Name of Resource: What Factors Impact a Greenhouse?
Climate Change Theme: Greenhouse Effect
Sponsoring Organization: UCAR
Intended use: Non-computer activity
Intended audience: Educator and Learners
Average Review Ratings (Poor to Excellent, 1-5 scale):
Description: This activity has students use a model to investigate factors in greenhouse heating and cooling. The type of surface that sunlight first encounters is the most important factor. Forests, grasslands, ocean surfaces, ice caps, deserts, and cities all absorb, reflect, and radiate radiation differently. As a result of this activity students will be able to identify at least three factors affecting the heat-trapping ability of a greenhouse, explain the factors important in the atmosphere's heat trapping ability, and understand the influence of albedo on earth's temperature.
Summary of Reviews
Reviewer: Carrie Morrill
Comments: Provides mostly-accurate information about the greenhouse effect and a hands-on activity about albedo. There is some good stuff here, but additional thought and caution are needed to present concepts in a scientifically-accurate way. Learning goals of the exercise are misleading: albedo does not affect the "heat trapping ability of a greenhouse"– the concentrations of greenhouse gases do that. There can be feedbacks between the greenhouse effect and albedo, and albedo can itself influence the earth's radiative balance. The learning goals of the exercise should be based around these points.
Read entire review: link text (Acrobat (PDF) 65kB Jun21 05)
Reviewer: Kirsten Butcher
Comments: Easy to follow discussion of the greenhouse effect. The few visual aids presented are used rather effectively. Some information could be better explained. For example, the site talks about global warming melting snow and ice cover– potentially exposing dark surfaces which could increase global warming. The site says "The magniture of the effect is currently a matter of serious scientific study and debate." But the site does not discuss what factors are controversial, how scientists approach the controversy...or what informs the debate. The site would be improved by more in-depth analysis of these issues. Seems to be a bit of a disconnect between the complexity of the effects that are presented in the text and the simplicity of the activity. I wonder if students will be mislead by the simplicity of the exercise– they may be tempted to overgeneralize their activity results to what is actually a very complex phenomenon. Activity is well-presented. Materials list and instructions appear to be clear and complete. Good assessment ideas that present methods to test understanding (rather than just memory) through transfer of knowledge to new situations.
Read entire review: link text (Acrobat (PDF) 63kB Jun21 05)
Comments: Need to be aware of the time frame. It is listed as a 60 minute activity, but most classes are approx. 45 minutes long. I would want to test the process to see if the lamps available would be able to evenly heat the 6 bottles at one time. I also would want to be sure all the materials were at room temperature to start with, especially if students are putting the items in the bottles as part of their lab. The paint job would also need to be very even for the bottles in order to compare results.
Read entire review: link text (Acrobat (PDF) 39kB Jun21 05)
Reviewer: Robert Croft Comments: Question accuracy of all material. Explanations are too simplistic and need more information such as "significant fraction of the solar radiation is captured by the plants." Is 3% a "significant fraction"? Good activity that attempts to teach an important concept. However, it is not practical to do in a classroom with 30 students and then do the activity 5 or 6 times a day. Classrooms usually do not have that kind of space for set up and/or not enough electrical outlets for light sources.
Read entire review: link text (Acrobat (PDF) 46kB Jun21 05)
Comments:This site provides comprehensive background information on the greenhouse effect. Topics range from solar radiation, greenhouse gases, Earth痴 radiation budget, to the greenhouse effect itself. Two hands-on activities about greenhouses with both teacher and student guides are also included.
Read entire review: link text (Acrobat (PDF) 51kB Jun21 05)