Carbon footprint (CF) is the amount of carbon (usually in tonnes) being emitted by an activity or organization. It (CF) is a measure of the total amount of greenhouse gases (GHGs) such as CO2 and CH4 being emitted from a defined population, system or activity, considering all relevant sources, sinks and storage within the spatial and temporal boundary of the population, system or activity of interest. CF is calculated as carbon dioxide equivalent (CO2e) using the relevant 100-year global warming potential (GWP100).
An individual’s CF is the amount of GHGs s/he is responsible for including electricity use at home (electric appliances, hot water and cold water use- all of these activities require energy), food s/he eat (need fertiliser to grow and energy to harvest, process, transport), clothes s/he wear (need energy to make), house that s/he live (is the house environmentally friendly or low carbon home) and, use of car (require burning of fossil fuels) etc.
We can reduce GHGs emissions (mitigation) by using (a) alternate energy sources (renewable energy such as solar, wind); (b) reducing, re-using and recycling the resources; (c) maintaining green lifestyle (walking or biking or using public transport instead of using personal car); (d) planting tress (reforestation/afforestation); (e) eating less red meat since cattle and sheep causes significant GHGs emissions); (f) use of tap water instead of bottled water (greenhouse gas produced for each bottle of water is significantly higher); (g) eating fresh food instead of processed food (processed food needs more energy to produce it, package it and ship it than fresh food), (h) insulating the house etc.
Theoretically the carbon footprint would indicate the ability of a country or region to live sustainably ad infinitum.
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However the carbon footprint (or ecological footprint) is an index that alone says nothing, or worse is an index that while others celebrate because Haitians, Pakistanis or has a carbon footprint much smaller than the Americans and Danes. However Haitians and Pakistanis may wish to have a high carbon footprint.
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I consider that the mere quantification of carbon footprint as sustainability index is a real nonsense, because it is an index that is strongly correlated with the GDR per capita than anything else. (countries with higher Carbon footprint: United Arab Emirates, Qatar, Denmark, United States of America, Belgium, Estonia, Canada, Australia, Kuwait - countries with lower Carbon footprint: Bangladesh, Afghanistan, Haiti, Malawi, Democratic Republic of Congo, Pakistan , Mozambique, Eritrea, Burundi 2010 data), and how countries with lower carbon present current conditions of high infant mortality rate, diseases and poor quality of life, they now live under conditions of sustainability!
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Calculating the Carbon footprint is coordinated by a team of researchers from countries belonging to the OECD (http://www.footprintnetwork.org/en/index.php/GFN/page/our_team/) and the calculation method are established by groups of same origin through standards and methodologies established by the same (http://www.footprintnetwork.org/images/uploads/Ecological_Footprint_Standards_2009.pdf and http://www.footprintnetwork.org/images/uploads/National_Footprint_Accounts_Method_Paper_2010.pdf).
maybe marginal to your question, but potentially relevant for the basics:
I would suggest that a carbon footprint, foremost, is a concept for a particular form of political calculation. Carbon footprints are usually referred to in relation to a politics of managing or governing climate change. And they usually are referred to as if they can be calculated (in principle).
A large range of methodologies for conducting such calculations exist. Calculations are performed across all kinds of scales, eg for "all humans/earth", for a region, a country, for an industry sector, for a company, for a household, for individual people, for pets...
I published some texts that addresses how a company actually calculated its carbon footprint. "Actually" implies that I attended to both the formal methodologies as well all the informal aspects of achieving such a calculation. In short, my PhD was an ethnography of carbon accountants, i.e. workers, who conducted the calculations to produce something that counted for the purposes of their company as a carbon footprint, i.e.. form of fact.
Kind regards,
Ingmar
dx.doi.org/10/6vh
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