Such units can be for example tonnes CO2-eq per year, per kilogram of protein for consumption, per kilometer travelled, per piece of clothing and so forth.
So the carbon footprint concept allows everyone to make comparisons between the climate impacts of individuals, products, companies and countries.
This comprehensive carbon footprint reporting including Scope 3 emissions deals with gaps in current systems.
[7] Comprehensive carbon footprint reporting looks at the final demand for emissions, to where the consumption of the goods and services takes place.
[8] A formal definition of carbon footprint is as follows: "A measure of the total amount of carbon dioxide (CO2) and methane (CH4) emissions of 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.
Emissions caused indirectly by an organization, such as by purchasing secondary energy sources like electricity, heat, cooling or steam are called Scope 2.
[30] The Paris Agreement aims to reduce greenhouse gas emissions enough to limit the rise in global temperature to no more than 1.5°C above pre-industrial levels.
[31][32] The carbon footprint concept makes comparisons between the climate impacts of individuals, products, companies and countries.
For meat products, as an example, such a label could make it clear that beef has a higher carbon footprint than chicken.
[35] Large companies in sectors such as clothing or automobiles would need to examine more than 100,000 supply chain pathways to fully report their carbon footprints.
These include increased air pollution,[41] water scarcity,[42] biodiversity loss,[43] raw material usage,[44] and energy depletion.
[6][5] Including consumption-based calculations in the UNFCCC reporting requirements would help close loopholes by addressing the challenge of carbon leakage.
[41] The Paris Agreement currently does not require countries to include in their national totals GHG emissions associated with international transport.
The calculation of the carbon footprint of a product, service or sector requires expert knowledge and careful examination of what is to be included.
[53] Consumption-based emission accounting traces the impacts of demand for goods and services along the global supply chain to the end-consumer.
[65][66] The fossil fuel company BP ran a large advertising campaign for the personal carbon footprint in 2005 which helped popularize this concept.
[65] This strategy, employed by many major fossil fuel companies, has been criticized for trying to shift the blame for negative consequences of those industries on to individual choices.
[65][67] Geoffrey Supran and Naomi Oreskes of Harvard University argue that concepts such as carbon footprints "hamstring us, and they put blinders on us, to the systemic nature of the climate crisis and the importance of taking collective action to address the problem".
[68][69] A focus on carbon footprints can lead people to ignore or even exacerbate other related environmental issues of concern.
[70]: 223 The carbon footprint analysis solely focuses on greenhouse gas emissions, unlike a life-cycle assessment which is much broader and looks at all environmental impacts.
[57]: 280 It is based on input-output tables of countries' national accounts and international trade data such as UN Comtrade,[75] and therefore it is comparable worldwide.
[74] The term carbon footprint has been applied to limited calculations that do not include Scope 3 emissions or the entire supply chain.
Carbon dioxide (CO2), from burning fossil fuels such as coal, oil, and natural gas, is the main cause of climate change.
This means the choice of what to eat has a larger potential to reduce carbon footprint than how far the food has traveled, or how much packaging it is wrapped in.
[5] According to the World Bank, the global average carbon footprint in 2014 was about 5 tonnes of CO2 per person, measured on a production basis.
[91] Assuming a global population of around 9–10 billion by 2050, a carbon footprint of about 2–2.5 tonnes CO2e per capita is needed to stay within a 2 °C target.
This database accounts for all greenhouse gas (GHG) emissions in the global supply chain and allocates them to the final consumer of the purchased commodities.
Efforts to reduce the carbon footprint of products, services and organizations help limit climate change.
[102] In 2005, fossil fuel company BP hired the large advertising campaign Ogilvy to popularize the idea of a carbon footprint for individuals.
[108] The International Sustainability Standards Board (ISSB) aims to bring global, rigorous oversight to carbon footprint reporting.