1. Unit 5 Lesson 2 What Are Types of Weather?
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2. Up in the Air Warm up 1 Unit 5 Lesson 2 What Are Types of Weather?
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3. Unit 5 Lesson 2 What Are Types of Weather?
Up in the Air
Earth’s atmosphere protects us from the sun’s harmful ultraviolet rays and shields Earth from space debris.
The atmosphere is a mixture of gases and is mostly made up of nitrogen and oxygen.
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4. Unit 5 Lesson 2 What Are Types of Weather?
Up in the Air
Weather is the condition of the atmosphere at any given time and place. Weather takes place in the layer of the atmosphere closest to Earth’s surface.
Without the movement of gases in the atmosphere, there would be no weather.
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5. Unit 5 Lesson 2 What Are Types of Weather?
Up in the Air
Many factors, including air temperature, humidity, and air pressure help us describe the weather of a place.
Air temperature is how warm or cool the air is around us.
Air temperature affects how much moisture is in air, how we dress, and what we do outside.
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6. Up in the Air Humidity is the amount of water vapor in the air.
Unit 5 Lesson 2 What Are Types of Weather?
Up in the Air
Humidity is the amount of water vapor in the air.
When the air feels dry, we have low humidity.
When the air feels damp, we have high humidity. High humidity can affect precipitation.
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7. Unit 5 Lesson 2 What Are Types of Weather?
Up in the Air
Air pressure is the weight of the atmosphere pressing down on Earth’s surface.
Air temperature and humidity both affect air pressure.
Changes in air pressure
usually bring changes in weather.
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8. Up in the Air Unit 5 Lesson 2 What Are Types of Weather?
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9. Up in the Air Exit slip 1 Unit 5 Lesson 2 What Are Types of Weather?
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10. Under pressure warm up 2 Unit 5 Lesson 2 What Are Types of Weather?
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11. Unit 5 Lesson 2 What Are Types of Weather?
When the Wind Blows
The sun warms Earth’s surface unevenly, which causes differences in air pressure.
Air moves away from areas of high pressure to areas of low pressure. This movement of air is called wind.
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12. Unit 5 Lesson 2 What Are Types of Weather?
When the Wind Blows
Areas near Earth’s poles receive less sunlight than areas near the tropics. At the poles, the air is cold and has higher pressure. As a result, air moves from the poles toward the tropics.
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13. Unit 5 Lesson 2 What Are Types of Weather?
When the Wind Blows
At the tropics, air warms, rises, and moves toward the poles.
These winds, called global winds, blow over large areas of Earth. Global winds move large weather systems, such as hurricanes.
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14. Unit 5 Lesson 2 What Are Types of Weather?
When the Wind Blows
Local differences in temperature can also cause winds. Earth’s surface heats up at different rates.
For example, the side of a mountain heats up more quickly than the valley below. As a result, a valley wind forms as air moves from the valley up the side of the mountain. This is an example of a local wind.
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15. Unit 5 Lesson 2 What Are Types of Weather?
When the Wind Blows
Local winds move in short distances and can change direction.
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16. Unit 5 Lesson 2 What Are Types of Weather?
When the Wind Blows
An anemometer measures wind speed. Wind pushes against the cups on the anemometer, causing them to spin. The rate at which the cups spin is measured to determine wind speed.
A wind vane points in the direction from which wind blows.
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17. Unit 5 Lesson 2 What Are Types of Weather?
When the Wind Blows
Sea breezes happen during the day when the land is warmer. Cooler, higher-pressure air flows from over the water to the land, forming a sea breeze.
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18. Unit 5 Lesson 2 What Are Types of Weather?
When the Wind Blows
Land breezes happen at night when the land is cooler. Cooler, higher-pressure air flows from the land toward the sea, forming a land breeze.
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19. When the Wind Blows Exit slip 2
Unit 5 Lesson 2 What Are Types of Weather?
When the Wind Blows Exit slip 2
Label the diagram using the words ( sea breeze – land breeze)
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20. When the Wind Blows Warm up 3
Unit 5 Lesson 2 What Are Types of Weather?
When the Wind Blows Warm up 3
How would wind be different if the sun heated the Earth’s surface evenly?
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21. Unit 5 Lesson 2 What Are Types of Weather?
How Clouds Form
Air often contains water in the form of a gas called water vapor.
Clouds form as water vapor cools and condenses.
A cloud is made up of tiny water droplets and ice crystals, so small that air currents hold them up.
There are three main types of clouds, cumulus, cirrus, and stratus.
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22. Unit 5 Lesson 2 What Are Types of Weather?
How Clouds Form
Cumulus clouds are white, puffy, and common on clear, sunny days. Cumulus clouds can develop into massive thunderstorm clouds (cumulonimbus).
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23. Unit 5 Lesson 2 What Are Types of Weather?
How Clouds Form
Cirrus clouds look like thin, white streaks, high in the air. They usually signal cool, fair weather.
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24. Unit 5 Lesson 2 What Are Types of Weather?
How Clouds Form
Stratus clouds are low and gray, making the day dark and gloomy. These clouds produce or signal rain or snow.
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25. Unit 5 Lesson 2 What Are Types of Weather?
How Clouds Form
Which clouds are cirrus? which are cumulus? Which are stratus?
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26. Unit 5 Lesson 2 What Are Types of Weather?
Some Rain, Anyone?
Precipitation forms when water particles inside of clouds grow too large and fall to Earth’s surface.
There are four common types of precipitation: rain, snow, sleet, and hail.
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27. Some Rain, Anyone? Rain falls as liquid water.
Unit 5 Lesson 2 What Are Types of Weather?
Some Rain, Anyone?
Rain falls as liquid water.
Snow is solid precipitation that falls as ice crystals, or snowflakes.
Sleet is made of small lumps of ice that form when rain falls through freezing air.
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28. Unit 5 Lesson 2 What Are Types of Weather?
Some Rain, Anyone?
Hail is made of layers of ice that form inside thunderstorm clouds, ranging in size from smaller than a pea to larger than a grapefruit.
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29. Video Some Rain, Anyone? Unit 5 Lesson 2 What Are Types of Weather?
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30. Unit 5 Lesson 2 What Are Types of Weather?
Some Rain, Anyone?
Many factors affect the type of precipitation that falls in a place.
Snow is common in the winter, at the poles, and in places with high elevations.
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31. Unit 5 Lesson 2 What Are Types of Weather?
Some Rain, Anyone?
Too much precipitation can cause rivers to overflow. Floodwaters can damage crops and homes.
Too little precipitation is a drought. During a drought, the ground dries out and plants and animals can die.
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32. Some Rain, Anyone? Exit slip 3
Unit 5 Lesson 2 What Are Types of Weather?
Some Rain, Anyone? Exit slip 3
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