The amount of carbon dioxide by weight emitted into the atmosphere that would produce the same estimated radiative forcing as a given weight of another radiatively active gas. Carbon dioxide equivalents are computed by multiplying the weight of the gas being measured (for example, methane) by its estimated global warming potential (which is 21 for methane). "Carbon equivalent units" are defined as carbon dioxide equivalents multiplied by the carbon content of carbon dioxide (i.e., 12/44).
Different greenhouse gases have different levels of impact on global warming. Emissions of greenhouse gases are often measured in CO2 equivalents. A tonne of each individual greenhouse gas is adjusted to be expressed in terms of how many tonnes of CO2 would be needed to produce the same global warming impact over 100 years.
A measure used to compare different greenhouse gases based on their contribution to climate change. The UNFCCC currently (2005) uses global warming potentials (GWPs). The GWPs are calculated as the ratio of the radiative forcing of one kilogram of greenhouse gas emitted to the atmosphere to that of one kilogram of CO2 over a period of time (100 years).
an atmospheric carbon dioxide concentration that would have the same radiative forcing effect as all of the human-produced greenhouse gases combined
Measure used to compare the emissions of various greenhouse gases based on their global warming potential. Expressed in carbon dioxide (CO2), a primary greenhouse gas.
A metric measure used to compare the emissions of the different GHGs based upon their global warming potential. Global warming potentials are used to convert GHGs to CO2e.
The universal unit of measurement used to indicate the global warming potential (GWP) of each of the 6 greenhouse gases. It is used to evaluate the impacts of releasing (or avoiding the release of) different greenhouse gases.
A metric measure used to compare the emissions from various greenhouse gases based upon their global warming potential (GWP). Carbon dioxide equivalents are commonly expressed as "million metric tons of carbon dioxide equivalents (MMTCDE)" or "million short tons of carbon dioxide equivalents (MSTCDE)" The carbon dioxide equivalent for a gas is derived by multiplying the tons of the gas by the associated GWP. MMTCDE= (million metric tons of a gas) * (GWP of the gas) For example, the GWP for methane is 24.5. This means that emissions of one million metric tons of methane is equivalent to emissions of 24.5 million metric tons of carbon dioxide. Carbon may also be used as the reference and other greenhouse gases may be converted to carbon equivalents. To convert carbon to carbon dioxide, multiply the carbon by 44/12 (the ratio of the molecular weight of carbon dioxide to carbon). (EPA)
is a unit of measure used to allow the addition of or the comparison between gases that have different global warming potentials (GWPs). Since many greenhouse gases (GHGs) exist and their GWPs vary, the emissions are added in a common unit, CO2 eq. To express GHG emissions in units of CO2 eq., the quantity of a given GHG (expressed in units of mass) is multiplied by its GWP.
A metric measure used to compare the emissions from various greenhouse gases based upon their global warming potential (GWP). The carbon dioxide equivalent for a gas is derived by multiplying the mass of the gas by the associated GWP. CDE = (mass of a gas) * (GWP of the gas) Note generally the unit used is Gg ( 109 g = 1 000 tons ) or Tg ( 1012 g = 1 million tons )
The concentration of carbon dioxide that would cause the same amount of radiative forcing as a given mixture of carbon dioxide and other greenhouse gases. Carbon dioxide equivalents are generally computed by multiplying the amount (in kilograms) of the gas of interest (for example, methane) by its estimated global warming potential. Some analysts (and this report) use "carbon equivalent units" for convenience, defined as carbon dioxide equivalents multiplied by the carbon content of carbon dioxide (i.e., 12/44).
A metric measure used to compare the emissions from various greenhouse gases based upon their global warming potential (GWP). Carbon dioxide equivalents are commonly expressed as 'million metric tonnes of carbon dioxide equivalents (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 21 and for nitrous oxide 310. This means that emissions of 1million metric tonnes of methane and nitrous oxide respectively is equivalent to emissions of 21 and 310 million metric tonnes of carbon dioxide.
The emissions of a gas, by weight, multiplied by its "global warming potential."
Carbon dioxide equivalent or CO2e, is an internationally accepted measure that encapsulates all GHGs (greenhouse gases) that contribute to global warming (e.g. methane, perfluorocarbons, nitrous oxide, etc). The CO2e of an amount of a greenhouse gas is the amount of carbon dioxide that would have the same global warming potential (GWP), measured over a specified timescale (e.g. 100 years) for emissions or current GWP for existing GHG concentrations.