PhET Greenhouse Effect Objective: Describe how the "greenhouse effect" affects temperature on the earth and to use evidence to support whether the "greenhouse effect" is good or bad for the earth. Introduction: Global warming is perhaps the "hottest" topic in today's headlines. The cause of warming is usually blamed on the "greenhouse effect" or "greenhouse gases." The following simulation will allow you to first examine how the "greenhouse effect" works in a greenhouse. You will then experiment with a simulation of the earth's atmosphere where the concentration of greenhouse gases can be varied. You will use the results of the two simulations to describe how the "greenhouse effect" affects temperature on the earth and discuss whether the "greenhouse effect" is good or bad for the earth. You will compare the levels of greenhouse gases to different periods in the earth's history and examine their effects. Finally, you will examine different molecules that make up our atmosphere and determine which ones are better at absorbing photons. Before diving into the whole issue of global warming, try to picture sitting in an enclosed car on a cold but sunny day ... pretty comfortable, isn't it. Now imagine sitting in that same car on a hot, sunny day. Don't hold that image too long. You'll fry just thinking about it. Now you know why it is so important not to leave children or pets in a car unattended. NOTE: For electronic submission, type your answers in the blocks provided. If you intend to turn in a hardcopy, ensure you have enough room for each answer prior to printing. 1. Hypothesize why the inside of a car feels so much warmer than its surroundings on sunny days. 2. Go to http://phet.colorado.edu/en/simulation/greenhouse. Click "Run Now" The Greenhouse Effect (2 04) File Help Greenhouse Effect Glass Layers Photon Absorption Legend - Sunlight photon infrared phoron Greenhouse Gas Concentration- None Lots Atmosphere during Today 1750 ke age Adjustable concentration Greenhouse Gas Composi 120 70% rel humidity CO, 388 ppm Ci4 1.843 pam N20 0.317 UDM Options a Number of Chunla Thermometer Fahrenheit Callus On on View an photonsPart I: A Greenhouse Simulation 1. Select the "Glass Layers" tab. 2. What do the yellow stars represent? 3. What do the red stars represent? 4. Both the yellow and red stars represent forms of energy in the form of photons: the yellow are visible light, the red are heat. 5. Record the approximate temperature "inside the greenhouse" before adding glass panes. 6. Add one glass pane. What do the sunlight photons do when they hit the glass from the top? 7. What do the infrared photons do when they hit the glass from the bottom? Be specific. 8. What is the new temperature "inside the greenhouse?" 9. Based on the observations of the photons, why does the temperature go up so much? 10. What happens to the temperature as additional glass panes are added? 11. Explain why this happens by observing the photons. 12. Before proceeding to the earth, predict how what you have discovered regarding greenhouses might apply to the earth and its atmosphere