Global warming potential - Revision history

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← Previous revision		Revision as of 03:31, 21 December 2025
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	{{Short description\|Potential heat absorbed by a greenhouse gas}}		{{Short description\|Potential heat absorbed by a greenhouse gas}}
	[[File:Perfluorotributylamine-global-warming-potential.jpg\|thumb\|Comparison of global warming potential ~~(GWP)~~ of three [[greenhouse gas]]es over a 100-year period: [[Perfluorotributylamine]], [[nitrous oxide]] and [[methane]], compared to [[carbon dioxide]] (the latter is the reference value, therefore it has a GWP of one)]]		[[File:Perfluorotributylamine-global-warming-potential.jpg\|thumb\|Comparison of global warming potential of three [[greenhouse gas]]es over a 100-year period (GWP-100): [[Perfluorotributylamine]], [[nitrous oxide]] and [[methane]], compared to [[carbon dioxide]] (the latter is the reference value, therefore it has a GWP of one)]]

	'''Global warming potential''' ('''GWP''') is a measure of how much heat a [[greenhouse gas]] traps in the atmosphere over a specific time period, relative to [[carbon dioxide]] ({{CO2}}).<ref name=":2" />{{Rp\|page=2232}} It is expressed as a multiple of warming caused by the same [[mass]] of ({{CO2}}). Therefore, by definition {{CO2}} has a GWP of 1. For other [[gas]]es it depends on how strongly the gas absorbs thermal radiation, how quickly the gas leaves the atmosphere, and the time frame considered.		'''Global warming potential''' ('''GWP''') is a measure of how much heat a [[greenhouse gas]] traps in the atmosphere over a specific time period, relative to [[carbon dioxide]] ({{CO2}}).<ref name=":2" />{{Rp\|page=2232}} It is expressed as a multiple of warming caused by the same [[mass]] of ({{CO2}}). Therefore, by definition {{CO2}} has a GWP of 1. For other [[gas]]es it depends on how strongly the gas absorbs thermal radiation, how quickly the gas leaves the atmosphere, and the time frame considered.

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2601:243:1702:40:F806:8C96:6899:8A9B: Adding commas to numbers.

2025-06-29T18:48:13Z

Adding commas to numbers.

← Previous revision		Revision as of 18:48, 29 June 2025
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	\|52		\|52
	\|{{val\|0.29}}		\|{{val\|0.29}}
	\|~~8321~~		\|8,321
	\|~~6226~~		\|6,226
	\|~~2093~~		\|2,093
	\|-		\|-
	\| style="text-align:left;" \|[[CFC-12]] (R-12)		\| style="text-align:left;" \|[[CFC-12]] (R-12)
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	\|100		\|100
	\|{{val\|0.32}}		\|{{val\|0.32}}
	\|~~10800~~		\|10,800
	\|~~10200~~		\|10,200
	\|~~5200~~		\|5,200
	\|-		\|-
	\| style="text-align:left;" \|[[HCFC-22]] (R-22)		\| style="text-align:left;" \|[[HCFC-22]] (R-22)
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	\|12		\|12
	\|{{val\|0.21}}		\|{{val\|0.21}}
	\|~~5280~~		\|5,280
	\|~~1760~~		\|1,760
	\|549		\|549
	\|-		\|-
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	\|5		\|5
	\|{{val\|0.11}}		\|{{val\|0.11}}
	\|~~2693~~		\|2,693
	\|771		\|771
	\|220		\|220
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	\|14		\|14
	\|{{val\|0.17}}		\|{{val\|0.17}}
	\|~~4144~~		\|4,144
	\|~~1526~~		\|1,526
	\|436		\|436
	\|-		\|-
	\| style="text-align:left;" \|[[Tetrafluoromethane]] (R-14)		\| style="text-align:left;" \|[[Tetrafluoromethane]] (R-14)
	\| style="text-align:center;" \|{{chem\|CF\|4}}		\| style="text-align:center;" \|{{chem\|CF\|4}}
	\|~~50000~~		\|50,000
	\|{{val\|0.09}}		\|{{val\|0.09}}
	\|~~5301~~		\|5,301
	\|~~7380~~		\|7,380
	\|~~10587~~		\|10,587
	\|-		\|-
	\| style="text-align:left;" \|[[Hexafluoroethane]]		\| style="text-align:left;" \|[[Hexafluoroethane]]
	\| style="text-align:center;" \|{{chem\|C\|2\|F\|6}}		\| style="text-align:center;" \|{{chem\|C\|2\|F\|6}}
	\|~~10000~~		\|10,000
	\|{{val\|0.25}}		\|{{val\|0.25}}
	\|~~8210~~		\|8,210
	\|~~11100~~		\|11,100
	\|~~18200~~		\|18,200
	\|-		\|-
	\| style="text-align:left;" \|[[Sulfur hexafluoride]]		\| style="text-align:left;" \|[[Sulfur hexafluoride]]
	\| style="text-align:center;" \|{{chem\|SF\|6}}		\| style="text-align:center;" \|{{chem\|SF\|6}}
	\|~~3200~~		\|3,200
	\|{{val\|0.57}}		\|{{val\|0.57}}
	\|~~17500~~		\|17,500
	\|~~23500~~		\|23,500
	\|~~32600~~		\|32,600
	\|-		\|-
	\| style="text-align:left;" \|[[Nitrogen trifluoride]]		\| style="text-align:left;" \|[[Nitrogen trifluoride]]
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	\|500		\|500
	\|{{val\|0.20}}		\|{{val\|0.20}}
	\|~~12800~~		\|12,800
	\|~~16100~~		\|16,100
	\|~~20700~~		\|20,700
	\|-		\|-
	! colspan="7" \|<small><sup>(A)</sup> No single lifetime for atmospheric {{CO2}} can be given.</small>		! colspan="7" \|<small><sup>(A)</sup> No single lifetime for atmospheric {{CO2}} can be given.</small>
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	\|[[HFC-134a]] ([[hydrofluorocarbon]])		\|[[HFC-134a]] ([[hydrofluorocarbon]])
	\|14.0<ref name="ar6 WG1 Ch 7" />		\|14.0<ref name="ar6 WG1 Ch 7" />
	\| data-sort-value="~~4000~~" \|3,710 / 3,790f<ref name="ar5" /><br />4,144<ref name="ar6 WG1 Ch 7" />		\| data-sort-value="4,000" \|3,710 / 3,790f<ref name="ar5" /><br />4,144<ref name="ar6 WG1 Ch 7" />
	\| data-sort-value="~~1500~~" \|1,300 / 1,550f<ref name="ar5" /><br />1,526<ref name="ar6 WG1 Ch 7" />		\| data-sort-value="1,500" \|1,300 / 1,550f<ref name="ar5" /><br />1,526<ref name="ar6 WG1 Ch 7" />
	\| data-sort-value="435" \|435<ref name="ar4" /><br />436<ref name="ar6 WG1 Ch 7" />		\| data-sort-value="435" \|435<ref name="ar4" /><br />436<ref name="ar6 WG1 Ch 7" />
	\|-		\|-
	\|[[CFC-11]] ([[chlorofluorocarbon]])		\|[[CFC-11]] ([[chlorofluorocarbon]])
	\|52.0<ref name="ar6 WG1 Ch 7" />		\|52.0<ref name="ar6 WG1 Ch 7" />
	\| data-sort-value="~~7000~~" \|6,900 / 7,020f<ref name="ar5" /><br />8,321<ref name="ar6 WG1 Ch 7" />		\| data-sort-value="7,000" \|6,900 / 7,020f<ref name="ar5" /><br />8,321<ref name="ar6 WG1 Ch 7" />
	\| data-sort-value="~~5000~~" \|4,660 / 5,350f<ref name="ar5" /><br />6,226<ref name="ar6 WG1 Ch 7" />		\| data-sort-value="5,000" \|4,660 / 5,350f<ref name="ar5" /><br />6,226<ref name="ar6 WG1 Ch 7" />
	\| data-sort-value="~~2000~~" \|1,620<ref name="ar4" /><br />2,093<ref name="ar6 WG1 Ch 7" />		\| data-sort-value="2,000" \|1,620<ref name="ar4" /><br />2,093<ref name="ar6 WG1 Ch 7" />
	\|-		\|-
	\|[[Carbon tetrafluoride]] (CF{{sub\|4}} / PFC-14)		\|[[Carbon tetrafluoride]] (CF{{sub\|4}} / PFC-14)
	\|50,000<ref name="ar6 WG1 Ch 7" />		\|50,000<ref name="ar6 WG1 Ch 7" />
	\| data-sort-value="~~5000~~" \|4,880 / 4,950f<ref name="ar5" /><br />5,301<ref name="ar6 WG1 Ch 7" />		\| data-sort-value="5,000" \|4,880 / 4,950f<ref name="ar5" /><br />5,301<ref name="ar6 WG1 Ch 7" />
	\| data-sort-value="~~7000~~" \|6,630 / 7,350f<ref name="ar5" /><br />7,380<ref name="ar6 WG1 Ch 7" />		\| data-sort-value="7,000" \|6,630 / 7,350f<ref name="ar5" /><br />7,380<ref name="ar6 WG1 Ch 7" />
	\| data-sort-value="~~11000~~" \|11,200<ref name="ar4" /><br />10,587<ref name="ar6 WG1 Ch 7" />		\| data-sort-value="11,000" \|11,200<ref name="ar4" /><br />10,587<ref name="ar6 WG1 Ch 7" />
	\|-		\|-
	\| [[HFC-23]] ([[hydrofluorocarbon]])		\| [[HFC-23]] ([[hydrofluorocarbon]])
	\|222<ref name="ar5" />		\|222<ref name="ar5" />
	\| data-sort-value="~~11000~~" \|12,000<ref name="ar4" /><br />10,800<ref name="ar5" />		\| data-sort-value="11,000" \|12,000<ref name="ar4" /><br />10,800<ref name="ar5" />
	\| data-sort-value="~~13000~~" \|14,800<ref name="ar4" /><br />12,400<ref name="ar5" />		\| data-sort-value="13,000" \|14,800<ref name="ar4" /><br />12,400<ref name="ar5" />
	\| data-sort-value="~~12200~~" \|12,200<ref name="ar4" />		\| data-sort-value="12,200" \|12,200<ref name="ar4" />
	\|-		\|-
	\|[[Sulfur hexafluoride]] {{chem2\|SF6}}		\|[[Sulfur hexafluoride]] {{chem2\|SF6}}
	\|3,200<ref name="ar5" />		\|3,200<ref name="ar5" />
	\| data-sort-value="~~17000~~" \|16,300<ref name="ar4" /><br />17,500<ref name="ar5" />		\| data-sort-value="17,000" \|16,300<ref name="ar4" /><br />17,500<ref name="ar5" />
	\| data-sort-value="~~23000~~" \|22,800<ref name="ar4" /><br />23,500<ref name="ar5" />		\| data-sort-value="23,000" \|22,800<ref name="ar4" /><br />23,500<ref name="ar5" />
	\| data-sort-value="~~32600~~" \|32,600<ref name="ar4" />		\| data-sort-value="32,600" \|32,600<ref name="ar4" />
	\|}		\|}

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← Previous revision		Revision as of 03:31, 21 December 2025
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	{{Short description\|Potential heat absorbed by a greenhouse gas}}		{{Short description\|Potential heat absorbed by a greenhouse gas}}
	[[File:Perfluorotributylamine-global-warming-potential.jpg\|thumb\|Comparison of global warming potential ~~(GWP)~~ of three [[greenhouse gas]]es over a 100-year period: [[Perfluorotributylamine]], [[nitrous oxide]] and [[methane]], compared to [[carbon dioxide]] (the latter is the reference value, therefore it has a GWP of one)]]		[[File:Perfluorotributylamine-global-warming-potential.jpg\|thumb\|Comparison of global warming potential of three [[greenhouse gas]]es over a 100-year period (GWP-100): [[Perfluorotributylamine]], [[nitrous oxide]] and [[methane]], compared to [[carbon dioxide]] (the latter is the reference value, therefore it has a GWP of one)]]

	'''Global warming potential''' ('''GWP''') is a measure of how much heat a [[greenhouse gas]] traps in the atmosphere over a specific time period, relative to [[carbon dioxide]] ({{CO2}}).<ref name=":2" />{{Rp\|page=2232}} It is expressed as a multiple of warming caused by the same [[mass]] of ({{CO2}}). Therefore, by definition {{CO2}} has a GWP of 1. For other [[gas]]es it depends on how strongly the gas absorbs thermal radiation, how quickly the gas leaves the atmosphere, and the time frame considered.		'''Global warming potential''' ('''GWP''') is a measure of how much heat a [[greenhouse gas]] traps in the atmosphere over a specific time period, relative to [[carbon dioxide]] ({{CO2}}).<ref name=":2" />{{Rp\|page=2232}} It is expressed as a multiple of warming caused by the same [[mass]] of ({{CO2}}). Therefore, by definition {{CO2}} has a GWP of 1. For other [[gas]]es it depends on how strongly the gas absorbs thermal radiation, how quickly the gas leaves the atmosphere, and the time frame considered.

← Previous revision		Revision as of 15:19, 30 October 2025
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	[[File:Perfluorotributylamine-global-warming-potential.jpg\|thumb\|Comparison of global warming potential (GWP) of three [[greenhouse gas]]es over a 100-year period: [[Perfluorotributylamine]], [[nitrous oxide]] and [[methane]], compared to [[carbon dioxide]] (the latter is the reference value, therefore it has a GWP of one)]]		[[File:Perfluorotributylamine-global-warming-potential.jpg\|thumb\|Comparison of global warming potential (GWP) of three [[greenhouse gas]]es over a 100-year period: [[Perfluorotributylamine]], [[nitrous oxide]] and [[methane]], compared to [[carbon dioxide]] (the latter is the reference value, therefore it has a GWP of one)]]

	'''Global warming potential (GWP)''' is a measure of how much heat a [[greenhouse gas]] traps in the atmosphere over a specific time period, relative to [[carbon dioxide]] ({{CO2}}).<ref name=":2" />{{Rp\|page=2232}} It is expressed as a multiple of warming caused by the same [[mass]] of ~~[[carbon dioxide]]~~ ({{CO2}}). Therefore, by definition {{CO2}} has a GWP of 1. For other [[gas]]es it depends on how strongly the gas absorbs thermal radiation, how quickly the gas leaves the atmosphere, and the time frame considered.		'''Global warming potential''' ('''GWP''') is a measure of how much heat a [[greenhouse gas]] traps in the atmosphere over a specific time period, relative to [[carbon dioxide]] ({{CO2}}).<ref name=":2" />{{Rp\|page=2232}} It is expressed as a multiple of warming caused by the same [[mass]] of ({{CO2}}). Therefore, by definition {{CO2}} has a GWP of 1. For other [[gas]]es it depends on how strongly the gas absorbs thermal radiation, how quickly the gas leaves the atmosphere, and the time frame considered.

	For example, [[Methane emissions\|methane]] has a GWP over 20 years (GWP-20) of 81.2<ref name=":0">{{Citation \|title=7.SM.6 Tables of greenhouse gas lifetimes, radiative efficiencies and metrics \|date=2021 \|url=https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter_07_Supplementary_Material.pdf \|page=7SM-24 \|publisher=[[IPCC]]}}.</ref> meaning that, a [[Fugitive gas emissions\|leak]] of a tonne of methane is equivalent to emitting 81.2 tonnes of carbon dioxide measured over 20 years. As methane has a much shorter atmospheric lifetime than carbon dioxide, its GWP is much less over longer time periods, with a GWP-100 of 27.9 and a GWP-500 of 7.95.<ref name=":0" />{{Rp\|page=7SM-24}}		For example, [[Methane emissions\|methane]] has a GWP over 20 years (GWP-20) of 81.2<ref name=":0">{{Citation \|title=7.SM.6 Tables of greenhouse gas lifetimes, radiative efficiencies and metrics \|date=2021 \|url=https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter_07_Supplementary_Material.pdf \|page=7SM-24 \|publisher=[[IPCC]]}}.</ref> meaning that, a [[Fugitive gas emissions\|leak]] of a tonne of methane is equivalent to emitting 81.2 tonnes of carbon dioxide measured over 20 years. As methane has a much shorter atmospheric lifetime than carbon dioxide, its GWP is much less over longer time periods, with a GWP-100 of 27.9 and a GWP-500 of 7.95.<ref name=":0" />{{Rp\|page=7SM-24}}
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	== Calculation methods ==		== Calculation methods ==
	[[File:1979-_Radiative_forcing_-_climate_change_-_global_warming_-_EPA_NOAA.svg\|right\|thumb\|upright=1.6\|The [[radiative forcing]] (warming influence) of long-lived atmospheric greenhouse gases has accelerated, almost doubling in 40 years.<ref name=NOAA_AGGI_2023>{{cite web \|title=The NOAA Annual Greenhouse Gas Index (AGGI) \|url=https://gml.noaa.gov/aggi/aggi.html \|website=NOAA.gov \|publisher=National Oceanic and Atmospheric Administration (NOAA) \|archive-url=https://web.archive.org/web/20241005195609/https://gml.noaa.gov/aggi/aggi.html \|archive-date=5 October 2024 \|date=2024 \|url-status=live }}</ref><ref>{{Cite web \|title=Annual Greenhouse Gas Index \|url=https://www.globalchange.gov/browse/indicators/annual-greenhouse-gas-index \|url-status=~~live~~ \|archive-url=https://web.archive.org/web/20210421143115/https://www.globalchange.gov/browse/indicators/annual-greenhouse-gas-index \|archive-date=21 April 2021 \|access-date=5 September 2020 \|publisher=U.S. Global Change Research Program}}</ref><ref name="butmon">{{Cite web \|author=Butler J. and Montzka S. \|year=2020 \|title=The NOAA Annual Greenhouse Gas Index (AGGI) \|url=https://www.esrl.noaa.gov/gmd/aggi/aggi.html \|url-status=live \|archive-url=https://web.archive.org/web/20130922035917/https://www.esrl.noaa.gov/gmd/aggi/aggi.html \|archive-date=22 September 2013 \|access-date=5 September 2020 \|publisher=[[NOAA]] Global Monitoring Laboratory/Earth System Research Laboratories}}</ref>]]		[[File:1979-_Radiative_forcing_-_climate_change_-_global_warming_-_EPA_NOAA.svg\|right\|thumb\|upright=1.6\|The [[radiative forcing]] (warming influence) of long-lived atmospheric greenhouse gases has accelerated, almost doubling in 40 years.<ref name=NOAA_AGGI_2023>{{cite web \|title=The NOAA Annual Greenhouse Gas Index (AGGI) \|url=https://gml.noaa.gov/aggi/aggi.html \|website=NOAA.gov \|publisher=National Oceanic and Atmospheric Administration (NOAA) \|archive-url=https://web.archive.org/web/20241005195609/https://gml.noaa.gov/aggi/aggi.html \|archive-date=5 October 2024 \|date=2024 \|url-status=live }}</ref><ref>{{Cite web \|title=Annual Greenhouse Gas Index \|url=https://www.globalchange.gov/browse/indicators/annual-greenhouse-gas-index \|url-status=dead \|archive-url=https://web.archive.org/web/20210421143115/https://www.globalchange.gov/browse/indicators/annual-greenhouse-gas-index \|archive-date=21 April 2021 \|access-date=5 September 2020 \|publisher=U.S. Global Change Research Program}}</ref><ref name="butmon">{{Cite web \|author=Butler J. and Montzka S. \|year=2020 \|title=The NOAA Annual Greenhouse Gas Index (AGGI) \|url=https://www.esrl.noaa.gov/gmd/aggi/aggi.html \|url-status=live \|archive-url=https://web.archive.org/web/20130922035917/https://www.esrl.noaa.gov/gmd/aggi/aggi.html \|archive-date=22 September 2013 \|access-date=5 September 2020 \|publisher=[[NOAA]] Global Monitoring Laboratory/Earth System Research Laboratories}}</ref>]]
	When calculating the GWP of a greenhouse gas, the value depends on the following factors:		When calculating the GWP of a greenhouse gas, the value depends on the following factors:
	* the absorption of [[infrared radiation]] by the given gas		* the absorption of [[infrared radiation]] by the given gas
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	=== Carbon dioxide equivalent ===		=== Carbon dioxide equivalent ===
	Carbon dioxide equivalent ({{CO2}}e or {{CO2}}eq or {{CO2}}-e) of a quantity of gas is calculated from its GWP. For any gas, it is the mass of {{CO2}} which would warm the earth as much as the mass of that gas.<ref name="epadef">{{Cite web\|title=CO2e\|url=https://www3.epa.gov/carbon-footprint-calculator/tool/definitions/co2e.html\|access-date=2020-06-27\|website=www3.epa.gov}}</ref> Thus it provides a common scale for measuring the climate effects of different gases. It is calculated as GWP multiplied by mass of the other gas. For example, if a gas has GWP of 100, two tonnes of the gas have {{CO2}}e of 200 tonnes, and 9 tonnes of the gas has {{CO2}}e of 900 tonnes.		Carbon dioxide equivalent ({{CO2}}e or {{CO2}}eq or {{CO2}}-e) of a quantity of gas is calculated from its GWP. For any gas, it is the mass of {{CO2}} which would warm the earth as much as the mass of that gas.<ref name="epadef">{{Cite web\|title=CO2e\|url=https://www3.epa.gov/carbon-footprint-calculator/tool/definitions/co2e.html\|archive-url=https://web.archive.org/web/20190724134301/https://www3.epa.gov/carbon-footprint-calculator/tool/definitions/co2e.html\|url-status=dead\|archive-date=July 24, 2019\|access-date=2020-06-27\|website=www3.epa.gov}}</ref> Thus it provides a common scale for measuring the climate effects of different gases. It is calculated as GWP multiplied by mass of the other gas. For example, if a gas has GWP of 100, two tonnes of the gas have {{CO2}}e of 200 tonnes, and 9 tonnes of the gas has {{CO2}}e of 900 tonnes.

	On a global scale, the warming effects of one or more greenhouse gases in the atmosphere can also be expressed as an equivalent atmospheric concentration of {{CO2}}. {{CO2}}e can then be the atmospheric concentration of {{CO2}} which would warm the earth as much as a particular concentration of some other gas or of all gases and aerosols in the atmosphere. For example, {{CO2}}e of 500 parts per million would reflect a mix of atmospheric gases which warm the earth as much as 500 parts per million of {{CO2}} would warm it.<ref name="eea">{{Cite web \|date=2020-02-25 \|title=Atmospheric greenhouse gas concentrations – Rationale \|url=https://www.eea.europa.eu/data-and-maps/indicators/atmospheric-greenhouse-gas-concentrations-6/assessment-1 \|access-date=2020-06-28 \|website=European Environment Agency \|language=en}}</ref><ref name="rmets">{{cite journal \|last1=Gohar \|first1=L. K. \|last2=Shine \|first2=K. P. \|title=Equivalent {{CO2}} and its use in understanding the climate effects of increased greenhouse gas concentrations \|journal=Weather \|date=November 2007 \|volume=62 \|issue=11 \|pages=307–311 \|doi=10.1002/wea.103 \|bibcode=2007Wthr...62..307G \|doi-access=free }}</ref> Calculation of the equivalent atmospheric concentration of {{CO2}} of an atmospheric greenhouse gas or aerosol is more complex and involves the atmospheric concentrations of those gases, their GWPs, and the ratios of their molar masses to the molar mass of {{CO2}}.		On a global scale, the warming effects of one or more greenhouse gases in the atmosphere can also be expressed as an equivalent atmospheric concentration of {{CO2}}. {{CO2}}e can then be the atmospheric concentration of {{CO2}} which would warm the earth as much as a particular concentration of some other gas or of all gases and aerosols in the atmosphere. For example, {{CO2}}e of 500 parts per million would reflect a mix of atmospheric gases which warm the earth as much as 500 parts per million of {{CO2}} would warm it.<ref name="eea">{{Cite web \|date=2020-02-25 \|title=Atmospheric greenhouse gas concentrations – Rationale \|url=https://www.eea.europa.eu/data-and-maps/indicators/atmospheric-greenhouse-gas-concentrations-6/assessment-1 \|access-date=2020-06-28 \|website=European Environment Agency \|language=en}}</ref><ref name="rmets">{{cite journal \|last1=Gohar \|first1=L. K. \|last2=Shine \|first2=K. P. \|title=Equivalent {{CO2}} and its use in understanding the climate effects of increased greenhouse gas concentrations \|journal=Weather \|date=November 2007 \|volume=62 \|issue=11 \|pages=307–311 \|doi=10.1002/wea.103 \|bibcode=2007Wthr...62..307G \|doi-access=free }}</ref> Calculation of the equivalent atmospheric concentration of {{CO2}} of an atmospheric greenhouse gas or aerosol is more complex and involves the atmospheric concentrations of those gases, their GWPs, and the ratios of their molar masses to the molar mass of {{CO2}}.
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	The following [[Units of measurement\|units]] are commonly used:		The following [[Units of measurement\|units]] are commonly used:
	* By the UN climate change panel ([[Intergovernmental Panel on Climate Change\|IPCC]]): billion metric tonnes = n×10<sup>9</sup> [[tonne]]s of {{CO2}} equivalent (Gt{{CO2}}eq)<ref>{{cite journal \|last1=Denison \|first1=Steve \|last2=Forster \|first2=Piers M \|last3=Smith \|first3=Christopher J \|title=Guidance on emissions metrics for nationally determined contributions under the Paris Agreement \|journal=Environmental Research Letters \|date=December 2019 \|volume=14 \|issue=12 \|pages=124002 \|doi=10.1088/1748-9326/ab4df4 \|bibcode=2019ERL....14l4002D \|doi-access=free }}</ref>		* By the UN climate change panel ([[Intergovernmental Panel on Climate Change\|IPCC]]): billion metric tonnes = n×10<sup>9</sup> [[tonne]]s of {{CO2}} equivalent (Gt{{CO2}}eq)<ref>{{cite journal \|last1=Denison \|first1=Steve \|last2=Forster \|first2=Piers M \|last3=Smith \|first3=Christopher J \|title=Guidance on emissions metrics for nationally determined contributions under the Paris Agreement \|journal=Environmental Research Letters \|date=December 2019 \|volume=14 \|issue=12 \|pages=124002 \|doi=10.1088/1748-9326/ab4df4 \|bibcode=2019ERL....14l4002D \|doi-access=free }}</ref>
	* In industry: million metric tonnes of carbon dioxide equivalents (MMTCDE)<ref>{{Cite web \|title=Glossary:Carbon dioxide equivalent – Statistics Explained \|url=https://ec.europa.eu/eurostat/statistics-explained/index.php/Glossary:Carbon_dioxide_equivalent \|access-date=2020-06-28 \|website=ec.europa.eu}}</ref> and MMT {{CO2}}eq.<ref name="epa20">{{Cite web \|date=2020-04-13 \|title=Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990–2018, p. ES-3 \|url=https://www.epa.gov/sites/~~production~~/files/2020-04/documents/us-ghg-inventory-2020-chapter-executive-summary.pdf \|url-status=live \|archive-url=https://web.archive.org/web/20200414000128/https://www.epa.gov/sites/production/files/2020-04/documents/us-ghg-inventory-2020-chapter-executive-summary.pdf \|archive-date=2020-04-14 \|access-date=2020-07-01 \|website=US Environmental Protection Agency}}</ref>		* In industry: million metric tonnes of carbon dioxide equivalents (MMTCDE)<ref>{{Cite web \|title=Glossary:Carbon dioxide equivalent – Statistics Explained \|url=https://ec.europa.eu/eurostat/statistics-explained/index.php/Glossary:Carbon_dioxide_equivalent \|access-date=2020-06-28 \|website=ec.europa.eu}}</ref> and MMT {{CO2}}eq.<ref name="epa20">{{Cite web \|date=2020-04-13 \|title=Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990–2018, p. ES-3 \|url=https://www.epa.gov/sites/default/files/2020-04/documents/us-ghg-inventory-2020-chapter-executive-summary.pdf \|url-status=live \|archive-url=https://web.archive.org/web/20200414000128/https://www.epa.gov/sites/production/files/2020-04/documents/us-ghg-inventory-2020-chapter-executive-summary.pdf \|archive-date=2020-04-14 \|access-date=2020-07-01 \|website=US Environmental Protection Agency}}</ref>
	* For vehicles: grams of carbon dioxide equivalent per mile (g{{CO2}}e/mile) or per kilometer (g{{CO2}}e/km)<ref name="ucs-ev">{{Cite web \|title=How Clean is Your Electric Vehicle? \|url=https://evtool.ucsusa.org/ \|access-date=2020-07-02 \|website=Union of Concerned Scientists \|language=en}}</ref><ref name="rcs">{{Cite web \|last=Whitehead \|first=Jake \|date=2019-09-07 \|title=The Truth About Electric Vehicle Emissions \|url=https://www.realclearscience.com/articles/2019/09/07/the_truth_about_electric_vehicle_emissions_111097.html \|access-date=2020-07-02 \|website=www.realclearscience.com}}</ref>		* For vehicles: grams of carbon dioxide equivalent per mile (g{{CO2}}e/mile) or per kilometer (g{{CO2}}e/km)<ref name="ucs-ev">{{Cite web \|title=How Clean is Your Electric Vehicle? \|url=https://evtool.ucsusa.org/ \|access-date=2020-07-02 \|website=Union of Concerned Scientists \|language=en}}</ref><ref name="rcs">{{Cite web \|last=Whitehead \|first=Jake \|date=2019-09-07 \|title=The Truth About Electric Vehicle Emissions \|url=https://www.realclearscience.com/articles/2019/09/07/the_truth_about_electric_vehicle_emissions_111097.html \|access-date=2020-07-02 \|website=www.realclearscience.com}}</ref>