Using a Mass Balance Model to Understand Carbon Dioxide and its Connection to Global Warming

Robert MacKay, Clark College Physics and Meteorology.

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This page first made public: Oct 23, 2009


Image of CO2 Model Window Students explore the increase in atmospheric carbon dioxide over the past 40 years with an interactive on-line model. They use the model and observations to estimate present emission rates and emission growth rates. The model is then used to estimate future levels of carbon dioxide using different future emission scenarios. These different scenarios are then linked by students to climate model predictions of the IPCC.

Learning Goals

  • Use a model to estimate the future concentrations of carbon dioxide under several different assumed emission scenarios.
  • Learn how different carbon dioxide emission scenarios influence our best prediction of future global temperatures.
  • Learn how a mass balance model applies to the global atmosphere.
  • Calibrate a model with recent observations.
  • Synthesis results into a well written summary.
  • Accurately read graphical information.
  • Read and interpolate data from a table of values.

Context for Use

This activity is useful in any course with a section on carbon dioxide and global warming. It has been used successfully in an introductory meteorology course as well as an upper division course on Earth's Climate for non-majors.

Description and Teaching Materials

The activity and related links are available on-line at (archived). This activity works best with a PC, but with proper configuration also works on MAC OS X.

Assignment Question Sheet (Microsoft Word 125kB Jun3 11) for use with online activity.

Assignment Question Sheet (Acrobat (PDF) 95kB Jun3 11) for use with online activity.

Teaching Notes and Tips

Here are some suggestions for effective classroom use and more details of the mathematics behind the model.


Answers to questions (Acrobat (PDF) 386kB Jun3 11)

Follow up discussions in lecture and exam questions are also useful in assessing student understanding.

References and Resources