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  • Glossary item | Last updated: 21 Mar 2024

CO2 equivalent

A metric measure used to compare the emissions from various greenhouse gases on the basis of their global-warming potential (GWP), by converting amounts of other gases to the equivalent amount of carbon dioxide with the same global warming potential. Carbon dioxide equivalents are commonly expressed as million metric tonnes of carbon dioxide equivalents, abbreviated as MMTCDE.

The carbon dioxide equivalent for a gas is derived by multiplying the tonnes of the gas by the associated GWP:

MMTCDE = (million metric tonnes of a gas) * (GWP of the gas).

For example, the GWP for methane is 25 and for nitrous oxide 298. This means that emissions of 1 million metric tonnes of methane and nitrous oxide respectively is equivalent to emissions of 25 and 298 million metric tonnes of carbon dioxide.

Eurostat b, Glossary, accessed 05 December 2023

Source category: EC Technical Documents