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Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
Heat Transfer ReadingHeat is the movement of energy of from one place to another. Heat moves from hotter to cooler objects. If you were to step barefooted onto a tile floor it might feel cold. You may think the cold is moving into your foot. What really happens is heat is moving from your foot to the floor. This is why your foot feels colder.
Heat can move from one object to another in three ways…conduction.convection.radiation.
Conduction Conduction happens when heat moves from one object to another by direct contact. Think of a time you have burned your hand by touching a hot spoon in a bowl of hot soup. The hot water transfers its heat through molecules bumping into each other. This continues until the spoon and soup are the same temperature.For there to be heat transfer through conduction, you must have a conductor. A conductor is something through which heat moves. Metals are excellent conductors of heat. Convection Convection is the rising of the hot and falling of the cold. Convection occurs only in liquids and gases. It also requires a medium. That medium is always a liquid or gas.
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Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
Density affects convection. Hot air rises because it is less dense. When a liquid or a gas is heated, are heated, their molecules begin to move faster, bounce off each other, and move farther apart.Remember, all matter is made of tiny particles called atoms or molecules. These tiny particles are always in motion – either bumping into each other or vibrating back and forth.When heat is added to a substance, the particles begin to move faster. They begin to move farther apart. They collide into other particles. As the particles move farther apart, the substance becomes less dense. The diagrams show what happens to water particles as the water is heated.
As the water is heated, the particles move farther apart. As the particles move farther apart, the water becomes less dense. If you place hot water in cold water, the hot water will rise to the top. This is because hot water is less dense than cold water. Most energy is moved through Earth’s systems by convection. Convection occurs in water and air. Uneven heating of matter drives convection. Most matter becomes less dense when heated. Hotter, less dense matter rises through surrounding matter. As the hot matter rises, it cools and becomes more dense. As a result, this matter sinks back, this matter sinks back toward the heat source where it is warmed again. This movement of matter which results from differences in density is called a convection current.
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Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
Convection in the OceanConvection currents occur in the ocean because of differences in the density of ocean water. The uneven heating of ocean water causes these differences. The differences in density are also caused by differences in the salinity of ocean water. Salinity is the amount of salt in water. In the ocean, convection causes deep currents. Deep currents are streamlike movements of water far below the ocean surface. As the diagram below shows, deep currents flow from the North Atlantic Ocean to Antarctica. Then, they flow around Antarctica and into the Pacific Ocean. The cold bottom water then flows northward toward Alaska. This journey takes more than 1,000 years.
Convection in ocean currents occur in steps. As water travels towards the poles, it gets colder. Water
becomes more concentrated with salt as surface water evaporates and sea ice forms (sea ice rejects salt during formation).
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Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
Cooling and increased salt concentration causes water at the poles to be more dense, sinking towards the ocean floor.
Warm water from the equator replaces the cooled water; the cycle then repeats
Heat transfer in the ocean causes water currents. This movement of water that this heat transfer causes affects other Earth systems as well, like the formation of sea ice that contributes to the water freezing over in areas near the poles.Convection in the atmosphereThe process of convection in the atmosphere is shown in the figure to the left. If Earth’s surface is warmer than the air, conduction will heat the air touching the ground. As this are becomes warmer, it becomes less dense and rises. The warm air moves upward, away from the Earth’s surface. As the air rises, it cools. The air becomes more dense and begins to sink back toward Earth’s surface. As the cooled air sinks, it forces warm air away from Earth’s surface. This cycle causes winds and moves energy through the atmosphere.
This process happens in steps. Near the equator, solar radiation
hits the earth at the highest levels. Solar radiation affects the air
around the equator, which heats up rapidly and becomes less dense.
Colder, more dense air from above displaces the warm, less dense air into the atmosphere.
Warm air then spreads out towards the poles and cools.
The now-cooled air sinks back down and creates a high pressured area.
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Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
High pressured cool air pushes more low density warm air into the atmosphere, and the cycle repeats indefinitely.
Heat transfer in the atmosphere is what creates air currents. Air usually flows from areas of high pressure to low pressure, which is what causes air current (commonly known as wind). Because of the permanent bands of high/low pressure, there are air currents called prevailing winds that flow nearly always. Due to the rotation of Earth, prevailing winds curve around Earth instead of going straight north to south and vice versa. These air currents can affect and influence ocean currents (e.g. Gulf Stream)
Name ______________________________________________________________
Heat Transfer Reading1. Heat is the movement of energy of from one place to another.
a. True b. False2. Heat moves from ________ to ________ objects.
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Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
a. cooler/hotter b. hotter/cooler3. Which is a form of heat transfer.
a. Conduction c. Radiationb. Convection d. All of the above
4. Conduction happens when heat moves from one object to another…
a. by direct contact. c. when hot rises and cold falls.
b. through an electromagnetic wave.5. When a metal spoon is placed in a hot bowl of soup, the heat in the spoon continues until the spoon and soup are the same temperature.
a. True b. False6. Metals are a poor conductor of heat.
a. True b. False7. This form of heat transfer is the rising of the hot and the falling of the cold.
a. Conduction c. Radiationb. Convection
8. Convection only occurs in solids.a. True b. False
9. An example of a medium is…a. Gas c. Both a & bb. Liquid
10. Hot air rises because it is…a. less dense. b. more dense.
Use the diagram to answer question #11.
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Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
A B
11. Which diagram shows heated air?a. A b. B
12. When heat is added to a substance, the particles begin to move_____ and move ______ apart. They begin to move farther apart. They collide into other particles. As the particles move farther apart, the substance becomes less dense.
a. faster/farther apart c. Faster/closer togetherb. slower/farther apart d. slower/closer
together13. If you place hot water in cold water, the hot water will…
a. sink to the bottom. c. rise to the top.14. Most energy is moved through Earth’s systems by…
a. conduction. c. radiation.b. convection.
15. As the hot matter rises, it cools. As it cools, it sinks back toward the heat source where it is warmed again. This movement of matter is called a…
a. conduction current. c. radiation current.b. convection current.
16. In the ocean, convection currents happen because of the different is the density of the ocean water.
a. True b. False
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Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
17. Difference is ocean water density is caused by…a. even heating of the ocean water. b. uneven heating of
the ocean water.18. Salinity is the amount of salt in water.
a. True b. False19. In the ocean convection causes…
a. deep currents. b. surface currents.20. Deep currents flow from the North Atlantic Ocean to Antarctica. Then, they flow around Antarctica and into the Pacific Ocean. The cold bottom water then flows northward toward Alaska. This journey takes more than ___________ years. (Enter a number)21. Movement of water that heat transfer causes affects other Earth systems.
a. True b. False22. If Earth’s surface is warmer than the air, ________________ will heat the air touching the ground.
a. conduction c. radiationb. convection
23. As this air becomes warmer, the air begins to…a. fall. b. rise.
24. As the warm air cools, it begins to…a. fall. b. rise.
Place the steps of air movement in the proper order.
_____25. Step 1_____26. Step 2
A. Colder, more dense air from above displaces the warm, less dense air into the atmosphere.B. High pressured cool air pushes more low density warm air into the atmosphere, and the
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Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
_____27. Step 3_____28. Step 4_____29. Step 5_____30. Step 6
cycle repeats indefinitely.C. Near the equator, solar radiation hits the earth at the highest levels.D. Solar radiation affects the air around the equator, which heats up rapidly and becomes less dense.E. The now-cooled air sinks back down and creates a high pressured area.F. Warm air then spreads out towards the poles and cools.
31. Near the equator, solar radiation hits the earth at the ______ levels.
a. highest b. lowest32. As Air flows from areas of high pressure to low pressure it forms…
a. clam weather. c. snow.b. rain. d. wind.
33. Due to the rotation of Earth, prevailing winds curve around Earth instead of going straight north to south and vice versa.
a. True b. False
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Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
Heat Transfer Reading – Key 1. Heat is the movement of energy of from one place to another.
a. True b. False
a. True
2. Heat moves from ________ to ________ objects.
a. cooler/hotter b. hotter/cooler
b. hotter/cooler
3. Which is a form of heat transfer.10
Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
a. Conduction c. Radiationb. Convection d. All of the above
d. All of the above
4. Conduction happens when heat moves from one object to another…
a. by direct contact. c. when hot rises and cold falls.
b. through an electromagnetic wave.
a. by direct contact.
5. When a metal spoon is placed in a hot bowl of soup, the heat in the spoon continues until the spoon and soup are the same temperature.
a. True b. False
a. True
6. Metals are a poor conductor of heat.
a. True b. False
b. False
7. This form of heat transfer is the rising of the hot and the falling of the cold.
a. Conduction c. Radiationb. Convection
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Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
b. Convection
8. Convection only occurs in solids.
a. True b. False
b. False
9. An example of a medium is…
a. Gas c. Both a & bb. Liquid
c. Both a & b
10. Hot air rises because it is…
a. less dense. b. more dense.
a. less dense
Use the diagram to answer question #11.
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Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
A B
11. Which diagram shows heated air?
a. A b. B
b. B
12. When heat is added to a substance, the particles begin to move_____ and move ______ apart. They begin to move farther apart. They collide into other particles. As the particles move farther apart, the substance becomes less dense.
a. faster/farther apart c. Faster/closer togetherb. slower/farther apart d. slower/closer
together
a. faster/farther apart
13. If you place hot water in cold water, the hot water will…
a. sink to the bottom. c. rise to the top.
b. rise to the top.
14. Most energy is moved through Earth’s systems by…
a. conduction. c. radiation.
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Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
b. convection.
b. convection.15. As the hot matter rises, it cools. As it cools, it sinks back toward the heat source where it is warmed again. This movement of matter is called a…
a. conduction current. c. radiation current.b. convection current.
b. convection current.
16. In the ocean, convection currents happen because of the different is the density of the ocean water.
a. True b. False
a. True
17. Difference is ocean water density is caused by…
a. even heating of the ocean water. b. uneven heating of the ocean water.
b. uneven heating of the ocean water.
18. Salinity is the amount of salt in water.
a. True b. False
a. True
19. In the ocean convection causes…
a. deep currents. b. surface currents.14
Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
a. deep currents.
20. Deep currents flow from the North Atlantic Ocean to Antarctica. Then, they flow around Antarctica and into the Pacific Ocean. The cold bottom water then flows northward toward Alaska. This journey takes more than ___________ years. (Enter a number)
1,000
21. Movement of water that heat transfer causes affects other Earth systems.
a. True b. False
a. True
22. If Earth’s surface is warmer than the air, ________________ will heat the air touching the ground.
a. conduction c. radiationb. convection
a. conduction
23. As this air becomes warmer, the air begins to…
a. fall. b. rise.
b. rise.15
Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
24. As the warm air cools, it begins to…
a. fall. b. rise.
a. fall.
Place the steps of air movement in the proper order._____25. Step 1_____26. Step 2_____27. Step 3_____28. Step 4_____29. Step 5_____30. Step 6
A. Colder, more dense air from above displaces the warm, less dense air into the atmosphere.B. High pressured cool air pushes more low density warm air into the atmosphere, and the cycle repeats indefinitely.C. Near the equator, solar radiation hits the earth at the highest levels.D. Solar radiation affects the air around the equator, which heats up rapidly and becomes less dense.E. The now-cooled air sinks back down and creates a high pressured area.F. Warm air then spreads out towards the poles and cools.
C 25. Step 1D 26. Step 2A 27. Step 3F 28. Step 4E 29. Step 5B 30. Step 6
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Learning Target – I can model unequal heating on Earth causes atmosphere and ocean circulation.
31. Near the equator, solar radiation hits the earth at the ______ levels.
a. highest b. lowest
a. highest
32. As Air flows from areas of high pressure to low pressure it forms…
a. clam weather. c. snow.b. rain. d. wind.
d. wind.
33. Due to the rotation of Earth, prevailing winds curve around Earth instead of going straight north to south and vice versa.
a. True b. False
a. True
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