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Lesson 1 – Earth’s Atmosphere. Chapter 5 – Earth’s Weather. What is air pressure?. Air is mostly nitrogen & oxygen. Atmosphere is the layers of gas (air) that surround Earth. The atmosphere consists of five layers. Weather happens in the lowest layer, the troposphere.
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Lesson 1 –Earth’s Atmosphere Chapter 5 – Earth’s Weather
What is air pressure? • Air is mostly nitrogen & oxygen. • Atmosphere is the layers of gas (air) that surround Earth. • The atmosphere consists of five layers. • Weather happens in the lowest layer, the troposphere.
What is air pressure? • Air in the atmosphere presses down onto Earth’s surface. • air pressure: the amount of air pressing onto an area • The higher you go, the lower the airpressure.
What can make air pressure change? • Air pressure can be changed by: • amount of space (less space = more pressure) • height above Earth (higher = less pressure) • temperature (warmer = less pressure)
What can make air pressure change? • Air pressure can be changed by: • amount of water vapor, orhumidity (more humidity = less pressure)
What is a barometer? • A barometer is used to measure air pressure.
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