1. The Atmosphere
pages

2. Lets think about it…
What is weather? What is climate? What is the difference between the two?
Weather describes what is happening in the atmosphere at a particular time and place. Climate is the general weather conditions of an area.
Areas around the world have very different temperatures. In some places, the temperature is cold throughout the year, but in other places it is hot. What causes these differences?

3. Complete the Explore on page 231.
San Francisco
Nashville

4. What are weather and climate?
Create the foldable on page 239. This will help you to follow along with the PowerPoint and take notes.
BrainPop- Weather
BrainPop- Climate
BrainPop- Earth’s Atmosphere
Weather and Climate are affected by…
Areas in the rain shadow…
El Nino causes…

5. Let’s Review What is the atmosphere?
The atmosphere is the layer of gases that surrounds the Earth.
The Earth’s atmosphere mostly consists of nitrogen and oxygen.
What are the 5 layers of gases around the Earth?
Layer closest to the Earth- troposphere, then the stratosphere, the mesosphere, thermosphere, and exosphere
Atmosphere Layer Game

6. Let’s Review What is weather?
Weather is the condition of the troposphere at a particular time and place.
What is climate?
Climate is the average weather of a place. (the pattern of weather in an area)
What kind of climate does Tennessee have?
Tennessee has a mild climate with warm summers and cool winters. Rain usually falls in the winter and early spring.

7. So knowing the climate of Tennessee, what are the factors or variables that are important in determining the climate of an area?
temperature and rainfall
Thinking globally (the whole Earth) what do you think has the strongest effect on the climate? Think about a globe and what stands out on a globe…
The Latitude of the area or the distance north or south of the equator is the strongest factor. For example, the northern United States has a colder climate than the South.

8. What is air pressure?
You can think of air pressure as the weight of a column of air pressing on a patch of the Earth’s surface about the size of your thumbnail. It is the force placed on a given area. You do not feel this weight because atmospheric pressure pushes in all directions and these pushes balance each other.

9. Climate Zones
-How does the climate of the states near the West Coast compare to those of the East Coast?
-What is the climate of Tennessee?
-Climate Map

10. How do oceans affect temperature on land?
The climate of a place near the ocean is usually milder than a place inland.
Think if you placed your hand over a sink filled with warm water, you will feel the warmth. This is because heat from the water is warming the air between your hand and the water. Air that is in contact with a body of warm water is warmed in the winter and cooled in the summer. The temperature of land increases faster than the temperature of water.

11. Sea Breeze
The air above land also warms faster than the air above water.
Sea Breeze and Land Breeze
What is sea breeze?
A sea breeze is when air moves from water to land.
What is land breeze?
A land breeze is when air moves from land to water.

12. How do oceans affect temperature on land?
sea breeze day
Key
land breeze night
Discuss the Main Idea
Remind students that temperatures along the coast are generally different from inland temperatures. Ask:
Are temperatures along the coast usually more extreme or milder than those inland? Explain.
Milder; Water cools and heats more slowly than land does, so temperatures near the ocean are often less extreme than temperatures inland.
Develop Vocabulary
Have students use the terms sea breeze and land breeze as they write a paragraph that summarizes what they know about how oceans affect temperatures on land.
Quick Check
(Main Idea and Details) Describe the movement of air during a sea breeze and a land breeze?
In a sea breeze, the cooler, higher-pressure air over the ocean moves toward the warmer, lower-pressure air over the land. In a land breeze, the cooler, higher-pressure air over the land moves toward the warmer, lower-pressure air over the ocean.
(Critical Thinking) How could you show that land heats up faster than water?
Possible answer: Fill a cup with sand and fill a cup with an equal amount of water. Place a thermometer in both cups. Place both cups under a heat lamp. Observe which cup increases in temperature faster.
warm air
cold air

13. Review
Describe the movement of air during a sea breeze and a land breeze.
In a sea breeze, the cooler, higher-pressure air over the ocean moves toward the warmer, lower- pressure air over the land. In a land breeze, the cooler, higher-pressure air over the land moves toward the warmer, lower-pressure air over the ocean.

14. How do mountains and ocean currents affect climate?
A current is the constant movement of ocean water.
BrainPop- Ocean Currents
What kind of temperatures do areas near a cool current have?
Land areas near cool currents such as the California current, often have cool temperatures.
What kind of temperatures do areas near a warm current have?
Land areas near warm currents, such as the Gulf Stream, tend to have warm temperatures.

15. How do mountains and ocean currents affect climate?
Discuss the Main Idea
Explain to students that the movement of ocean currents and the presence of mountain ranges can affect the climate of a region. Ask:
How can ocean currents traveling from near the equator affect the climate of a region?
It can make the region warmer than it would otherwise be.
How can a mountain range affect the climate of a nearby region?
Possible answers: It may block polar winds, keeping the region warmer; it may cause rain clouds to dump their water on the windward side; keeping rain from reaching the leeward side.
Develop Vocabulary
current Word Origin The word current is from the Latin word currere, which means “to run.” A current flows, or “runs,” in a body of water, such as the ocean.
rain shadow Refer students to the illustration on page 237 and use it to show why one side of the mountain is in the “shadow” of the rain. Discuss how the altitude of the mountain makes it possible for the two sides to have different climates.
Quick Check
(Main Idea and Details) Why is the climate of an area on the windward side of a mountain different from the climate on the leeward side?
As warm air moves up the mountain, it condenses and precipitation forms. The air that moves down the other side is dry and hot.
Why are most of the currents that flow near the equator warm currents?
Temperatures for areas near the equator are much higher than for other areas.
What do the arrows on the map represent?
What types of currents run along the equator?
The currents along the equator are warmer.

16. How do mountains and ocean currents affect climate?
Ocean current moves heat around the world in ocean. They also move heat around the world in the atmosphere through water vapor. What happens around the equator when the heat energy from the sunlight heats the water? (Water Cycle)
The water evaporates forming water vapor.
Global winds carry the water vapor to cooler regions away from the equator. As it is moved to cooler regions, the water vapor condenses, releasing heat into the atmosphere. The transfer of heat around the world through the atmosphere and through the water is an important way that oceans keep temperatures on Earth within a narrow range.

17. Review of the Water Cycle

18. How do mountains and ocean currents affect climate?
Altitude is a measure of how high a place is above sea level. The higher a place’s altitude is, the cooler its climate.
One side of the mountain may get a lot of rain while the other side receives very little. As warm, moist air moves up a mountain, it gets cooler, water vapor condenses, and precipitation falls on one side of the mountain. This side of the mountain is called the windward side.
The air that moves down the other side of the mountain, the leeward side (lee=leaving), is dry and hot. The dry area on the leeward side of the mountain is called a rain shadow.

19. How do mountains and ocean currents affect climate?

20. Review
Why is the climate of an area on the windward side of a mountain different from the climate on the leeward side?
As warm air moves up the side of the mountain it condenses and precipitation forms. The air that moves down the other side is dry and hot.
Why are most of the currents that flow near the equator warm currents?
Temperatures for areas near the equator are much higher than other areas. (Where does the sun’s rays shine most of the time?)

21. El Nino
El Nino is a weather condition that causes severe weather (heavy rain and storms) in different areas of the Pacific.
It occurs when the cold current that flows along the coast of Peru moves deeper, allowing the water near the surface to warm up. It causes air pressure to be higher on the eastern Pacific than it is in the western Pacific.
La Nina is a weather condition in which the cold ocean current moves closer to the surface and the air pressure in the eastern Pacific Ocean increases. It brings drier weather to the coastal areas of North and South America.

22. What is El Niño?
normal conditions
El Niño conditions
La Niña conditions
Discuss the Main Idea
Ask students whether they have heard of El Niño. Discuss what students know about El Niño. Ask:
What is El Niño?
Possible answers: a weather condition that causes severe weather in different areas around the Pacific
What causes El Niño?
the cold current that flows along the coast of Peru moves deeper, allowing the water near the surface to warm up
What is La Niña?
a weather condition in which the cold ocean current moves closer to the surface and air pressure in the eastern Pacific Ocean increases
Develop Vocabulary
El Niño: Tell students that this Spanish term means “the child” in English. It is the masculine form; La Niña is the feminine form.
Explain that the weather pattern known as El Niño-Southern Oscillation is abbreviated ENSO. The conditions oscillate between the El Niño, La Niña, and normal conditions.
Quick Check
(Main Ideas and Details) What weather patterns could be occurring if the air pressure along the coast of Peru is low?
an El Niño
(Critical Thinking) What conditions occur in Australia during an El Niño?
The air pressure over Australia is higher than usual and the air becomes very dry.
El Niño occurs every two to seven years when the cold current sinks and stops pushing cold water up to the surface.

23. The differences… Normal El Nino El Nina Surface Water cool, high
warmer, low
Winds
east to west
west to east
Weather
normal
wet
dry

24. Review
What weather patterns could be occurring if the air pressure along the coast of Peru is low?
An El Nino
What conditions occur in Australia during an El Nino?(look at diagram on p. 238)
The air pressure over Australia is higher than usual and the air becomes very dry.