Explain why skylight is typically blue when the air is “clean” or has a low concentration

1. The dominant type of radiation energy emitted from the surface of the sun is classified

as what type of radiation (e.g., microwave, infrared, visible, ultraviolet, X-ray)? The

dominant type of radiation energy emitted from the surface of the Earth is classified as

what type of radiation?

2. In your own words, describe what it means for a planet to be in “radiative equilibrium.”

3. Answer the following questions:

 Write down the six greenhouse gases that were targeted for reduction in the first

Kyoto Protocol of 1997.

 The original Kyoto Protocol expired in 2012. Is there a new international agreement

to further reduce greenhouse gas emissions?

 What are some reasons why the United States did not agree to either the original or

the updated Kyoto Protocol?

 Which two countries that signed the original Kyoto Protocol did not agree to any

further emission reductions?

4. What is meant by Global Warming Potential (GWP)? Which greenhouse gas has the

lowest GWP?

5. Describe the “missing sink” problem for atmospheric carbon dioxide.

6. As part of the carbon cycle, the ocean surface waters contain a reservoir of carbon in the

form of dissolved carbon dioxide. Carbon is exchanged between the atmosphere and the

ocean surface waters. The amount of dissolved carbon dioxide that the ocean waters will

hold depends on two variables as follows: (a) the higher the concentration of carbon

dioxide in the atmosphere, the more carbon dioxide that will be dissolved in the ocean and

(b) the higher the temperature of the ocean water, the less carbon dioxide that will be

dissolved in the ocean.

State and briefly explain whether the processes (a) and (b) described above will be

positive or negative feedbacks with respect to possible global warming caused by

human burning of fossil fuel. You should discuss each feedback process individually.

In reality both of these feedbacks operate together.

7. Answer the following questions:

 What is the current trend for Arctic sea ice cover in the summer season, i.e., is the

total area covered by sea ice increasing or decreasing with time?

 What is the current trend for Antarctic sea ice cover?

 Do either of these trends provide good evidence that human activity is responsible

for the changes in sea ice area? Explain.

8. When someone is asked why there are seasons on Earth a common memorized answer

is “because the Earth is tilted on its axis.”

What is the axis that is being referred to?

What does it mean to say this axis is “tilted”, i.e., tilted relative to what?

What is the “tilt” angle for Earth?

Suppose this angle were 0° (no tilt), would there still be seasonal changes, i.e., distinct

summers and winters on Earth? Briefly explain your answer.

9. Explain why skylight is typically blue when the air is “clean” or has a low concentration

of aerosols but becomes more whitish looking when the air is “dirty” or has a high

concentration of aerosols.

10. The daily temperature spread is defined as the difference between the high temperature

and the low temperature. Compared with most cities, does Tucson have a relatively large

daily temperature spread or a relatively small daily temperature spread? Give at least three

reasons for your answer along with a brief explanation for each. There are more than three

valid reasons.