Lab 2: Climate and Earth's Energy BalanceThe lab activities in this module were developed by Betsy Youngman of TERC for the EarthLabs project.
Use the button at the right to navigate to the student activity pages for this lab. To open the student pages in a new tab or window, right-click (control-click on a Mac) the "Open the Student Activity" button and choose "Open Link in New Window" or "Open Link in New Tab."
Investigation Summary and Learning Objectives
Students build and examine a diagram of Earth's energy balance, discussing the inputs, transfers, and outputs of the system. They complete lab activities to demonstrate the natural greenhouse effect and the enhanced greenhouse effect due to the addition of greenhouse gases. They also view an online animation of insolation (incoming solar radiation), albedo, and surface temperature over a multi-year period.
After completing this investigation, students will be able to:
- describe how incoming solar radiation is reflected, absorbed, and transferred throughout the Earth system;
- model Earth's energy flow and budget, both qualitatively and quantitatively;
- list the major greenhouse gases and their role in planetary balance; and
- describe the role of the water cycle in maintaining Earth's energy budget.
For more information about the topic, check the section titled Background Information under Additional Resources below
Activity Overview and Teaching Materials
In Part A: Students use a combination of computer animations, readings, and a hands-on lab as they deepen their understanding of Earth's water cycle and how it relates to the Earth's energy balance. This lab can be completed offline. Teachers can print out the lab instructions to share with the class.
Time required: 50 minutes
In Part B: Students learn about the energy inputs and outputs that result in Earth's temperature ranges, as we know them today. The lab begins with a simple thought exercise about the thickness of the troposphere, or region of weather. Students then view several interactive animations that diagram out the pathways by which energy enters and exits the Earth system. They complete a hands-on activity to account for the energy in each of the pathways. This lab requires a live Internet connection and simple lab materials. It can be broken into two parts; the first requires Internet while the second part can be completed offline.
Time required: 50 minutes
In Part C: Students use both video and computer-based animations to learn about the "greenhouse" effect of carbon dioxide. This lab requires a live Internet connection. Reading materials can be printed out ahead of time and distributed in class or used as homework.
Time required: 40 minutes
In Part D: Students complete a hands-on simulation of the greenhouse effect using simple lab materials. Students compare the global warming potential of water vapor, carbon dioxide, and dry air.
Time required: 50 minutes
Tools needed: Internet browser, Adobe Reader, Flash Player, Lab Materials (described below).
Time required: 150-200 minutes, or 3-4 class periods are needed to complete these labs. (Part B and C reading assignments can be done as homework.)
To download one of the PDF or Word files below, right-click (control-click on a Mac) the link and choose "Save File As" or "Save Link As."
- Stop and Think Questions (Word (Microsoft Word 546kB Dec6 12) and PDF (Acrobat (PDF) 468kB Dec6 12))
- Suggested Answers (Microsoft Word 2007 (.docx) 607kB Dec6 12) to Stop and Think Questions
- Lab 2B: Energy Balance Instructions (Acrobat (PDF) 2.6MB Mar29 13) PDF file contains instructions for the activity. A separate Energy Balance recording sheet (Acrobat (PDF) 564kB Mar29 13) is available for printing.
Teaching Notes and Tips
Part A: Simple lab materials, described on the student page, are needed for this part. It is suggested that teachers set up and practice this lab ahead of class in order to anticipate issues. Parts of this lab (and the labs in Parts B and D) can be done as a demonstration or as a stations-type activity.
Materials needed for this lab include:
- Clear glass or plastic aquarium or shoebox
- Lid for aquarium or shoe box, can be a piece of cardboard and / or plastic wrap
- Rubber bands to hold the plastic wrap in place, if used. Hint: to make a long rubber band tie several shorter ones together
- A gallon- or quart-sized ziplock bag filled with sand, gravel or soil
- Warm water
- Blue food coloring (optional)
- Small cup or ziplock bag for ice
- Desk or clamp-on type lamp, the wattage of the bulb should be 40-60 watts. Alternately, you can place the apparatus in the bright sun.
In Parts B and C: These labs introduce students to two of the most significant (and complex) phenomena related to our planet's climate: Earth's radiation balance and greenhouse gases. Misconceptions related to these two topics are commonplace among both students and the adult population. Reviewing Parts B and C carefully and reading the articles accessible from the links under the Background Information section, below, will help prepare you to address some of these misconceptions. The primary drivers of climate are: incoming solar radiation, the composition of the atmosphere, Earth's revolution and rotation, and the character of the surface of the Earth. In these labs, students will study the first two of these four drivers. Depending on your students' prior knowledge, you may want to discuss the important fundamental principle of Earth's spherical shape and how the incoming sunlight is distributed unequally on a sphere.
Part B: Simple lab materials, 100 stackable objects such as: pennies, paper squares, poker chips, Lego, or small cubes and several sheets of paper, are needed for each lab team. There is a detailed list on the student page. Download and print this Energy Balance recording sheet (Acrobat (PDF) 564kB Mar29 13), and a copy of the Energy Balance Instructions (Acrobat (PDF) 2.6MB Mar29 13) PDF file to read as you work through the lab. It is suggested that teachers set up, read the background articles, and practice this lab ahead of class in order to anticipate issues. A more detailed version of the energy balance diagram is shown in the hidden below. This diagram and explanation may be of interest to teachers and advanced students.
From the March 2009 paper "Earth's Global Energy Budget" by Kevin E. Trenberth, John T. Fasullo, and Jeffrey Kiehl in the Bulletin of the American Meteorological Society, Source: American Meteorological Society
Teachers and students want to review a similar diagram and accounting of energy shown on the following NOAA page: Earth-Atmosphere Energy Balance Diagram
Part C: Students use several interactive animations in this part. Teachers can show these animations as a full-class activity or assign them for homework. The video Piecing Together the Temperature Puzzle may take several minutes to download on some computers. Teachers may want to check this connection and / or show the video to the whole class via a projector. (mpv4 formatplays in real player or windows media player). Some teachers may choose to use the video as an introduction to the activity. The lab concludes with a discussion of the role of greenhouse gases in climate. Allow time for the discussion.
Facilitation tips: Write the primary discussion questions on the board and give students three minutes to share ideas in pairs or to write in their notebooks before starting the full class discussion.
Primary discussion question: After completing this lab, discuss your thoughts about the material covered in this lab with your classmates. Consider the following questions:
- Why do we study the planet as one interconnected system?
- How do we know that the Earth's climate is changing, and what is the role of GHG in that change?
Supporting/Follow-up questions: To help jump-start the students thinking, or to further probe their knowledge, use the following questions:
- What is a greenhouse gas? Give two examples of greenhouse gases.
- Why are greenhouse gases important to life on Earth?
- How are the atmosphere, hydrosphere, geosphere, and biosphere connected?
- How do we monitor Earth with satellites? What types of data are collected by satellite?
- What are two signs of the Earth's warming?
- What are the three major pieces of the climate puzzle studied by NASA satellites?
- Why is it important to understand the Earth's radiation balance?
Wrap Up: Revisit the primary discussion question for consensus or summarize the discussion highlights.
Part D: Lab materials are needed for this part. There is a detailed list on the student page. It is suggested that teachers use the pre-lab preparation notes and set up and practice this lab ahead of class in order to anticipate issues. Note: getting sufficient CO2 in the bottle in order to see measurable results can be challenging. It is important to have sensitive thermometers. Inexpensive, and accurate, digital temperature probes can be purchased online at 9mart digital temperature sensor. Read through the instructions with the class before beginning lab. Note that water vapor is also an important greenhouse gas, that is the reason it is included in this lab. A completed data file is provided for teacher use. Right-click to download and save the file. Greenhouse Gas Lab Results in Excel (Excel 2007 (.xlsx) 43kB Jul31 11) As an alternative, teachers may want to substitute this YouTube video from Myth Busters in place of the lab.
Parts of this lab (and the labs in Part A,B, and D) can be done as a demonstration or as a stations-type activity.
Student NotebooksThe following items are suggestions for inclusion in optional printed student notebooks. The materials are linked in the Printable Materials section, above.
- Key Questions listed in introduction to lab
- Stop and Think questions
- Discussion Starters and a place to write notes
- Relevant vocabulary and a place to write definitions
- Extra blank sheets for sketches or notes
- Lab handout from lab 2A
- Lab activity for Energy Balance Activity 2B
AssessmentThere are several options for assessment of student understanding of material introduced in this lab. Teachers can choose from the following list, or create their own assessments.
State and National Science Teaching Standards
TO BE PROVIDED LATER
Developer will correlate activity to standards listed at this site:National Science Education Standards (SRI)
Background InformationAdditional background reading about the greenhouse effect and global warming can be found at the following links:
- NOAA Global Warming FAQ
- NOAA Greenhouse Gases FAQ
- NASA Greenhouse Gases
- Energy Balance Article
- The Earth-Atmosphere Energy Balance
- London Science Museum - climate change exhibition
- Water Cycle Article at NASA Earth Observatory
- NOAA Jetstreambackground information about the water cycle and its role in weather and climate.
Content ExtensionDepending on the interest level and ability of students, the following links and activities can be added to this lesson.
- Teachers may decide to have students read and share the background articles, linked above, about greenhouse gases and global warming.
- Additional information and interactive activities on the chemistry and physics of greenhouse gases can be found at this site Global Climate Change Visualizations
- Students who are interested in using NASA data to calculate the Earth's energy balance can complete this online activity. Effect of the Sun's Energy on the Ocean and Atmosphere
- The American Meteorological Society has created this Energy Balance simulation.