Initial Publication Date: December 12, 2005

Name of Resource: What Is A Greenhouse?
Climate Change Theme: Greenhouse Effect
Sponsoring Organization: UCAR
Intended use: Learning Activity
Intended audience: Educators and Learners
Average Review Ratings (Poor to Excellent, 1-5 scale): 4 stars

Description: Hands-on activity about albedo. There is some good stuff here, but additional thought and caution are needed to present the concepts more accurately. (CM)

Summary of Reviews

Reviewer: Carrie Morrill 4 stars
Comments: 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) 63kB Jun21 05)

Reviewer: Kirsten Butcher 4 stars
Comments: 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 magnitude 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 (through different models? Different assumptions?), or what informs the debate. The site would be improved by more in-depth analysis of these issues.
Read entire review: link text (Acrobat (PDF) 47kB Jun21 05)

Reviewer: Robert Croft 3 stars
Comments: 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) 60kB Jun21 05)

Reviewer: Ellen DeBacker 4 stars
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) 46kB Jun21 05)