Countries by carbon dioxide emissions (blue the highest)
Worldwide, the average carbon dioxide emissions per capita are about 6 tons per year.
In the U.S, the per capita average is much higher, around 20 tons per year, which resumes to 109 lbs per capita and per day.
Of those 20 tons, 12 tons come from commercial and industrial sources.
The remaining 8 tons come from individual energy usage, namely transportation and home energy use.
That means that individual energy usage in the U.S. is higher than the 6-ton average encompassing personal, commercial and industrial uses worldwide!
Carbon Calculation (Americanforests.org):
Trees’ Carbon Sequestration
The first step in determining how much carbon is sequestered by a single tree is to convert carbon to carbon dioxide (CO2) or carbon dioxide equivalent (CO2e). For our calculations, we used the common conversion of:
1 ton of carbon = 3.666 tons of CO2
This represents the weight of carbon dioxide (44) divided by the atomic mass of carbon (12). Next, it is estimated that one acre of trees stores 50.8 metric tons of carbon, so…
50.8 metric tons of carbon X 3.666 tons of CO2 = ~186 metric tons of CO2 per acre of forest
Since we don’t use metric tons as a common measurement in the U.S., we next need to convert tons to pounds:
1 metric ton = 2204.62262 pounds
186 metric tons X 2204.62262 pounds = ~410,060 pounds of CO2 sequestered per acre of trees
American Forests has estimated that our tree planting projects average 450 trees per acre, which leaves us with one final calculation:
410060 pounds of CO2/450 trees per acre = ~911 pounds of CO2 sequestered per tree planted
As you may be able to surmise from the above, to get this calculation, we did need to make a few assumptions. For instance, we choose 55 years as the age for estimating carbon sequestration and storage, and we started with the U.S. Forest Service’s averages for carbon stored by trees (58.8 tons per acre) and made slight alterations for significant outliners, which gave us 50.8 metric tons per acre. Additional sources include, the United States Department of Agriculture: Forest Service, Methods for Calculating Forest Ecosystem and harvest Carbon with Standard Estimates for Forest Types of the United States, 2006, available at http://www.treesearch.fs.fed.us/pubs/22954. We also utilized United States Department of Agriculture: Forest Service, Carbon Storage and Accumulation in United States Forest Ecosystems, 1992, available at http://www.nrs.fs.fed.us/pubs/gtr/gtr_wo059.pdf.