Jump to this Activity »
Modeling Early Earth Climate with GEEBITT

Cindy Shellito, On the Cutting Edge Collection - Science Education Resource Center (SERC) at Carleton College

In this activity, students gain experience using a spreadsheet and working with others to decide how to conduct their model 'experiments' with the NASA GEEBITT (Global Equilibrium Energy Balance Interactive Tinker Toy). While becoming more familiar with the physical processes that made Earth's early climate so different from that of today, they also acquire first-hand experience with a limitation in modeling, specifically, parameterization of critical processes.

Activity takes one 50-minute class period. Computer access and special software is required.

Discuss this Resource»
Learn more about Teaching Climate Literacy and Energy Awareness»

Climate Literacy
About Teaching Climate Literacy

When Earth emits the same amount of energy as it absorbs, its energy budget is in balance, and its average temperature remains stable.
About Teaching Principle 1
Other materials addressing 1b
The amount of solar energy absorbed or radiated by Earth is modulated by the atmosphere and depends on its composition. Greenhouse gases—such as water vapor, carbon dioxide, and methane—occur naturally in small amounts and absorb and release heat energy more efficiently than abundant atmospheric gases like nitrogen and oxygen. Small increases in carbon dioxide concentration have a large effect on the climate system.
About Teaching Principle 2
Other materials addressing 2c
The interconnectedness of Earth’s systems means that a significant change in any one component of the climate system can influence the equilibrium of the entire Earth system. Positive feedback loops can amplify these effects and trigger abrupt changes in the climate system. These complex interactions may result in climate change that is more rapid and on a larger scale than projected by current climate models.
About Teaching Principle 2
Other materials addressing 2f
Observations, experiments, and theory are used to construct and refine computer models that represent the climate system and make predictions about its future behavior. Results from these models lead to better understanding of the linkages between the atmosphere-ocean system and climate conditions and inspire more observations and experiments. Over time, this iterative process will result in more reliable projections of future climate conditions.
About Teaching Principle 5
Other materials addressing 5c

Excellence in Environmental Education Guidelines

1. Questioning, Analysis and Interpretation Skills:G) Drawing conclusions and developing explanations
Other materials addressing:
G) Drawing conclusions and developing explanations.
1. Questioning, Analysis and Interpretation Skills:C) Collecting information
Other materials addressing:
C) Collecting information.
1. Questioning, Analysis and Interpretation Skills:E) Organizing information
Other materials addressing:
E) Organizing information.
1. Questioning, Analysis and Interpretation Skills:F) Working with models and simulations
Other materials addressing:
F) Working with models and simulations.
2. Knowledge of Environmental Processes and Systems:2.1 The Earth as a Physical System:A) Processes that shape the Earth
Other materials addressing:
A) Processes that shape the Earth.
2. Knowledge of Environmental Processes and Systems:2.1 The Earth as a Physical System:B) Changes in matter
Other materials addressing:
B) Changes in matter.
2. Knowledge of Environmental Processes and Systems:2.1 The Earth as a Physical System:C) Energy
Other materials addressing:
C) Energy.

Benchmarks for Science Literacy
Learn more about the Benchmarks

Greenhouse gases in the atmosphere, such as carbon dioxide and water vapor, are transparent to much of the incoming sunlight but not to the infrared light from the warmed surface of the earth. When greenhouse gases increase, more thermal energy is trapped in the atmosphere, and the temperature of the earth increases the light energy radiated into space until it again equals the light energy absorbed from the sun.
Explore the map of concepts related to this benchmark
Computer modeling explores the logical consequences of a set of instructions and a set of data. The instructions and data input of a computer model try to represent the real world so the computer can show what would actually happen. In this way, computers assist people in making decisions by simulating the consequences of different possible decisions.
Explore the map of concepts related to this benchmark
If a system in equilibrium is disturbed, it may return to a very similar state of equilibrium, or it may undergo a radical change until the system achieves a new state of equilibrium with very different conditions, or it may fail to achieve any type of equilibrium.
Explore the map of concepts related to this benchmark

Notes From Our Reviewers The CLEAN collection is hand-picked and rigorously reviewed for scientific accuracy and classroom effectiveness. Read what our review team had to say about this resource below or learn more about how CLEAN reviews teaching materials
Teaching Tips | Science | Pedagogy | Technical Details

Teaching Tips

  • There are some useful comments on the instructor notes included with this lesson - http://serc.carleton.edu/files/NAGTWorkshops/earlyearth/activities/ArcheanModelInstrucNotes.pdf
  • CO2 levels are listed at 370 ppm in the activity write-up that can be downloaded. This needs to be updated since current levels are over 390.
  • GEEBITT is a modeling tool from NASA configured for HS and post-secondary students to input data on solar luminosity, albedo, and an atmospheric greenhouse gas loading parameter in order to analyze the global mean surface temperature in different climate regimes (Modern, Archean, Neoproterozoic). The NASA GEEBITT tool can be found at: http://icp.giss.nasa.gov/education/geebitt/

About the Science

  • Students use a simple spreadsheet climate model to explore how solar luminosity, albedo, and an atmospheric greenhouse gas loading parameter affect the global mean surface temperature in different climate regimes (Modern, Archean, Neoproterozoic).
  • This activity has students explore model scenarios; real and recent data can be added to the activity by the instructor.
  • The two science articles from Scientific American are excellent.
  • GEEBITT is a 1-dimensional energy balance model (EBM) that calculates global mean surface temperature, based on a planet’s distance from the sun, solar luminosity, global albedo, and a parameterized ‘greenhouse-factor’ (called ‘GHF’ in the activity).
  • Comments from expert scientist: Great exposure to a relevant model. Also allows students to play with the model and investigate several interesting climate questions.

About the Pedagogy

  • Students work in teams of 2 or 3 to conduct a series of computer experiments with the simple spreadsheet model, collect and evaluate data, and then share their results in a class discussion.
  • If class time is short, the class may be divided into three groups, with each group focusing on a different time period (Modern, Archean, Neoproterozoic). At the end of the class, each group must share their results and insights with the class as a whole.
  • This resource may be difficult to do without a familiarity with a number of topics (clarified in the instructions). The readings will help students better understand the times being discussed in Earth's history.
  • Students should be comfortable with using spreadsheets (such as Excel) and spreadsheet models.
  • It would be helpful for teachers to review some of the formulas in the spreadsheet.

Technical Details/Ease of Use

Jump to this Activity »

Have you used these materials with your students? Do you have insights to share with other educators about their use? Please share with the community by adding a comment below.

Please use this space only for discussion about teaching with these particular materials.
For more general discussion about teaching climate literacy please use our general discussion boards.
To report a problem or direct a comment to the CLEAN project team please use our feedback form (or the feedback link at the bottom of every page).
Off-topic posts will be deleted.

Join the Discussion

Log in to reply