1. Read each slide, some slides have information to record on your organizer. Some slides have numbers that go with the question or red and underlined to use for answering the questions.

2. Essential Question:
How does unequal heating and the Earth’s rotation affect wind & weather patterns?
Standards:
S6E4a. Demonstrate that land and water absorb and lose heat at different rates and explain the resulting effects on weather patterns.
S6E4b. Relate unequal heating of land and water surfaces to form large global wind systems…
S6E2c. Relate the tilt of the earth to the distribution of sunlight throughout the year and its effect on climate.

3. Learning Target:
When the temperature of a fluid (like air) changes, so does its density.  As the density of air changes, it begins to move  - cooler, more dense air sinks and warmer, less dense air rises.  So differences in the temperature of air in the atmosphere sets air in motion, which drives all of the weather on Earth.  To truly understand this, we need to step back and explore why and where on earth there are temperature differences.

4. Objectives
Explain how the sun heats Earth's surface unevenly. Describe global patterns of wind, precipitation, and ocean currents.

5. Read ONLY!
Uneven Heating of Earth's Surface Energy from the sun warms Earth's surface. But because of Earth's spherical shape, different locations on Earth's surface receive different amounts of solar energy. Near the equator, the sun's rays strike the surface most directly. At latitudes farther from the equator the rays strike Earth's surface at lower angles, causing the same amount of solar energy to be spread over a larger area (Figure 34-6). As a result, regions on Earth's surface farther from the equator absorb less heat and generally experience cooler temperatures than regions closer to the equator. These temperature differences also drive global air and water movements.

6. 1. Read then summarize use the red to help you in the summary!
The uneven heating of the Earth's surface is caused by the sun. This occurs because the Earth is a tilted sphere and the sun does not heat all its surfaces equally and because the sun's heat penetrates land and water at different rates.

7. 2. This uneven heating of land forms wind systems.
(Figure 34-6).

8. Air pressure is related to density. Let’s review density.
3. Wind is caused by differences in air pressure. Areas of high pressure move to areas of low pressure.
Air pressure is related to density. Let’s review density.
Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes.

9. Which one has greater density? Greater pressure?
Lower Density
Lower Pressure

10. We will consider Density and Pressure to be the same.
What about temperature? What did you learn about temperature and density?

11. Look at the images below
Look at the images below. Identify which image has: Higher Temperature, Higher Density, Higher Pressure.
Higher Temperature
Lower Temperature
Higher Density
Lower Density
Lower Pressure
Higher Pressure

12. 4.Temperature, Density and Pressure
Density increases,
Pressure increases
Temperature increases
Temperature decreases
Density decreases,
Pressure decreases

13. Let’s apply these concepts back to wind.
Wind is caused by differences in air pressure. Areas of high pressure move to areas of low pressure.

14. In which direction would the wind move below.
Higher Temperature
Lower Density
Lower Pressure
Lower Temperature
Higher Density
Higher Pressure

15. Why? Higher Temperature Lower Temperature Higher Density Lower Density
Lower Pressure
Lower Temperature
Higher Density
Higher Pressure

16. Think of it this way…matter naturally wants to move from where it is crowded to where it is less crowded. This concept is true for all of science.
Higher Temperature
Lower Density
Lower Pressure
Lower Temperature
Higher Density
Higher Pressure

17. Particles naturally want to move from where they are more crowded to where they are less crowded.

18. 5. Which areas of the earth have air that is low pressure (low density)? Why? What about high pressure (high density)?

19. Distributed Summarizing:
Turn to a seat partner and describe how wind moves. Together discuss the following question: What makes wind travel at faster speeds?

20. 8. Differences in density and pressure cause wind and air movement
8. Differences in density and pressure cause wind and air movement. The movement of air occurs in convection currents.
Convection currents are simply the transfer of heat by the circulation or movement of the heated parts of a liquid or gas.

21. 10. Everyday Examples of Convection Currents.

22. 12.
Large Convection Currents are formed because of the temperature differences between the equator and the poles. This produces global wind systems.

23. The sinking of cold, dense air and the rising of warm, less dense air do not explain everything about wind. What other factor have we discussed previously that affects the direction of winds on the earth’s surface? .

24. Surface winds and surface currents are affected by the rotation of the Earth (the Coriolis Effect) Because Earth rotates toward the east, winds appear to curve to the right in the northern hemisphere and to the left in the southern hemisphere

25. The effect of the earth’s rotation (Coriolis Effect) on Winds

26. The flow of air caused by unequal heating of the Earth’s surface and the rotation of the Earth (Coriolis Effect) creates distinct wind patterns on Earth’s surface.
These wind systems not only influence the weather, they also determine when and where ships and planes travel most efficiently.

27. Below is a diagram showing the global wind patterns that distribute heat and moisture around the globe. Use with question 15

28. Instructional Approach(s): The teacher should use the image on the diagram to illustrate the direction of winds.

29. What are the global wind patterns
What are the global wind patterns? The equator receives the Sun's direct rays. Here, air is heated and rises, leaving low pressure areas behind. Moving to about thirty degrees north and south of the equator, the warm air from the equator begins to cool and sink. Between thirty degrees latitude and the equator, most of the cooling sinking air moves back to the equator. The rest of the air flows toward the poles.

30. Distributed Summarizing:
Turn to a seat partner and describe the factors that influence global wind patterns.
Instructional Approach(s): Have students turn to a partner and discuss the question on the slide. Partners can be determined by the students or the teacher can provide more specific directions such as turn to the person directly in front/behind you or to the right/left of you, etc. It may be necessary to have a group of three if you have an uneven number of students. Do not allow more than 30 seconds to 1 minute of discussion time. The teacher should be walking around listening and redirecting discussions as needed. The teacher can briefly discuss student responses.

31. Global wind systems determine the major weather patterns for the entire planet.
Smaller wind systems affect local weather. Two such wind systems are sea breezes and land breezes.
Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes.

32. High 65°F Pressure 85°F Low Pressure
Instructional Approach(s): The teacher should present the information on the slide. The teacher can call on students to respond or ask for student responses. When ready, click the mouse to reveal the answers.
Look at the temperatures of the land and the sea in this diagram. Which direction would the wind blow? Why?

33. A sea breeze occurs when wind is moving from the sea towards land.
High
Pressure
65°F
85°F
Low Pressure
Instructional Approach(s): The teacher should present the information on the slide.
A sea breeze occurs when wind is moving from the sea towards land.

34. Land heats up and cools down faster than water
Land heats up and cools down faster than water. How does this affect wind?
Instructional Approach(s): The teacher should present the information on the slide.

35. Low Pressure 65°F 55°F High Pressure
At night when the earth’s surface is no longer being heated by the sun, the land cools much more rapidly than ocean water. What happens to the wind?
Instructional Approach(s): The teacher should present the information on the slide. The teacher can call on students to respond or ask for student responses. When ready, click the mouse to reveal the answers.

36. A land breeze occurs when wind is moving from the land to the sea.
Low
Pressure
65°F
55°F
High Pressure
Instructional Approach(s): The teacher should present the information on the slide.
A land breeze occurs when wind is moving from the land to the sea.

37. How do sea breezes and land breezes affect local weather?
Instructional Approach(s): The teacher should present the information on the slide.

38. Local winds: Sea Breeze and Land Breeze

39. What is a High Pressure System?
A high pressure system is a whirling mass of cool, dry air that generally brings fair weather and light winds. When viewed from above, winds spiral out of a high-pressure center in a clockwise rotation in the Northern Hemisphere. These bring sunny skies. A high pressure system is represented as a big, blue H. H

40. What is a Low Pressure System?
A low pressure system is a whirling mass of warm, moist air that generally brings stormy weather with strong winds. When viewed from above, winds spiral into a low-pressure center in a counterclockwise rotation in the Northern Hemisphere. A low pressure system is represented as a big, red L L

41. Sea
Breeze
Land
Breeze

42. Identify which diagram illustrates a Sea Breeze and a Land Breeze
Identify which diagram illustrates a Sea Breeze and a Land Breeze. Explain why. Include high and low air pressure in your explanation.
Instructional Approach(s): The teacher can have students answer the questions individually or with a partner.

43. A land breeze is a local nighttime and early morning wind that occurs along coasts and blows offshore (from the land out to sea). It arises at sunset, when the sea surface is warmer than the adjacent land due to the land cooling off faster and having a lower heat capacity, and continues into the early morning hours until the heating of the day begins.
Although commonly associated with ocean shorelines, land breezes can also be experienced near lakes and other large bodies of water.
Sea Breeze
High Pressure
Low Pressure
Sea breeze, a local wind system characterized by a flow from sea to land during the day. Sea breezes alternate with land breezes along the coastal regions of oceans or large lakes in the absence of a strong large-scale wind system during periods of strong daytime heating
Low Pressure
Land Breeze
High Pressure

44. Summary: