This web site contains a general overview of the greenhouse effect.  It includes general and background knowledge as well as an activity that can be adapted to meet your classroom needs.  The focus of the information and the activity is the relationship between the greenhouse gases and the temperature of our earth.  This is the center of our understanding about the global warming phenomena.

The lab investigation and the content is simplistic and basic in its concept; however, extended web sites and activities are provided to facilitate the activities and content you may want to include.  The lab activity focuses on the relationship of greenhouse gases having a direct effect on the amount of infrared rays striking and being absorbed by a surface which affects the atmosphere's temperature.   This activity and web site tries to answer the question 'What is the Greenhouse Effect?'
 

The  Earth's atmosphere works similarly to an actual greenhouse.  The major difference between the earth's atmosphere and an actual greenhouse is that the gases in our atmosphere trap the heat, preventing it from escaping to quickly.   In addition to the gases entrapping the heat, they are necessary for human life support.  The major Greenhouse gases are Water Vapor (H₂O(g)), Carbon Dioxide (CO₂),  Methane (CH₄), Ozone (O₃) and Nitrous Oxide (N₂O).

These gases allow the sun's energy to pass through via visible and ultra-violet radiation to the earth's surface trapping much of the energy within the atmosphere. The atmosphere in turn acts like the glass in a greenhouse, allowing for the short -wave ultra violet radiation to travel through unimpeded. When the earth radiates the unabsorbed energy back  up to the atmosphere, it is in the form of  long wave infra-red radiation. This process causes  the net warming of the earth  and atmosphere creating Earth's natural greenhouse effect. This enables the Earth to maintain an average of 15 degrees Celsius, without the effect, surface temperature would drop drastically to (–18) degrees Celsius and be unable to support life. This natural effect is essential for our survival, however, there has been an increase in these gases.
  

It is only necessary for a small amount of these gases to remain in our atmosphere while the majority reflects back to space or are absorbed into normal sinks. However the cycle is beginning to feel the affects of our over- indulgence and it's demonstrated by many global changes. No one is certain that the gas elevation is solely to blame or if the earth is going through its own cyclic changes.

Since there hasn't been  conclusive research performed we can only speculate on what the affects will be. But there have been many drastic occurrences such as :El Nino,extreme heat waves, enormous amounts of rainfall and an increase of pollution to name a few.

 What should teachers be aware of ?

Students should have  prior knowledge of what the greenhouse effect means and have discussed the properties of soil, sand, and water as it relates to the absorption of solar energy.

Preparation time: set up will take approximately 20 minutes.

Lab Time: approximate class time needed is about 45 minutes.

Precautions : DO NOT put the end of the thermometer bulb into the soil.  (You are measuring the atmospheric temperature not the soil temperature.)

Target Audience: for this activity Grade 5-9. Please keep in mind that extensions of the activity may be accomplished for 10-12th graders.
                                                                                                                                                                                                                                           

  2.Students will build and test  physical models analogous to the atmospheric greenhouse effect

  3.Students will compare models of two greenhouse gas systems carbon dioxide gas and correlate
      properties of gas with degree of soil.

  4.Students will be introduced to concepts of energy transter and thermal equilibrium.

  5.The student shall  classify, order, and sequence data relating to matter and  energy.

  6.The student shall communicate data and information in appropriate oral and written form.
   

Introduction

The purpose of this lesson is for the students to investigate and model the greenhouse effect.  Students should follow the scientific method and formulate a hypothesis as to the rate of the heat absorption for both the experiment and the control model. 

Materials
 

2 two liter plastic soda bottles (washed out)            scissors or box cutter     2 long thermometers                                                     3 strips of cardboard (1/2" x 1")                                  soil     sand                                                                               water (in spray bottle)                                                 plastic wrap     rubber bands (medium size)

masking tape    heat lamp    scooper for the dirt    metric ruler    graph paper    color pencils    graphing calculator (optional)    CBL / temperature probe (optional)

   

Procedure 

1. Cut two liter bottles at the point where the neck begins to narrow.
2. Tape the thermometers and strips of paper inside each bottle. (The cardboard is used to cover the bulb end of the thermometer to protect from direct rays of the light bulb.)
3. Fill each liter bottle with two cups of soil.
4. Dampen the soil with water from the spray bottles. Count and use the same number of sprays for each bottle of soil.
5. Cover one bottle with plastic wrap and keep the bottle secure with a rubber band.  The other bottle will be left open and will be the control bottle.
6. Position the lamp approximately 20 to 30 centimeters above the bottles.
7. Record the beginning temperature for each bottle.
8. Turn the lamp on.
9. Record the temperature every minute for 15 minutes.
10. After you are finished recording the temperature, graph your data by plotting the temperature on vertical axis and time on the horizontal axis.  One colored pencil can be used to graph the experimental reading as a solid line and the control reading as a dotted line.  Also, the use of the CBL and graphing calculator can be used to measure temperature.
 

Discussion/Conclusion

1.What happened to the temperature in both the control and experimental bottle for all treatments?  Explain.

2.What was the final outcome of the temperature in the control and experimental bottle?  Explain.

3.Based on question 2, was there any difference in the experimental and the control bottle? Explain.

4. What purpose did the control serve in the experiment?

5. What do you think would occur with the temperature if different soil colors were used?

6. Why should the number of spray from the water bottle remain constant throughout the procedure?

7. What other variables should be considered in this experiment that might affect that outcome of the data?

8. How might this experiment be extended to investigate the absorption of heat energy in different regions on the surface of the earth?
 

Applying the Knowledge

A. How do the results of the activities in these exercises relate to the greenhouse effect?

B. What effect does increased cloud cover have on the earth's temperature?  What evidence from this experiment support your answer?

C. What outcome would arise in the average global temperature have on the earth's coastlines?  What other possible effects could an increase in global temperature have on the earth?

D. What can be done to slow down or stop the greenhouse effect? What might prevent progress being made toward solving the problem of global warming?

E. What role does deforestation play in the greenhouse effect and global warming?
 
F. See also Solutions

The greenhouse effect topic can be integrated with practically all subjects: see the following table.
 

Subject	Topics
Biology	Ecosystems, Food Chains, Photosynthesis, Cell division, Growth, Development, Migration,....
Chemistry	Chemical Reactions and Interactions, Mass, Density, Energy,....
Math	Making Charts and Diagrams to plot temperatures, Analysis of Statistics,.....
English	Writing letters to industry, government, and agencies such as the EPA,.....
History	The role of the Industrial Revolution and the increased production of carbon dioxide, global temperatures during the Ice Ages,  the Montreal Treaty,....
Health	Impacts of carbon dioxide on pollution can cause developing health issuse: asthma, skin cancer, bronchitis, sunburn..

                              
                     

Students should have  prior knowledge of how the solar energy produces heat and have discussed  solar energy.

Preparation time: set up will require some work in the preparation stage needing approximately 2  class periods.

Lab Time: approximate class time needed is about 10 minutes for data collection over the period of several weeks.

Lab Data Analysis Time: approximately one class period.

Precautions : DO NOT put the end of the thermometer bulb indirect contact with the glass.  (You are measuring the atmospheric temperature not the glass temperature.)  Handle glass with care. Cover edges of each pane with electrical tape to prevent injury from cut edges.
 
Target Audience: for this activity Grade 5-9. Please keep in mind that extensions of the activity may be accomplished for 10-12th graders.

(Background-Activity II)   
A pane of transparent glass will allow solar radiation to pass through, but not heat. This is the same role that greenhouse gases play in the greenhouse effect.

          1.      Solar radiation can pass through greenhouse gases.
                   [Click solar radiation to see diagram illustrating the greenhouse process.]

           2.     Greenhouse gases are in the atmosphere.

The purpose of this lesson is for students to examine the relationship between  increase in temperature and  increase in  panes of glass.  By asking the question, "Why does the greenhouse effect work?", students will generate a measurable hypothesis by relating number of panes to increased  greenhouse effect.
 
Materials
 

Cardboard

Black construction paper  boxes

3 thermometers for every box

1 classroom thermometer

6 blocks of wood for every box

3 glass panes for every box (have them cut to fit in the box at the store)

Glue

Electrical tape

Scotch tape

 

Procedure

  See Diagrams Below       Top View       Side View

Top View 
Side View

 

Data Table:

Have students examine the relationship between the increase in average daily temperature and an increase in the number of panes of glass.Think about why this is happening. Relate to the greenhouse effect.
A pane of transparent glass allows solar radiation to pass through but not heat. This is the same role that greenhouse gases play in the greenhouse effect. Therefore, in this model, the effect of the increasing number of panes of glass is equal to the effect of increasing greenhouse gas levels.
 
 
 Applying the Knowledge

1.. What happens to a car that has been sitting in the sun on a hot day with all its windows rolled up?
2. Why does the car get so hot?
3. What happens to the sunlight that passes through the windows into the car?
4. What is keeping the heat inside of the car?
5. Solar radiation passes through the gases in the earth's atmosphere. What does  the solar radiation do?
6. What would happen if something were to block the heat from leaving the atmosphere?
7. What blocks the heat from leaving the earth's atmosphere?
  

Activity Resource: Southeastern Michigan Math-Science Coalition
 

CONTENT STANDARD A:  Science as Inquiry
          As a result of activities in grades 5-8, all students should develop the

• Abilities necessary to do scientific inquiry
•  Understandings about scientific inquiry
 
 

•  Properties and changes of properties in matter
• Transfer of energy

CONTENT STANDARD D:  Earth and Space Science
         As a result of their activities in grades 5-8, all students should develop a understanding of:

•   Structure of the earth system
•   Earth in the solar system
 

•  Abilities of technological design
•  Understandings about science and technology
 

• Personal health
• Populations, resources, and environments
• Risks and benefits
 

• Science as a human endeavor
• Nature of science
• History of science

What additional areas can be explored?
This section can be used as a pivotal point for additional  questioning. A broader discussion, either before or after the activity can be achieved with assistance of the WWW.

With increased greenhouse gases how might it affect our climate?
Possible climate change impact areas being researched are

Health
Natural ecological systems
Forestry
Water quality

Air Quality decline resulting in Respiratory Illness
Increase Temperatures changing ecosystems
Infectious Diseases

Impacting questions
1.How did  the results of the activities in these exercises relate to the greenhouse effect?
2.What effect does increased cloud cover have on the earth's temperature?  What evidence from this experiment support your answer?
3.What outcome would arise in the average global temperature have on the earth's coastlines?  What other possible effects could an increase in global temperature have on the earth?
4.What can be done to slow down or stop the greenhouse effect? What might prevent progress being made toward solving the problem of global warming?
5.What role does deforestation play in the greenhouse effect and global warming?

With all problems, a solution must be tangible. What are some things you can do?

The ways to remedy our globe from the continued warming are not simple, but students and communities can explore these options. ( Hopefully this will inspire all to take a good look at their role in the greenhouse effect )

Increase the CO2 absorption by reforestation. One forest tree absorbs 13 pounds of carbon dioxide each year, one acre of trees absorbs 2.6 tons of carbon dioxide annually. Have students contact the National Arbor Day Foundation in order to plant a tree. The school district could launch an event for this by utilizing the Global Relief Kit offered by American Forestry Association at P.O. Box 2000, Washington , D.C. 20013. Planting these trees now can provide for future generations.

Students and adults can think about that second or third car. Believe it or not,  many families have cars for each member of driving age. The need for reducing CO2 emissions is essential. Throughout the world, the production and use of automobiles account for 17% of the CO2 released from fossil fuels. A great angle could be to brainstorm different types of efficient transportation that will release less carbon.

This web site presents the final work of a collaborative group project in inquiry -based curriculum design.  Focus for this project was provided by the Woodrow Wilson Foundation sponsored Enviromental Science Institute, Summer 1998.  The group inquiry process began with identification of a driving question within the broad topic of Global Climate Change.  This group used the driving question: What is the Greenhouse Effect?, as a vehicle for understanding the science involved in the broad topic of climate change. Together, the participants researched current literature, formed a testable hypothesis, designed relevant curriculum, and constructed a web site to communicate its results. We are grateful to the Woodrow Wilson Foundation , Princeton University,  the Facillitators, and all guest lecturers of the institute for this invaluable experience.
   
    

Woodrow Wilson Leadership Program in Environmental Science lpt@www.woodrow.org
The Woodrow Wilson National Fellowship Foundation webmaster@woodrow.org
CN 5281, Princeton NJ 08543-5281 Tel:(609)452-7007 Fax:(609)452-0066