… refers to the economic benefits generated by production activities that produce carbon emissions at the same time. The less carbon emissions generated per unit of economic output, the more carbon emission efficient it is.

Scholarly Encyclopedia

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…shorthand for emissions of seven greenhouse gases (GHGs) covered by the Kyoto Protocol:

  • carbon dioxide (CO2),
  • methane (CH4),
  • nitrous oxide (N2O),
  • hydrofluorocarbons (HFCs),
  • perfluorocarbons (PFCs),
  • sulfur hexafluoride (SF6), and
  • nitrogen trifluoride (NF3).

It is common practice to express GHGs as a single unit, CO2-equivalents (CO2e), signifying the amount of CO2 that would have the equivalent impact on global warming.

Ecological Economics Vol 175, Sept 2020

Also known as Carbon Footprint

carbon footprint: “Measure of the exclusive total amount of emissions of carbon dioxide (CO2 ) that is directly and indirectly caused by an activity or is accumulated over the lifecycle stages of a product.