Communications Booster: Carbon Cycle and Carbon Reservoirs
Alberto Ramirez, Frederick Community College, Frederick (MD)
Elisabeth Harthcock, San Jacinto College, Pasadena (TX)
Laura Rico-Beck, Museum of Science and Industry, Chicago (IL)
These materials were created by faculty as part of the CLEAN Climate Communications Workshop, held in April, 2012 and are not yet part of the CLEAN collection of reviewed resources. This activity is part of the community collection of teaching materials on climate and energy topics.
Activity Summary: In order to understand the causes of present-day climate change, students must be familiar with carbon cycle and the trends in atmospheric carbon dioxide. Through this activity, students will use authentic scientific data to construct their own understanding of the atmospheric processes that influence the carbon dioxide record. Additionally to using data, students will acquire a conceptual framework to understand the challenges of climate change.
Activity Description: This is a two-step activity involving the carbon cycle. The first (Carbon Cycle: A Jigsaw Approach) focuses on the intricacies of the organic components of the cycle, and the second (Carbon Cycle Toolkit) focuses on available scientific data and modeling. Both steps emphasize collaboration and critical thinking.
Original Activities from the CLEAN Reviewed Collection
- Carbon Cycle: A Jigsaw Approach by David Hastings, Eckerd College, from the On the Cutting Edge activity collection
- Carbon Cycle Toolkit from NOAA/Earth System Research Laboratory
Learning Goals
Key Learning Outcomes
For Carbon Cycle: A Jigsaw Approach, students will:
- understand where photosynthesis occurs on the planet
- explain how CO2 is generated through the respiratory process
- describe how food webs work, and how carbon flows through them
- understand how the death of organisms is part of the carbon cycle
- explore how decomposition takes place in terrestrial and aquatic environments
- describe how the above processes interact and determine the flow of carbon in the organic portion of the carbon cycle.
- demonstrate the ability to interpret graphs and quantify the amount of CO2 in the atmosphere
- analyze and compare scientific data, identify short- and long-term trends in the data, and determine which natural processes and activities can be attributed to the resulting data.
- identify the potential implications of the scientific data on natural ecosystems and human society
- evaluate common misconceptions about the carbon cycle and generate explanations to correct the misconceptions using scientific data and an understanding of natural processes.
Climate Literacy Context
- Climate Principle 2: Climate is regulated by complex interactions among components of the Earth systems (2.c, 2.d)
- Climate Principle 3: Life on Earth depends on, is shaped by, and affects climate (3.e)
- Climate Principle 4:Climate varies over space and time through both natural and human-made processes (4.f, 4.g)
- Climate Principle 5: Our understanding of the climate system is improved through observations, theoretical studies, and modeling (5.b)
Instructional Strategies
- Project-based problem solving as in a Jigsaw Approach.
- Assignments to specific roles and tasks to students organized in teams.
- Exploration and treasure-hunt activities using Google Earth.
- Field activities such as estimating vegetation coverage in your neighborhood, school area or selected park.
- Experimental activities using class aquarium, terrarium or simple microorganism culture to measure respiration and CO2 production.
- Experimental activities involving the correlation between CO2 solubility and temperature.
- Moderated discussions, both face-to-face and online, to follow up on each of the five carbon cycle processes.
- The activities are structured around student involvement. The instructor is a lecturer at first but quickly shifts into a facilitator role, ensuring that there is a fundamental understanding of the carbon cycle.
- The activities also use an experiential learning strategy as students gather and analyze data, diagram and summarize results, and evaluate and explain their conclusions.
Misconceptions and Potential Pitfalls
Misconceptions and Potential Pitfalls for Carbon Cycle: A Jigsaw Approach,possible misconceptions include:- natural cycles include periodic increases in CO2 and the carbon cycle has regulated them in the past
- nature has its way to "fix things"
- the ocean has an almost infinite capacity to absorb CO2 and carbon, so the ocean reservoir can reduce any increase in CO2 concentration.
- if we increase agricultural and forestry development, we can capture more CO2 and help balance the carbon cycle.
These misconceptions try to exempt or justify human activities in the equation, and the activity proposed is geared towards awareness of individual and collective responsibility.
TheCarbon Cycle Toolkit is an effective way to address the following 3 misconceptions:- The atmosphere is big and CO2 makes up a small percentage of the total gases, so we are not adding enough carbon dioxide to make a difference. A strategy to address this misconception:
- Show students the graph to the right.
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- Ask students to make a claims and evidence T-chart and write as many claims as they can based on what they observe in the graph. A claim/evidence pair may be temperature changes and CO2 changes are closely aligned/the blue and red lines in the graph show the same general trends.
- Introduce the misconception and discuss why the statement is incorrect. Although CO2 is not very abundant in the atmosphere, the fact that it is a greenhouse gas makes it able to trap heat very effectively, and even in small amounts it has large effects on the temperature of the atmosphere.
- NOTE: introduce the misconception only after students have carried out the claims and evidence chart in order to avoid the familiarity backfire effect.
- Show students the graph to the right.
- Burning fossil fuels uses them up, leaving nothing behind. A strategy to address this misconception:
- Place a piece of paper, cotton ball, or other flammable material in a clear glass beaker.
- As a class, encourage students to come up with the chemical formula for the material.
- Write the formula on the board.
- Light the material on fire and ask students to observe what happens.
- As a class, brainstorm the products of the reaction and write the complete balanced molecular equation on the board.
- Explain that combustion is a chemical process that obeys the Law of Conservation of Matter and matter cannot disappear. If we burn something like fossil fuels, the carbon stored in plants and fossilized into coal and oil does not disappear when it burns, but rather it is transformed into the invisible and colorless CO2 and water.
- Humans' addition of CO2 to the atmosphere is increasing the total amount of carbon in the environment. This might throw the carbon budget cycle off balance, impacting the carbon cycle. A strategy to address this misconception:
- Show students the following image, and ask them why it is incomplete:
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- After they identify the processes of the carbon cycle that are missing from the image, show them this image:
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- With these images in mind, introduce them to the misconception and ask them if they can identify why this statement is incorrect. Lead students to the understanding that human activities have the effect of transferring carbon stored in plants and fossil fuels to the atmosphere. The amount of carbon in the atmosphere (and also in the oceans) is increasing, but the total amount of carbon on Earth remains the same.
- Show students the following image, and ask them why it is incomplete:
Potential Pitfalls:
- Due to the intrinsic interdisciplinarity characteristic of climate change the jargon might be an obstacle. Vocabulary worksheets are a good way to address this issue.
- When working with time series, students may not fully understand time scales, dimensions, averages and trends. Pre-assess whether you need to go over these concepts before the activities begin.
- Basic geographic concepts such as latitude, altitude, insolation, seasons, land versus ocean coverage, etc. may need to be refreshed.
- Since CO2 is colorless and odorless, the presence of CO2 in the atmosphere might be an abstract concept. Additionally, the different processes by which carbon travels through the carbon cycle may be new or poorly understood. See the above experiment and the supplemental materials to address this issue.
Supplemental Materials
Supplemental Materials from CLEAN
- Resources included in the Understanding the Carbon Cycle: A Jigsaw Approach
- Resources included in the Carbon Cycle Toolkit
-
Carbon cycle interactive animation including embedded videos and captioned images
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The Carbon Cycle- a narrated and animated carbon cycle visualization
- Climate Change: Eye on the Oceans: http://www.irinnews.org/Report/95245/CLIMATE-CHANGE-Eye-on-the-oceans
- CO2 Now: What the World Needs to Watch (student favorite): http://co2now.org
- Ocean Acidification: The Other CO2 Problem: https://www.nrdc.org/sites/default/files/NRDC-OceanAcidFSWeb.pdf
- NOAA's Trends in Atmospheric Carbon Dioxide is an excellent source of up to date data: http://www.esrl.noaa.gov/gmd/ccgg/trends/
- A Sea Change: award-winning documentary about CO2 and ocean acidification; it goes to the root of the carbon cycle in the ocean and how it's been disrupted: http://www.aseachange.net/about.htm
- The Carbon Cycle, The Ocean, and the Iron Hypothesis. Can we affect the CO2 cycle by fertilizing the ocean? This site explores the hypothesis of the importance of iron in ocean photosynthesis: [https://web.archive.org/web/20160511113614/http://oceanworld.tamu.edu/resources/oceanography-book/carboncycle.htm]