9/11/1312th Day of School

Learning Goal (7.E.1.1): I will be able to describe the properties of Earth’s atmosphere.

Due Today: 1st 3 PowerPoint slides

Evening Assignment: Work on atmosphere properties slide of Powerpoint

Do Now

In your composition notebook, copy and answer the following…

What words would you use to describe the properties of Earth’s atmosphere?

McDougall textbook, p. viii

Do Now

Did you get it right?

What words would you use to describe the properties of Earth’s atmosphere?

• Altitude• Density• Temperature• Air Pressure

Defining key words

Why are these properties important?

Look up and write down the definition in your science notebook for the following terms:• Altitude• Density• Temperature • Air Pressure

McDougall textbook, p. A11

Defining key words

What are the properties?

• Altitude: distance above sea level• Density: the amount of mass in a given

volume of a substance• Temperature: how hot or cold an object

is• Air pressure: the force of molecules pushing on an area

McDougall textbook, p. A11

The Composition and Properties of the Atmosphere make life on Earth possible.

1. Living things use gases in the air:• oxygen, nitrogen, argon, carbon dioxide, &

water vapor

2. The atmosphere keeps Earth warm.• Transports energy to different regions of the

planet (radiation, conduction & convection).

3. The atmosphere protects & supports life.

4. Supplies materials that your body uses.

5. The atmosphere is held in place by gravity.

Properties of Earth’s Atmosphere

Altitude and Density• Air becomes thinner as altitude

increases. There is less oxygen.• The thickness or thinness of air is

measured by density.• The atmosphere’s density

decreases as you travel upward. The air on a mountain is less dense than the air at sea level. It contains less mass.

• Most of the mass of the atmosphere is close to Earth’s surface.

McDougall textbook, p. A10

Properties of Earth’s Atmosphere

Temperature• Changes with altitude• Temperature is warmer at

sea level but decreases with altitude in the mountains.

• Measured with a thermometer.

http://eo.ucar.edu/webweather/basic5.html

Air Pressurehttp://eo.ucar.edu/webweather/basic5.html

• Air molecules move in all directions, air pressure pushes in all directions.

• Air pressure decreases with altitude.

• The air molecules in air at sea level are denser than air molecules in air over a mountain.

• Air pressure is higher in dense air than in thin air.

• Areas of high pressure move to areas of low pressure.

• Measured with a barometer.

Major Assessment

Assignment: Earth’s Atmosphere PowerpointYou will make a Powerpoint presentation about Earth’s atmosphere. You may use information and pictures from class, the textbook, other books, and the Internet but you MUST cite your sources (ex. title, page, web address, etc). Include text in your own words explaining any images you use. Your Powerpoint should have the following slides. Final Powerpoint is due Friday 9/13/13.

• Title slide with title, your name, period, date• Slide defining atmosphere• Slide(s) about the composition of Earth’s atmosphere• Slide(s) about the properties of Earth’s atmosphere• Slide(s) about the structure of Earth’s atmosphere

Evening Assignment

Work on Title, atmosphere definition, Earth’s atmosphere’s composition and properties slides.