Greenhouse Gas Emissions from Transportation
Mobiles sources like road, rail, air and water transportation produce direct greenhouse gas emissions of carbon dioxide, methane and nitrous oxide from the combustion of various fuels (mostly diesel and gasoline).
In this calculator, the method used for estimating transportation emissions is called the Tier 1 methodology, the simplest method and with the fewest data requirements. In Tier 1 methodology, the general equation used is:
GHG Emissions per GHG = Activity data x Emission Factor per GHG
Activity data used in this calculator is the distance travelled by the vehicle (in kilometers). This comes from the input of the user of the calculator. On the other hand, emission factors for transportation emissions were derived from this National Center for Transportation Studies (NCTS) paper.