Purpose: When it comes to fighting global warming, it’s hard to know where to start. How can individuals make meaningful contributions to this effort? This activity, designed for in-class or at-home learning, encourages students to find ways they can reduce their own carbon footprints, as well as help others work toward the same goal.

Procedural overview: After reading and discussing the online article “What lifestyle changes will shrink your carbon footprint the most?” in groups, each student will calculate their household carbon footprints and identify ways to reduce that footprint. Then, students will discuss and compare their data with data from the class. The groups will use the shared data to develop a plan for reducing the carbon footprints of their communities.

Approximate class time: 1 class period

Supplies:

Calculator
Computer with internet access
Virtual space (for discussions and sharing data remotely)
“Starting Small to Curb Climate Change” student worksheet

Directions for teachers:

Place students into groups and introduce the activity’s purpose and procedure. If students will be doing this activity virtually, instruct them on the platform they should use for discussion (Zoom, Skype or another suitable chat program) and for data sharing (e-mail, Google Docs, Sheets or Slides).

Instruct students to read the article “What lifestyle changes will shrink your carbon footprint the most?” and discuss with their group what they learned about the lifestyle choices that affect the carbon footprints of individuals, households and communities. Student discussions should include how specific factors compare in terms of the amount of emissions created or saved, based on the graphics in the article.

Student background questions No. 1 through 9 (below) lead student groups through an analysis of the graphics.

Your carbon footprint

After reading and discussing the article, students will use the Environmental Protection Agency’s carbon footprint calculator (https://www3.epa.gov/carbon-footprint-calculator/) to determine their household’s current yearly carbon footprint. Students will then review the options for reducing emissions in each category (energy, transportation and waste) and determine which approaches are reasonable and affordable for their family to make. Students will determine the emissions savings if they make these changes in their households.

Questions No. 10 through 26 (below) will guide students as they calculate and interpret their carbon footprint data. Students may have to ask an adult to help with some of the estimates, such as monthly bills.

Community reduction plan

Students will next share their data with the teacher, who will compile the data to share with the class. Ask students to submit their pounds of carbon dioxide equivalent emissions for home energy, transportation, waste and the combined total — along with their proposed changes and the accompanying emissions savings. Compile the data anonymously in a spreadsheet, and give the class averages for total emissions, home energy emissions, transportation emissions and waste emissions. You should also provide an average emissions savings for each of the lifestyle changes that students proposed (and indicate the number of people who proposed that change). Share the full spreadsheet with the class.

After reviewing the class data, student groups can discuss and compare the pros and cons of any promising solutions. Based on the discussion, student groups will identify reasonable ways their community can reduce its carbon footprint and formulate an action plan for communicating and implementing these changes. Student groups will also consider whether similar actions might or might not be successful elsewhere in the world.

Questions No. 27 through 37 (below) will guide students through the formulation of their action plans and discussions of how these plans could be implemented.

Activity extension

As an extension, students can consider the effects that large-scale events such as pandemics, volcanic eruptions, large wildfires or wars can have on carbon dioxide and other greenhouse gas emissions. Students should be encouraged to find data and visuals (such as those taken from space during the 2019–2020 Australian wildfires, or during the COVID-19 pandemic, including over Europe, China and the United States). Have students examine the images for how emissions change over time before, during and after these events, as well as how the results can affect neighboring countries and the world. Students should be sure to consider the trade-offs of reduced or increased emissions.

Understanding the issue

After reading the article “What lifestyle changes will shrink your carbon footprint the most?,” discuss with your group the lifestyle choices that affect an individual’s carbon footprint, as well as the footprint of a household and community. How do those factors compare in terms of their scale of emissions?

The following questions will help your group work together to interpret the graphics in the article.

1. The graphics show how lifestyle choices can affect carbon dioxide emissions. What is meant by “carbon dioxide equivalent”?

“Carbon dioxide equivalent” expresses the global warming potential of another emission in terms of the amount of carbon dioxide that would have that same warming potential. If 1 ton of methane creates the same amount of global warming as 21 million tons of carbon dioxide, then the carbon dioxide equivalent is 21 million tons.

2. What do the green circles represent in the graphics?

The tons of carbon dioxide equivalent emissions saved per year.

3. In the transportation graphic, which replacement for a 25 mpg car results in the greatest emissions savings? How many tons of carbon dioxide equivalent emissions per year are saved by making this change?

Changing to an electric car results in the greatest savings. It saves 4.4 tons of carbon dioxide equivalent emissions per year.

4. Compare the green circles for carpooling and taking the bus. Which circle represents a greater savings of carbon dioxide equivalent emissions?

The circle for carpooling represents a greater savings.

5. According to the graphic, what is the round trip distance from home to work used in the carpooling calculation?

A round trip would be 25 miles.

6. How many miles of driving alone does carpooling twice a week save, according to the graphic? How many 25-mile bus rides would cover the same distance?

Since people have a 25-mile round trip to work, carpooling with one other person twice a week saves 50 miles of driving alone per week. This would be the equivalent to taking two 25-mile bus rides.

7. Based on your answers from question 6, which saves more carbon dioxide equivalent emissions: carpooling twice a week or the equivalent distance in bus rides?

Carpooling twice a week replaces 50 miles of driving alone and saves 0.9 tons of carbon dioxide equivalent emissions. Taking the bus twice a week also replaces 50 miles of driving and saves 2 x 0.5 tons of carbon dioxide equivalent emissions, or 1 ton of carbon dioxide equivalent emissions. Taking the bus saves more.

8. When assessing the impact of individual actions, why is it important to be able to read and interpret data correctly?

It is important that people are able to read and interpret data correctly so they don’t make lifestyle choices based on a misunderstanding. For instance, at first glance, the graphics appear to say that carpooling saves more emissions, but in reality taking the bus saves more if the person is traveling the same distance.

9. Look over the graphics for emissions related to shelter and food. As a group, decide what changes might have the largest impact on emissions. Remember to review the graphics carefully to ensure you are interpreting them correctly.

Your carbon footprint

After your group discussion, use the Environmental Protection Agency’s online carbon footprint calculator (https://www3.epa.gov/carbon-footprint-calculator/) to determine your household’s carbon footprint, then answer the following questions on your own. You may have to ask an adult to help you make some of the estimates, such as the monthly bills. Start by determining what your current household’s footprint is currently, without entering any changes.

10. What are your household’s current emissions from home energy per year?

Our household’s current emissions from home energy are 20,786 pounds of carbon dioxide equivalent emissions per year.

11. Which energy source was the highest contributor to that total? What is this energy source used for?

The biggest contributor to that value is our natural gas use, which was 13,436 pounds of carbon dioxide equivalent emissions per year. We use this energy source for heating and hot water (showers, washing machine and dishwasher).

12. What are your household’s current emissions from transportation per year?

Our household’s current emissions from transportation are 25,981 pounds of carbon dioxide equivalent emissions per year.

13. What is your household’s current emissions from waste before recycling per year? How many pounds of emissions does your family save per year by recycling?

Our household’s current emissions from waste before recycling is 2,766 pounds of carbon dioxide equivalent emissions per year. We save 500 pounds of carbon dioxide equivalent emissions per year by recycling.

14. What is your household’s current emissions from waste after recycling per year?

Our household’s current emissions from waste after recycling is 2,266 pounds of carbon dioxide equivalent emissions per year.

15. What is your household’s current total carbon footprint per year? According to the calculator, is this number higher, lower or the same as the U.S. average for a household of your size in your area?

Our household’s current total carbon footprint is 49,033 pounds of carbon dioxide equivalent emissions per year. This value is lower than the U.S. average.

16. In the article, Kim Cobb says she started reducing her carbon footprint by making small changes. Do you think making small changes in your household could make a difference? Why or why not?

I think every bit helps, but overall I don’t think a single household can make a significant change. But if we all make small changes, then that can make a difference.

17. According to the article, Kim Cobb changed her diet and amount of air travel. Why do you think these are not a part of the EPA’s calculation?

I think food was left out for a lot of reasons. Dietary restrictions prevent some people from eating certain foods because of their religion or allergies. Since people eat different amounts of different foods from day to day and week to week, and the food comes from different sources, calculating carbon dioxide equivalent emissions would be really hard to do. Also, it is not clear from the graphic what people eat in a week on average, what a serving size is and the duration the savings is for, but the amounts saved seem small compared with other changes. I think flights were left out because most people do not fly very often, so this change would also be very small compared with things people do every day like drive their cars or turn on the lights. According to the graphics, you could save the same emissions by carpooling two days a week for three weeks as by canceling one round trip cross-country flight a year.

18. Go back to the Home Energy tab on the calculator and look at the ways the EPA suggests you can reduce your household’s carbon footprint from home energy use. Choose one of these suggestions that you think would make sense for your household and type in the adjustments to the calculator to adjust your footprint accordingly.

What could you change? How many pounds of carbon dioxide equivalent emissions would you save per year?

We could replace our lightbulbs with ENERGY STAR lights. If we changed 10 lightbulbs we would save 240 pounds of carbon dioxide equivalent emissions per year.

19. Why does this change make sense for your household? Does this change seem like it would be easy and affordable for your household to make?

Yes, the lightbulbs are not very expensive, and the calculator says we would also save $40 a year on electric bills by changing the bulbs.

20. Go back to the Transportation tab on the calculator and notice that the EPA suggests you can reduce your household’s carbon footprint by reducing the number of miles each vehicle drives.

Is there one way your household could reduce the number of miles driven on a regular basis? Does this change seem like it would be easy and affordable for your household to make?

We could walk to school instead of having our dad drive us. This would be easy and affordable, unless it was snowing.

21. How many miles could this change save your household each year? How many pounds of carbon dioxide equivalent emissions per year would your household save?

We could save 360 miles of driving, which is equal to 275 pounds of carbon dioxide equivalent emissions per year.

22. Go back to the Waste tab on the calculator and look at any other materials your household could recycle. Choose one or more of these suggestions that you think would make sense for your household and type in the adjustments to the calculator to adjust your footprint accordingly.

What could you change? How many pounds of carbon dioxide equivalent emissions would you save?

We could recycle newspapers and glass. If we recycled newspapers and glass, we would save 554 pounds of carbon dioxide equivalent emissions per year.

23. Does this change seem like it would be easy and affordable for your household to make?

Yes, we would need to remember not to throw these items in the trash.

24. If your household were to make all of the changes you listed, how many total pounds of carbon dioxide equivalent emissions would your household save yearly?

My household would save 1,069 pounds of carbon dioxide equivalent emissions per year.

25. If every household on your street or in your apartment building were able to make these same changes, how many pounds of carbon dioxide equivalent emissions would you save collectively?

If the 14 households on my street made the same changes, we would save 14,966 pounds of carbon dioxide equivalent emissions per year.

26. How does this amount saved compare with the U.S. average for households of your size in your area?

The U.S. average for a household of my size in our area is 59,105 pounds of carbon dioxide equivalent emissions per year. The amount saved would be equivalent to about 25% of a household’s emissions.

You will now turn in your carbon footprint and emissions savings data to your teacher.

Community reduction plan

Your teacher will provide you with your class’s carbon footprint data, as well as data on proposed lifestyle changes and emissions savings. Discuss the results with your group, including the ways you think households could reduce their carbon footprints and what made these changes easy and affordable. Be sure to review the data on how much carbon dioxide equivalent emissions could be lowered if all of the households in the same apartment building or on the same street made the same changes.

Once your group has reviewed the data, you will create a plan for how your community could reduce its carbon footprint. Your plan will need to clearly outline the reasons why your changes will help reduce the community’s carbon footprint and why this is beneficial. It is important to remember that people like to know the benefits of changes before making them. You may want to research how carbon dioxide and other emissions affect global warming, what effects global warming has on the planet and how reducing our carbon footprints can help reduce global warming. Brainstorm reasons why these changes have other benefits for the community as well, such as decreasing garbage overflow that leads to litter in the park, or increasing exercise or socialization for citizens. Lastly, you will need to describe your plan for how to communicate and implement these changes.

The following questions will help your team brainstorm your plans for lowering the community’s carbon footprint.

27. Everyone in your class selected different changes for their households. Which of the changes seemed to be the easiest to make? Why?

Replacing the lightbulbs seemed to be the easiest change to make because you only have to do it once and then you are done for the life of the lightbulb, which is several years.

28. Which of the changes were the most affordable? Why?

Lowering the thermostat at night was the most affordable because it is free.

29. Which of the changes made the largest impact?

Adjusting the thermostats made the largest impact.

30. Based on the data and your answers to questions 27 through 29, what are three changes your group thinks your community could make that would be easiest and most affordable, while making the biggest impact?

Increasing recycling, replacing lightbulbs and reducing the temperature of the thermostats at night in winter.

31. Will your changes require your community to provide any additional products or services (such as recycling receptacles or recycling pickup in residential areas)? What products or services will the individual households be responsible for?

Our changes will require the community to provide recycling receptacles in public areas. Individual households will be responsible for their own recycling receptacles, their own lightbulbs and adjusting their own thermostats.

32. What are the benefits of your plan for the planet?

Our plan will reduce emissions of carbon dioxide and other greenhouse gases, so it will help reduce global warming.

33. In the article, Kim Cobb mentions that the changes she made also had a positive impact on her physical and mental well-being. Consider your changes. What personal benefits could each change have for members of the community?

Providing alternative receptacles for recycling will reduce trash in trash cans in public places. This can help reduce the overflow trash in the trash cans in our parks, which frequently ends up in the pond. This will make the park cleaner and a nicer place for people to visit.

34. According to the article, “social influence can drive change.” What three actions could your group take to help inspire your community to take action?

We could place recycling receptacles in our local park, and take the cans to a recycling center. We could have a bake sale to raise money to replace all of the lightbulbs in our school with energy-efficient lightbulbs. We could set a goal for the community and post information to let people in the community know how we are progressing toward that goal, and we could have a community celebration if our goal was met.

35. How will you communicate your plan to the community? What information will you include in your communication?

We would let people know by flyers that we wanted to reduce our carbon footprint. We would include how carbon dioxide and other emissions affect the environment, how much our proposed changes would reduce emissions, how these changes would benefit people on a personal level and about our party that we are planning if our goal is met.

36. Why might some changes that work in your household not work elsewhere in your community?

Hospitals, the elderly and childcare facilities may not be able to change their thermostats because these groups may require heating in the winter for safety reasons.

37. What are some reasons your plan may not work in every community globally?

Some people don’t have electricity to reduce or access to public recycling facilities. Also, some people may reuse items instead of recycling, which might be even better for the environment.

Bonus activity

As a bonus activity, consider the effects that large-scale events such as pandemics, volcanic eruptions, large wildfires or wars can have on carbon dioxide and other greenhouse gas emissions. You can find data online about emissions during these types of events, as well as satellite images that show how the 2019–2020 Australian Wildfires and the COVID-19 pandemic affected emissions (including in Europe, China and the United States). Be sure to consider how emissions patterns changed before, during and after these events, as well as how the results can affect neighboring countries and the world. Be sure to consider the trade-offs of reduced or increased emissions. For instance, while emissions appear to have decreased during the early stages of the COVID-19 pandemic, the amount of medical waste increased and the loss of life was tremendous.

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