Stimulating Understanding of Computational science through Collaboration, Exploration, Experiment, and Discovery for students with Hearing Impairments
How to weight a tree
Weighing a tree
Calculating the CO2 sequestered in a tree
Comparing the CO2
produced by a family or school to the CO2 sequestered in a tree.
How to weigh a tree
Pick a tree at school or in the community that the students will see on a regular basis. When they see the tree they will think about the CO2 they are putting into the atmosphere. After you have picked a tree you need to identify its species. There are a number of fine identification keys available on the web (see "Resources").
Use a string and ruler to measure the circumference of your tree at chest height. If your tree is on a hill stand on the uphill side of the tree. Pace off a convenient distance from the tree (50 - 100 ft). Hold a ruler vertically at arms length. Line up the bottom of the ruler with the base of the tree. Using the ruler measure the apparent height of the tree. Measure the distance from your eye to the ruler.
How to calculate the CO2 sequestered in a tree
Comparing the CO2
produced by a family or school to the CO2 sequestered in a tree
The average household drives 20,895 miles per year. Calculate the number of trees needed to sequester the CO2
produced by a family driving different kinds of cars. How much CO2 is produced by your school buses each month? How much CO2 is produced by teachers and students driving to school each month? How many trees is this equivalent to?
On average electricity production in the U.S. produces 1.64 pounds of CO2/kWh. Find the number of kilowatt hours that the power plant can produce when it produces the amount of CO2 your tree has sequestered. Count the light bulbs in your class. Determine the kWh of electricity used by these lights each month. How many classes are there in your school? What is the electrical use of your school each month? How many months worth of CO2 is sequestered in your tree?
Natural gas produces .12 pounds of CO2/ft3. Fuel oil produces 22.29 lbs of CO2/gal. How many pounds of CO2 are produced to heat your school each month or for the winter months?
How many trees worth of CO2 is your school responsible for producing each month? Each year? How much area does your tree take up? How much of the football field would you have to plant in trees each year to sequester the CO2 your school produces?
calculator (pocket or Excel), MPG for different vehicles (EPA is a good source see "Resources"), school's energy use (electrical, natural gas, heating oil, school bus fuel, check with principal and or central office).
Which tree weight did you use, above ground, roots, or total weight? Why did you pick that one over a different weight? The green weight includes the leaves. They fall off each year and turn back into CO2. We don't have enough information to decide how to deal with these issues. The lesson „Forests, Mining Carbon from the Airš uses a professional model to explore carbon as it moves through a forest, its products and the atmosphere.
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