Title:
CO and Hemoglobin
Caption:
Binding of carbon monoxide to iron in hemoglobin.
Notes:
Note that CO binds more strongly to hemoglobin than does oxygen.

9. 12-08
Title:
Air Pollution
Caption:
Graph showing air pollutant concentrations at different times of the day.
Notes:
Ozone pollution occurs later in the day.

10. 12-09
Title:
Acid Rain pH
Caption:
The position of acid rain on the pH scale.
Notes:
Acid rain has a pH below 5.6.

11. 12-10
Title:
Acid Rain
Caption:
Diagram illustrating the production of acid rain from human sources.
Notes:
Oxides of S and N are further oxidized.

12. 12-12
Title:
The Greenhouse Effect
Caption:
Diagram illustrating how the greenhouse effect occurs.
Notes:
Molecules absorb infrared energy.

13. 12-13
Title:
Global Warming
Caption:
Graph showing the increase in carbon dioxide concentrations over the past millennium.
Notes:
There has been a dramatic increase in carbon dioxide concentration during the 1900s.

14. 12-14
Title:
Average Surface Temperature
Caption:
Graph showing the changes in average surface temperature by year.
Notes:
A global warming effect can be seen after 1980.

15. UN
Title:
Global Warming Project
Caption:
Graph for the Web Investigation on global warming.
Notes:
temperature changes during the past and next millennia

16. 12-TB01
Title:
Table Clean Dry Air Composition
Caption:
Composition of clean air near sea level.
Notes:
Air is mostly nitrogen and oxygen.

17. 12-TB02
Title:
Table Ozone Pollution
Caption:
Metropolitan areas ranked according to ozone pollution.
Notes:
Los Angeles leads all other cities in ozone pollution.

18. 12-TB03
Title:
Table Air Quality Standards
Caption:
Pollution limits established for seven air pollutants.
Notes:
ppm = parts per million

19. 12-TB04
Title:
Table Seven Major Air Pollutants
Caption:
Sources and effects of seven major air pollutants.
Notes:
Most pollutants are small inorganic molecules.