In this activity, students will collect data on atmospheric carbon dioxide levels for 48 hours using a carbon dioxide sensor, then graph the data to see how the levels vary during different times of the day.
Students will learn about the carbon cycle, photosynthesis, and levels of carbon dioxide in the air.
This straightforward activity will show students the important role that plants play in the carbon cycle.
The PDF offers helpful explanations for how photosynthesis affects carbon dioxide levels, as well as an informative diagram of the fast carbon cycle.
Teachers will need carbon dioxide sensors and graph paper for this activity.
It takes 48 hours to collect the data, so teachers should plan accordingly.
The link for the U.S. Naval Observatory data does not work.
Before the activity, teachers could ask students to discuss the following questions in pairs or small groups:
What part do plants play in the carbon cycle?
How do you think photosynthesis affects carbon dioxide levels in the atmosphere?
Do you think that atmospheric carbon dioxide levels vary at different times of the day? If so, why?
Biology classes could use this experiment to explore the differences between CAM, C3, and C4 plants and discuss what evolutionary benefits each type of plant has that affects the concentration of carbon dioxide in the air surrounding these plants at different times.
As an extension, students could collect data on the carbon dioxide levels in two locations, one with lots of vegetation and another with no vegetation (e.g. a large parking lot) to see if the carbon dioxide levels vary throughout the day in the same way in both locations.
This resource provides insights into the variation of temperature and CO2, including the chemical reaction and processes in the carbon cycle in the earth-atmosphere-ocean system. This is recommended for teaching.
ESS2: Earth's Systems
7.ESS2.1 Develop a model to describe the cycling of Earth’s materials and the flow of energy that drives this process.
HS.ESS2.6 Develop a quantitative model to describe the cycling of carbon among the hydrosphere, atmosphere, geosphere, and biosphere.
LS1: From Molecules to Organisms: Structures and Processes
7.LS1.6 Construct a scientific explanation based on evidence for the role of photosynthesis in the cycling of matter and flow of energy into and out of organisms.
LS2: Ecosystems: Interactions, Energy, and Dynamics
7.LS2.3 Develop a model to describe the cycling of matter and flow of energy among living and nonliving parts of an ecosystem.
HS.LS2.5 Develop a model to illustrate the role of photosynthesis and cellular respiration in the cycling of carbon among the biosphere, atmosphere, hydrosphere, and geosphere.