CO2e (Carbon dioxide equivalent)

The universal unit of measurement used to indicate the global warming potential (GWP) of each greenhouse gas . Carbon dioxide (CO2) is a naturally occurring gas that is a byproduct of burning fossil fuels and biomass, land-use changes, and other industrial processes. CO2 is used as the reference gas against which the other greenhouse gases are measured since it has the smallest GWP. CO2 emissions are reported in CO2e; the standard unit is MtCO2e or metric tons or tons of carbon dioxide equivalent. The global warming impact of all greenhouse gases is measured in terms of equivalency to the impact of carbon dioxide (CO2) via global warming potentials. For example, one million tons of emitted methane, a far more potent greenhouse gas than carbon dioxide, is measured as 23 million metric tons of CO2 equivalent, or 23 million MtCO2e.