Global Warming and Carbon Dioxide Sequestration
From FUTURESTATES collection, lesson plan 7 of 13
Audience: Grade 9 Biology; Grades 10-12 Advanced, AP, or Dual-Credit Biology; Environmental Science. This lesson is designed to follow instruction in Ecology and ecological cycles and requires familiarity with the concepts of global warming and climate change. Knowledge of photosynthesis and genetic transfer are also recommended.
Duration: Each lesson is designed for a 45-55 minute class period. The modules may be separated or combined to accommodate differences in instructional time. The entire unit may be completed in 3 days, but may also be extended to include additional activities or to provide additional time where needed (see Extension Activities).
Overview of Mr. Green: In this parable about climate change, a jaded government undersecretary becomes the unwitting test subject in an experimental program to curb global warming.
Summary of the Lesson: In this lesson, students will analyze selected data that supports global warming, watch the film Mr. Green, analyze the validity of the solution presented in the film, and investigate the concept of carbon dioxide sequestration.
National Educational Standards: All components are aligned to the National Science Education Standards as presented by the National Academy of Science and available as a free download.
NS.9-12.3 LIFE SCIENCE
As a result of their activities in grades 9-12, all students should develop understanding of:
- The cell
- Molecular basis of heredity
- Biological evolution
- Interdependence of organisms
- Matter, energy, and organization in living systems
NS.9-12.5 SCIENCE AND TECHNOLOGY
As a result of activities in grades 9-12, all students should develop:
- Abilities of technological design
- Understandings about science and technology
NS.9-12.6 PERSONAL AND SOCIAL PERSPECTIVES
As a result of activities in grades 9-12, all students should develop understanding of:
- Environmental quality
- Natural and human-induced hazards
- Science and technology in local, national, and global challenges
In addition to the National Standards for Science, the lesson plans provide an excellent framework for instruction in Media Literacy. This instruction further supports both NS.9-12.1 SCIENCE AS INQUIRY and NS.9-12.7 HISTORY AND NATURE OF SCIENCE by instructing students in methods that will make them more effective in media analysis. Information on Media Literacy can be found at NAMLE.net.
Background Brief: This is information for the teacher. It includes information that may help you help your students understand the underlying science in the film.
The Problem of Excess Carbon Dioxide
Since the beginning of the Industrial Revolution, the levels of atmospheric carbon dioxide have risen. The resulting increase in CO2 is contributing to a rise in the average temperature of the planet. This change in global temperature, often referred to as “global warming,” is linked to many apparent widespread changes in our climate. Examples of these changes include greater storm intensity; increased drought, flooding, and wildfires; shifts in seasons; and more severe heat waves.
How Did This Happen?
The most commonly stated reason for global warming is the excessive burning of fossil fuels like coal, oil, and natural gas. The carbon within these fuels has been locked inside the original plant material for millions of years. Burning these products releases carbon from deep within the Earth into the atmosphere at an accelerated rate. While the ocean, soil, and plants have always acted as gigantic carbon “sinks,” absorbing excess carbon dioxide from the air, the rate and amount of carbon dioxide released by the burning of fossil fuels is overwhelming the cycle, leading to a buildup of CO2 levels in the atmosphere.
What About the Trees?
The soils and land-based plants of the world are collectively the world’s largest carbon sink. Through the process of photosynthesis, the trees and other plants are able to take in carbon dioxide gas and “tie it up” in the form of glucose as part of the biomass of the plant. Although plants do release some carbon dioxide as a waste gas during respiration, they sequester much more during the process of photosynthesis. However, deforestation has greatly reduced the number of forests on the planet. Also, rising temperatures and decreased rainfall have affected the efficiency of photosynthesis for many plants.
Is there such a thing as an organism that can be both photosynthetic (autotrophic) and heterotrophic? The protist known as Euglena is. In fact, the Endosymbiont Theory implies that in the past, many organisms were able to accomplish this feat. The chloroplast, which is the photosynthetic “machine,” has its own genome. If you needed to isolate the gene for a chloroplast, you could find it in the plastid itself.
Genetic Engineering/Gene Transfer
Although certainly not likely to happen any time soon, the idea of genetically altering a human to express chloroplasts in the skin does deserve some consideration. If the chloroplast genome and its controls could be isolated, if there were vectors that could deliver it (such as pollen grains or viral particles), and if the host could avoid being harmed by the products of the chloroplast (glucose), then such a gene transfer might be possible. If the transfer worked, it could result in a planet of organisms with a combined carbon footprint of zero. Such a scenario might not reverse global warming, but it could potentially halt further warming.
In 1998, the Precautionary Principle was presented as a proposed basis for future environmental and public health policy. In effect, it stated that when the health of humans or the environment was at stake, it was not always necessary to wait for scientific proof before taking protective actions. In other words, it followed the old adage “it is better to be safe than sorry.” The Precautionary Principle is based on the ethical assumption that humans have the responsibility to protect, preserve, and restore the global ecosystem. It also puts the burden of proof that the action is harmless on those taking the action. Future development and cultivation of agricultural GMOs may be approved or prohibited based on this policy.
Commercial Production and Identification of GMOs
Additional information is available in most advanced biology textbooks.
Curricula Writer: A 23 year veteran of teaching, Kathie L. Hilbert is currently the Science Chair at Connersville High School in Connersville, Indiana. Ms. Hilbert has both a BA (University of Evansville) and MAT (Miami of Ohio) in Biology. Ms. Hilbert has taught all levels of Biology and Earth Science, as well as Botany and Geology. She has also accompanied and supported her students on several summer Marine Biology programs held in Hawaii. Ms. Hilbert has written and developed curriculum for Botany, Geology, and Early College Earth Science as well as revised curriculum for other classes. She has also written curriculum for community Science Outreach Programs and was a Science Ambassador for the CDC (writing lesson plans for their website). Ms. Hilbert was Fayette County’s Teacher of the Year in 2001 when she also successfully attained National Board Certification in science teaching.
Objectives: Students will:
- Differentiate between the terms “global warming” and “climate change.”
- Discuss some of the issues associated with excess carbon dioxide in the atmosphere.
- Analyze data from three different sources to answer the following question: “Do we have any evidence to support or refute the proposition that the level of carbon dioxide in our atmosphere is increasing?”
- Worksheet 1 (see page 8)
- Worksheet 2 (see page 10)
- Graph paper
Beginning (5-7 minutes)
Whole class discussion. The teacher should write the terms “Global Warming,” “Climate Change,” and “Something Else” on the board. The teacher will begin by asking students to place the term “Greenhouse Effect” under the correct heading(s). The teacher will continue this procedure with similar terms in an attempt to determine prior knowledge and to highlight misconceptions. Terms to include: ozone, CFCs, fossil fuels, humans, ocean, carbon dioxide, solar radiation, natural, unnatural, etc. When the list is finished, the teacher and students will discuss each choice and correct any misconceptions. Discussion ends with the question: “Do we have any evidence to support or refute the proposition that the level of carbon dioxide in our atmosphere is increasing?”
Middle (30 minutes)
The class will investigate ice core sample analysis data and data on atmospheric carbon dioxide levels (see Worksheet 1 and Worksheet 2 in supplemental materials). Organize students in groups of 4. Each group will organize and analyze data from both data sets. Two students will work on the ice core data, and the other two will analyze the atmospheric carbon dioxide data. Upon completion of their assignment, the teams will meet in their group to discuss their findings. When all groups are finished, the instructor will lead the class in a discussion and clarification of the findings. The work of both teams will be counted toward a single grade for the group.
End (10 minutes)
Return to the original question: “Do we have any evidence to support or refute the proposition that the level of carbon dioxide in our atmosphere is increasing?” Conclude with a brief discussion of class consensus. “What can we do about it?” Tomorrow we will look at one possible answer.
- Responses during the introductory discussion and final discussion.
- Accurate completion and interpretation of group data activity.
Objectives: The students will:
- View the Mr. Green film
- Discuss the basic premise of film
- Analyze the science behind the premise of the film
- Evaluate the impact of photosynthetic humans on excess carbon dioxide levels
* Computer/internet access for viewing film
Beginning (10 minutes)
Remind students of data from the previous lesson. Ask: “Do we have any evidence to support or refute the proposition that the level of carbon dioxide in our atmosphere is increasing?” Discussion should lead to an affirmative answer. The instructor then asks, “What can we do about it?” The teacher and the students discuss some possible answers. The teacher asks students to consider the terms “carbon footprint” and “going green.” The teacher may use examples from media to facilitate the discussion. The teacher then asks students, “Are we trying to reduce the amount of carbon dioxide we release into the atmosphere or are we trying to reduce the levels already present?” Students briefly discuss the statement, supporting their answer. The teacher then introduces the film by saying, “The film we are about to see presents an imaginative approach to reducing the carbon footprint of every human to zero.”
Middle (30 minutes)
View Mr. Green.
Upon completion of the film, discuss the students’ impressions of the film. It is likely that students will not find the solution presented in the film realistic or plausible. The teacher should use the following questions, which encourage students to think “outside the box.”
- Do we know of any creature in nature that can be both autotrophic and heterotrophic? (Example: Euglenoids.)
- What does the Endosymbiont Theory imply?
- Do you have to have roots and leaves to be photosynthetic? What do you need?
- From a biotech standpoint, what would you have to isolate and transfer to create a photosynthetic human?
- In the film, is the transfer an infection or an actual gene transfer or both?
- Are there any repercussions to the development of photosynthetic humans, as presented in the film?
- Why was this film made?
End (5-7 minutes)
Wrap up the discussion and summarize major points. Students are the asked to respond to the writing prompt: “What if the transfer of chloroplasts to humans could be accomplished? Would it eliminate the human carbon footprint? If it did, would that be a good thing?”
Note: If the teacher wishes to complete the writing assignment in class, discussion time may be adjusted as needed.
- Classroom discussion
- Response paper
Objectives: The student will:
- Investigate methods of carbon dioxide sequestration.
- Evaluate the effects of sequestration on reducing carbon dioxide in the atmosphere.
- Worksheet 3: Carbon Sequestration (see page 12)
- Ticket Out Worksheet (see page 13)
- Access to computer for website information
Beginning (5-7 minutes)
Review the major points of the film and the previous day’s discussions. Ask students: “What can we do now? The film mentions carbon dioxide sequestration. What is it? Is it a viable answer to the problem of excess carbon dioxide in our atmosphere? Just because we can do it, should we? Today we will look at the feasibility of carbon dioxide sequestration.”
Middle (30 minutes)
Students will investigate carbon dioxide sequestration. Go to: www.ccs-education.net and watch the CCS film. Using the Overview on the website and information from the film, students will complete the worksheet on carbon dioxide sequestration (Worksheet 3).
End (10-12 minutes)
Teacher will give a final verbal overview of topic. Students will complete a “Ticket Out” concerning what they have learned (see supplemental materials).
Assessment * Accurate completion of the Carbon Dioxide Sequestration worksheet * Responses to Ticket Out questions
To save time, the teacher could use just the ice core data activity. It provides the information that links increased carbon dioxide levels to an increase in global temperatures. If the goal is to introduce students to the debate over global warming, excerpts from the film An Inconvenient Truth could be shown along with the IZZIT film Unstoppable Solar Cycles, which is available for free to teachers at www.izzit.org. The films present two opposing viewpoints and will encourage students to consider both sides of the argument.
If time is an issue for the teacher, Mr. Green could be used as enrichment to support instruction in climate change. It can also be paired with the FUTURESTATES film Seed as enrichment to accompany a unit on biotechnology, and/or paired with the FUTURESTATES film Rise to further explore the possible repercussions of climate change.
If time is short, this lesson can be foregone. In its place, the teacher may ask students to research other ways of reducing excess carbon dioxide in our atmosphere. The focus could be on renewable resources and energy efficiency. For more information: