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 photonsToday 1. Click on the "Today" button and record the minimum temperature. 59 F 2. Record: CO2_ CH4 N20 3. What happens to the sunlight photons as they hit the ground? 4. What happens to the temperature when you add clouds? 5. How are the photons affected by adding clouds? Comparison 1. Describe how, according to the model, the effects of Greenhouse Gases on the Earth's atmosphere have changed from the Ice Age to today. 2. What assumptions do you think the model is making? Do you think those assumptions are valid? 3. What would happen if there were no Greenhouse gases? (Adjust the Greenhouse Gas Concentration Level to None.) 4. What will happen if Greenhouse gases increase in the future? (Adjust the Greenhouse Gas Concentration Level to Lots.) 5. Identify some natural or human processes that might increase or decrease the amount of greenhouse gases in the atmosphere. Conclusion