Type your answers in the space provided after each numbered question.

  1. According to the following website, how much CO2 did the United States emit in 2019?

__________ million metric tons

  1. Convert this answer to short tons, which is the unit used in the United States. Here is a link to a conversion calculator:

__________million US tons

  1. The World Economic Forum website has a graph showing the carbon footprints of 12 countries. The graph compares CO2 emissions per capita (per person): .  According to this graph, what is the average carbon footprint for people living in the United States?


Use the EPA website to answer the following questions about your carbon footprint.

  1. Current Emissions from Home Energy: Fill in the requested information at the top portion of the Home Energy section.  Ignore the lower portion of that page (Reduce Your Emissions section).  Add up your totals (in the green boxes).  What is the estimated amount of CO2 in pounds (lbs.) per year that your household emits?


  1. Current Emissions from Transportation: Scroll down and continue to Transportation. Fill in the requested information at the top portion of the Transportation section only.  What is your total estimated CO2 emission in pounds (lbs.) per year for transportation?



  1. Current Emissions from Waste: Scroll down and continue to the section on Waste. Just fill out the top portion.  What is your total estimated CO2 emission in pounds (lbs.) per year for waste?


  1. Your Household Carbon Footprint Report: Scroll down and select continue to report.  What is your carbon footprint in estimated CO2 emission in pounds (lbs.) per year?


  1. How does your carbon footprint compare with the national average? Describe how your carbon footprint differs from the national average.  Which category is similar, which is different and by how much?


  1. Now go back to the beginning and complete the bottom section for Home Energy, Transportation and Waste to see how much an impact changes in lifestyle could make. What modification to your lifestyle makes the largest impact and how much in terms of gallons of gasoline and trees planted do your modifications translate into?


Save your Carbon Footprint Report.  Save your report by selecting the print/save option and printing the report as a pdf.  You will need to submit that file along with this completed lab to receive credit for this assignment.

  1. Do you think the results of your carbon footprint would be much different if airplane travel were included? Why or why not?


Carbon Neutrality

To avoid the worst-case scenario of global warming, nations need to become carbon neutral by 2050.  This means that the amount of CO2 released into the atmosphere will be equal to the amount of CO2 that is absorbed by carbon sinks (like trees, the ocean, etc.), and the NET carbon footprint is zero.  This will require a number of different solutions.  One that seems to be very popular is donating money to organizations to plant trees.  So let’s consider whether or not this is an effective way to sequester (store) carbon dioxide that results from the lifestyle of an individual living in the United States.

  1. Young trees absorb about 13 pounds (lbs.) of CO2 per year, while mature hardwood trees absorb about 48 lbs. per year. Let’s use the average of these two numbers to estimate the amount of CO2 per year that can be stored by one tree: 30 lbs.

If one tree can absorb and store 30 lbs. of CO2 in one year, how many trees would it take to absorb your carbon footprint this year?



  1. Now consider how much land is required to plant enough trees to absorb and store your carbon footprint for one year. One acre of new forest can sequester (store) 2.5 tons of CO2.  An acre is about the size of a football field.  To figure this out you need to convert your carbon footprint from pounds (lbs.) to tons (US).  One US short ton is equal to 2,000 pounds.

Here is a conversion calculator:[short,+US]

If one acre can sequester 2.5 tons of CO2, how many acres of forest would be needed to absorb your carbon footprint?


  1. This number of acres of new forest doesn’t really sound like a lot, but let’s now consider this for the entire population of the United States. Households in the United States emit about 4 billion tons CO2 (1 billion tons = 1 gigaton).   If 1 acre of forest can absorb 2.5 tons CO2, then roughly 2.16 billion acres of land would need to be planted in trees to absorb America’s carbon footprint.

Now convert that estimate of acreage to square miles so you can see how much land would be needed.  There are 640 acres in one square mile.  Divide 2.16 billion acres above by 640.  This will tell you how many square miles of newly planted forest are needed to sequester 5.4 gigatons of carbon dioxide.  Write your answer here:


  1. Use the CIA World Factbook to find the country that has about this land area:

What country in the world is approximately the size of land that would need to be planted in forest to absorb America’s carbon footprint?

  1. Based on these calculations, do you think tree planting is a practical solution for sequestering atmospheric carbon to reduce CO2 levels and prevent the worst-case scenarios of climate change? Explain your answer for credit.


  1. Look up Afforestation in Drawdown. According to the essay on this topic, how many gigatons of carbon could be sequestered by tree planting in 2030?  Briefly, discuss the appeal and the limitations of Afforestation as a strategy to reduce the level of atmospheric CO2.
Carbon Footprint Activity