CO2 Concentration and the Keeling Curve from the Mauna Loa Observatory
1. Estimate changes in global carbon dioxide concentrations over a 7-year span
2. Learn about variation in the carbon cycle driven by photosynthesis
3. Understand how important sampling interval can be when studying changes over time
4. Practice basic quantitative skills
S.8.D.1.2 - Describe the potential impact of humanmade processes on changes to Earth's resources and how they effect everyday life
Grades 6,7,8: Standard 2.5 - Mathematical Problem Solving and Communication
M.6.D.2 - Represent and/or analyze mathematical situations using numbers, symbols, words, tables, and/or graphs
M.7.D.2 - Represent and/or analyze mathematical situations using numbers, symbols, words, tables, and/or graphs
M.8.D.2 - Represent and/or analyze mathematical situations using numbers, symbols, words, tables, and/or graphs
Preparation Time Needed
Depending on how teachers decide to carry out the exercise, preparation time may be minimal (~15 minutes) to longer. Organizing the data and thinking of how to break students in to groups to work with the data will take the most time for set up.
Class Time Required
This exercise will take at least one one-hour class period. Students may be asked to continue looking at the completed graph and answer additional questions as homework to reinforce skills.
There are many variations of this exercise to have students generate the plot to the left, but I follow the Carbon Dioxide Exercise from the SERC website, where "Students work in groups, plotting carbon dioxide concentrations over time on overheads and estimating the rate of change over five years. Stacked together, the overheads for the whole class show an increase on carbon dioxide over five years and annual variation driven by photosynthesis." This website has the data, a student handout, and pre-formatted graph paper.
Before plotting, your students (as well as mine!) may need help with Plotting Geologic Data in X-Y Space.
A good place to start with the content of this exercise is with an overview is at Teachers' Domain, with their document CO2 Concentrations at Mauna Loa Observatory, Hawaiʻi for grades 6-12. You can visit additional sites to learn about the history of the Keeling Curve, and learn about the Global Monitoring Division of the Mauna Loa Observatory.
The Keeling Curve even has its own website (http://keelingcurve.ucsd.edu/) and Twitter feed that you do not need a Twitter account to access (https://twitter.com/Keeling_curve). The Twitter feed posts daily updates of CO2 measurements, which could be an interesting classroom activity for your students to plot these measurements throughout the year.
Additional exercises that utilize the Mauna Loa CO2 data include:
- Modeling Atmospheric CO2 Data, from Evergreen State College (for upper high school and college)
- The Modern Atmospheric CO2 Record, from SERC (for high school and college, uses Excel)
Supplemental sites with additional information include:
- Trends in Atmospheric Carbon Dioxide - Mauna Loa, from NOAA's Earth System Research Laboratory
- Mauna Loa Carbon Dioxide Record, from NOAA's Top Ten Foundation Data Sets
- Intergovernmental Panel on Climate Change (IPCC) report, from the World Meteorological Organization (WMO) and United National Environment Programme (UNEP).