According to Carbon Footprint, there are indirect and direct elements that make up our carbon footprint. The direct carbon footprint is the individual quantity of CO2 emissions originated from the burning of fossil fuels, through domestic energy consumption and transportation. As the term suggests, this is based on the direct consumption of each person. The indirect carbon footprint, on the other hand, is the CO2 emissions generated from all products we use, from food to books. Such emissions are linked to the manufacturing, disposal and recycling potential of the products.
Fossil fuels are the main culprits in generating carbon emissions, and they include gasoline, diesel, oil, gas and coal. According to Time For Change, each gallon of gasoline consumed liberates 8.7 kg carbon dioxide (CO2) in the atmosphere. If you use diesel, you are likely to have a bigger carbon footprint, as 9.95 kg are emitted to each gallon burned.
The term "carbon footprint" originated from the expression "ecologic footprint," which relates to the human consumption of natural resources. The expression "ecologic footprint" was first used in 1990 by Mathis Wackernagel and William Rees during a Ph.D. study at the University of British Columbia, according to Global Footprint Network.
According to ISA Research & Consulting, an academic definition of carbon footprint must include direct and indirect CO2 emissions, exclude noncarbonic compounds and be expressed in a mass measurement unit (g or kg). In a document published in 2007, ISA Research & Consulting scientifically defined carbon footprint as "a measure of the exclusive total amount of carbon dioxide emissions that is directly and indirectly caused by an activity or is accumulated over the life stages of a product."
To ISA Research & Consulting, businesses, NGOs and government have defined "carbon footprint" due to the lack of a scientific concept. This created some misconceptions, such as the use of the term to define the emission of greenhouse gases like methane and nitrous oxide, also generated when burning fossil fuels.
