Learning Exercise #5
Heat, Salinity, and Surface Circulation
A. Heat
A
B
Use the above diagram to answer the following questions. Circle the correct answer.
1. Which solar beam covers greater surface area of the Earth?
2. Which area of the Earth would be warmest?
Equator
A
or
or
B
Poles
3. Which area would the solar beam have to travel through a greater amount of atmosphere?
A
or
B
4. If the atmosphere absorbs some of the sunlight, in which area would more of the sunlight be absorbed and
therefore cooler because less light reaches the surface of the Earth?
Equator
or
Poles
5. Using your responses from above, why is it colder at the poles and warmer at the equator? (Include amount
of solar energy coming in, surface area, areas of surplus and deficit) _____________________________
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B. Heat Surplus, Deficit, and Transport
A
B
Use diagram A and B above to answer the following questions. Circle the correct answer.
1. Which area loses more heat than it gains?
0º to 30º N&S
30º to 90º N&S
2. Which area gains more heat than it loses?
0º to 30º N&S
30º to 90º N&S
3. In the area the Earth gains the most heat should evaporation exceed precipitation (E>P) Yes or No
4. In the area the Earth gains the most heat should the oceans a) evaporate away b) freeze over
5. Should the area that loses the most heat a) evaporate away
b) freeze over
6. Figure B shows that heat is transported from a) equator toward poles b) poles toward to equator
7. How is heat transported? a) ocean currents b) atmosphere c) both (a) and (b)
8. Why don’t the oceans evaporate at the equator and freeze in the polar regions? (Explain using your
responses above – heat surplus, heat deficit, transport, latitudes)
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C. Convection Cells – Non-rotating Earth
Use the above diagram to answer the following questions. Circle the correct answer.
1. When air rises, it is:
a) less dense
b) more dense
2. What happens to air at the equator?
a) rises
3. Air rises at the equator because it is
a) warm and less dense
4. Rising air is associated with:
a) high pressure areas
b) sinks
b) cold and more dense
b) low pressure areas
5. Air descends at the poles because it is
a) warm and less dense
6. Descending air is associated with:
a) low pressure
b) cold and more dense
b) high pressure
7. Air moves over the surface of the Earth from the poles to the equator because air moves from:
a) high pressure area to low pressure area
b) low pressure area to high pressure area
8. Air moving from the north pole to the equator is a(n) a) westerly b) easterly c) northerly d) southerly wind
9. Using your responses above, explain convection current. (Include warm and cool air distribution, density,
and direction of transport) ________________________________________________________________
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D. Coriolis Effect
X
A
B
Use Figures A and B to answer the following question. Circle the correct answer
1. Which city travels a greater distance around the Earth
2. Which city is moving the fastest?
a) Buffalo
a) Buffalo
b) Quito
b) Quito
3. When a cannonball is shot from Quito to Buffalo, the cannonball is traveling from an area on the globe
moving:
a) faster
b) slower
to an area moving:
4. What happened to the cannonball? It is deflected to the
5. Why was the cannonball defected?
a) faster
b) slower
a) right
b) left
a) because Quito is moving faster eastward than Buffalo
b) because Buffalo is moving faster eastward than Quito
6. A cannonball shot from Buffalo toward Quito would be defected to the
7. Why was the cannonball defected?
a) right
b) left
a) because Quito is moving slower eastward than Buffalo
b) because Buffalo is moving slower eastward than Quito
8. In the southern hemisphere, the cannonball would be deflected to the
a) left
b) right
Suppose the “X” marks the location of Santiago, Chile. (Remember you are now in the Southern Hemisphere)
9. Draw an arrow showing the path of a cannonball shot from Quito to Santiago, Chile
10. Draw an arrow showing the path of the cannonball shot from Santiago to Quito.
11. The apparent deflection of the cannonball is termed ______________________.
12. Why are winds deflected to the right in the northern hemisphere? (Include differences in speed near poles
versus equator, direction Earth is spinning) ___________________________________________________
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D. Air Circulation – Rotating Earth
A
Use the above diagram to answer the following questions. Circle the correct answer.
1. Circle areas where air is rising. A) equator b) areas marked subtropical high pressure belt c) area marked jet
stream flow d) at the pole
2. Circle areas where air is sinking. The blue arrows mark areas where the wind is moving. A) over the
Earth’s surface b) in the upper atmosphere
Focus on the air circulation cell marked “A”.
3. Air is rising at the __________________
4. What happens as air rises and moves towards to poles (blue arrow)? It is deflected to the: a) right b) left
5. Using your responses above. Explain the air circulation cells on the Earth’s surface. (Include air where
warm, less dense air rising; cool, more dense air sinking; effects of Coriolis Effect – which hemisphere
deflects air to right? to left?; direction of winds – northeasterlies, southeasterlies, etc.)
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E. Wind Patterns and Ekman Transport
A
Match the following with the appropriate letter.
B
________
Southeast tradewinds
________
Westerlies
________
Northeast tradewinds
C
A
Use the above diagram to answer the following questions. Circle the Correct answer.
The winds in the figure above will deflect the water in both the northern and southern hemisphere.
1. In the Northern Hemisphere the water will be deflected to the: a) right
b) left
2. In the Southern Hemisphere the water will be deflected to the: a) right
b) left.
3. In the figure above, draw arrows showing the deflection the water.
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Draw the arrow leading away from the arrows representing the winds.
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Draw arrows only on those wind arrows that fall over the ocean

Draw arrows for both the northern and southern hemisphere.
4. Compare your drawing with those shown in Fig 9.3 and 9.4 (page 202 in text). They should be similar.
5. Putting it All Together. Using your responses to the questions in the section on convection, the Coriolis
Effect, and surface currents, explain how the ocean surface circulation gyres develop. (Include in your
discussion how convection and the Coriolis Effect lead to the development of the global air cells; how
westerlies and the northeast and southeast trade winds develop; and how the ocean surface currents are
related to the tradewinds and the westerlies) _________________________________________________
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F. Evaporation, Precipitation, and Salinity  Density Currents
Use the above diagrams to answer the following questions. Circle the correct answer.
1. At the equator, which is greater?
a) precipitation
b) evaporation
2. At the equator, salinities are:
a) high
b) low
3. At about 10º-50º North and South latitude, which is greater?
a) evaporation
b) precipitation
4. At about 10º-50º North and South latitude, salinities are:
a) higher
b) lower
5. If evaporation exceeds precipitation, then salinities should be: a) higher
b) lower
6. If precipitation exceeds evaporation, then salinities should be: a) higher
b) lower
7. If ocean salinities increase, then density of ocean water should be: a) greater
b) less
8. Which is denser?
a) cool, salty water
b) warm, salty water
9. Which is more important in determining density of ocean waters: a) temperature
South Pole
Equator
b) salinity
North Pole
Use the diagram above and your responses to the questions #’s 1-9 (evaporation and precipitation) to explain
how density stratification develops in the oceans. (Include how evaporation and precipitation affect salinities,
how salinities affect density) _________________________________________________________________
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