A carbon footprint is defined as: The total amount of greenhouse gases produced to directly and indirectly support human activities, usually expressed in equivalent tons of carbon dioxide (CO2). Form an organization point of view it is defined as: It is a calculation of the total greenhouse gas emissions caused directly and indirectly by an organization or company. This is typically calculated and reported over a period of 12 months. In short a carbon footprint measures the total greenhouse gas emissions caused directly and indirectly by a person, organization, event or product. The carbon dioxide equivalent (CO2e) allows the different greenhouse gases to be compared on a like-for-like basis relative to one unit of CO2. CO2e is calculated by multiplying the emissions of each of the six greenhouse gases by its 100 year global warming potential (GWP). In calculation of carbon footprint all six of the Kyoto Protocol greenhouse gases are considered i.e. Carbon dioxide (CO2), Methane (CH4), Nitrous oxide (N2O), Hydrofluorocarbons (HFCs), Perfluorocarbons (PFCs) and Sulphur hexafluoride (SF6).
