After the "Composition of the Atmosphere" lecture and readings you should be able to answer and discuss the following questions.

What is the atmosphere?

How does atmosphere differ from air?

What are the major components of the Earth's atmosphere in order from greatest to least amount?

Which of the major components shows the greatest amount of variation?

What is the origin of the Earth's atmosphere?

Compare and contrast the present atmosphere with the Earth's original atmosphere.

From where did the oxygen (O₂) that is currently a major component of the atmosphere come?

Where did all of the original atmospheric carbon dioxide go?

Why are these reservoirs of CO₂ important?

How have oxygen levels changed throughout the history of the Earth?

What was the percentage of oxygen believed to have been during the Pennsylvanian Period?

Why were oxygen levels this high during this period and what is the evidence that indicates higher levels of oxygen?

How are oxygen levels in the atmosphere increased?

How are oxygen levels in the atmosphere reduced?

How are carbon dioxide levels in the atmosphere increased?

How are carbon dioxide levels in the atmosphere reduced?

How are water levels in the atmosphere increased?

How are water levels in the atmosphere reduced?

How are methane levels in the atmosphere increased?

How are methane levels in the atmosphere reduced?

How are ozone levels in the atmosphere increased?

How are ozone levels in the atmosphere reduced?

Specifically how do CFCs breakdown and destroy ozone?

How are particle levels in the atmosphere increased?

How are particle levels in the atmosphere reduced?

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