Structure and Composition of the Earth’s Atmosphere

Lesson Objective: 

To gain an understanding of the physical and chemical structure of the Earth’s Atmosphere and understand how changes in the Earth’s atmosphere can/will effect life on this planet.

Subject Matter: 

Earth Science

Grades:
High School Science (9-12)

California Content Standard:  
Structure and Composition of the Atmosphere

8. Life has changed Earth’s atmosphere, and changes in the atmosphere affect conditions for life. As a basis for understanding this concept:

a. Students know the thermal structure and chemical composition of the atmosphere.

b. Students know how the composition of Earth’s atmosphere has evolved over geologic time and know the effect of outgassing, the variations of carbon dioxide concentration, and the origin of atmospheric oxygen.

c. Students know the location of the ozone layer in the upper atmosphere, its role in absorbing ultraviolet radiation, and the way in which this layer varies both naturally and in response to human activities.

  

      Background: 

The Earth's atmosphere is what allows for life to exist on this planet.  Using the web sites listed below you will learn the structure and composition of the atmosphere and the mechanisms it uses to create an environment hospitable for life as we know it.  You will also discover how the atmosphere has changed and what effects that and future change will have on the planet.

Web Resources: 

Use these sites to help you answer the questions in the scavenger hunt.

• NASA:  General information on the Earth's Atmosphere (http://www.nasa.gov/audience/forstudents/9-12/features/912_liftoff_atm.html)
• Vision Learning: General information on the Earth's Atmosphere (http://www.visionlearning.com/library/module_viewer.php?mid=107)
• Healthy Air Living: Information on reducing air pollution (http://www.healthyairliving.com/your-life/)

3.  

Essential Question:

How does out atmosphere make life on Earth possible?

Questions: 

1. Describe the four major layers of the Earth’s atmosphere and give there heights relative to the Earth’s crust
2. What is the chemical composition of each layer?
3. How does the atmosphere protect the surface of the Earth?
4. What portion of the atmosphere affects the weather we experience?  
5. What atmospheric components make life possible and how?
6. What is the significance of ozone in the troposphere and the stratosphere?
7. How does temperature and pressure change throughout the atmospheric layers?  Why is this important?
8.  Was the Earth’s atmosphere always able to sustain life?  What changed to make life on Earth possible?  How long did it take for this change to occur?
9. What are the some of the consequences of changes in the atmospheres composition? 
10. What can we do to help decrease the pollution in the atmosphere?