Similarly, a study last year by the National Institute of Livestock and Grassland Science in Japan estimated that 2.2 pounds of beef is responsible for the equivalent amount of carbon dioxide emitted by the average European car every 155 miles, and burns enough energy to light a 100-watt bulb for nearly 20 days" (Bittman 2008)
The fact that I do not rely on private automobile transportation or make extensive use of gasoline-powered public transportation is probably the principal reason that my carbon footprint is so much lower than the national average. In principle, "carbon footprint" is the measure of the amount of carbon dioxide emitted from the combustion of fossil fuels (Crittenden & White, 2010)
Likewise, because I am often pressed for time, I do rely on convenience items such as bottled water and other goods and services that add to the national ecological footprint more than necessary. The byproducts of producing, transporting, and managing the waste disposal of the bottles and other packaging used in that regard on a large scale contribute tremendously to the societal ecological footprint (Matthews, Hendrickson, & Weber, 2008)