GlobAl WArminG PotentiAl of Greenhouse GAses
The Global Warming Potential (GWP) of a gas is a measure of
the degree, relative to carbon dioxide, to which the presence of
that gas in the atmosphere will contribute to a long-term increase
in global temperature . The calculation of the GWP for a given
gas takes into account the efficiency of the gas in absorbing solar
radiation (primarily determined by the infrared spectrum of the
compound) and the time the compound will remain in the atmos-
phere before it is removed by natural processes . Thus if a pulse of
1 kg of the gas is emitted to the atmosphere at the same time as a
pulse of 1 kg of CO
2
, the GWP compares the warming effect of the
gas relative to CO
2
over various time horizons .
This table, which is taken from the 2007 report of the
Intergovernmental Panel of Climate Change (IPCC), gives the life-
time in years and the radiative efficiency in watts per square me-
ter for a concentration of one part per billion for the major com-
pounds identified in the Kyoto Protocol as contributing to global
climate change . Radiative efficiency is a measure of the radiative
forcing that influences the energy balance in the Earth–atmos-
phere system . The last four columns of the table give the Global
Warming Potential, first as estimated in 1995 for a 100 year time
horizon, and then as estimated with improved data in 2007 for 20-,
100-, and 500-year horizons . The calculation of a GWP involves a
number of assumptions, and other measures have been proposed
(see Reference) .
The list of compounds includes those identified in the Montreal
Protocol as contributing to ozone depletion, since these com-
pounds also contribute to global warming . It also includes com-
pounds used or proposed as replacements for the ozone-depleting
compounds but which still have global warming potential .
reference
Forster, P ., V . Ramaswamy, P . Artaxo, T . Berntsen, R . Betts, D . W .
Fahey, J . Haywood, J . Lean, D .C . Lowe, G . Myhre, J . Nganga,
R . Prinn, G . Raga, M . Schulz, and R . Van Dorland, 2007: Changes
in Atmospheric Constituents and in Radiative Forcing . In: Climate
Change 2007: The Physical Science Basis . Contribution of Working
Group I to the Fourth Assessment Report of the Intergovernmental
Panel on Climate Change [Solomon, S ., D . Sin, M . Manning, Z .
Chen, M . Marquis, K . B . Averyt, M . Tignor and H .L . Miller (eds .)],
Cambridge University Press, Cambridge, United Kingdom and New
York, NY, USA . Available on the Internet at < http://ipcc-wg1 .ucar .
edu/wg1/wg1-report .html> .
Compound
Synonym/Code
Formula
Lifetime
(years)
Rad. eff.
W m
–2
ppb
–1
GWP for given time horizon
1995
100 yr
Current estimate
20 yr 100 yr 500 yr
Natural atmospheric constituents
Carbon dioxide
CO
2
1 .4×10
–5
1
1
1
1
Methane
CH
4
12
3 .7×10
–4
21
72
25
7 .6
Nitrous oxide
N
2
O
114
3 .03×10
–3
310
289
298
153
Substances controlled by the Montreal Protocol
Trichlorofluoromethane
CFC-11
CCl
3
F
45
0 .25 3800 6730 4750 1620
Dichlorodifluoromethane
CFC-12
CCl
2
F
2
100
0 .32 8100 11000 10900 5200
Chlorotrifluoromethane
CFC-13
CCl
3
F
640
0 .25
10800 14400 16400
1,1,2-Trichloro-1,2,2-trifluoroethane
CFC-113
CCl
2
FCClF
2
85
0 .3 4800 6540 6130 2700
1,2-Dichloro-1,1,2,2-tetrafluoroethane
CFC-114
CClF
2
CClF
2
300
0 .31
8040 10000 8730
Chloropentafluoroethane
CFC-115
CClF
2
CF
3
1700
0 .18
5310 7370 9990
Bromotrifluoromethane
Halon-1301
CBrF
3
65
0 .32 5400 8480 7140 2760
Bromochlorodifluoromethane
Halon-1211
CBrClF
2
16
0 .3
4750 1890
575
1,2-Dibromotetrafluoroethane
Halon-2402
CBrF
2
CBrF
2
20
0 .33
3680 1640
503
Tetrachloromethane
Carbon
tetrachloride
CCl
4
26
0 .13 1400 2700 1400
435
Bromomethane
Methyl bromide
CH
3
Br
0 .7
0 .01
17
5
1
1,1,1-Trichloroethane
Methyl chloroform CH
3
CCl
3
5
0 .06
506
146
45
Chlorodifluoromethane
HCFC-22
CHClF
2
12
0 .2 1500 5160 1810
549
2,2-Dichloro-1,1,1-trifluoroethane
HCFC-123
CHCl
2
CF
3
1 .3
0 .14
90
273
77
24
1-Chloro-1,2,2,2-tetrafluoroethane
HCFC-124
CHClFCF
3
5 .8
0 .22
470 2070
609
185
1,1-Dichloro-1-fluoroethane
HCFC-141b
CH
3
CCl
2
F
9 .3
0 .14
2250
725
220
1-Chloro-1,1-difluoroethane
HCFC-142b
CH
3
CClF
2
17 .9
0 .2 1800 5490 2310
705
3,3-Dichloro-1,1,1,2,2-pentafluoropropane
HCFC-225ca
CHCl
2
CF
2
CF
3
1 .9
0 .2
429
122
37
1,3-Dichloro-1,1,2,2,3-pentafluoropropane
HCFC-225cb
CHClFCF
2
CClF
2
5 .8
0 .32
2030
595
181
Hydrofluorocarbons
Trifluoromethane
HFC-23
CHF
3
270
0 .19 11700 12000 14800 12200
Difluoromethane
HFC-32
CH
2
F
2
4 .9
0 .11
650 2330
675
205
Pentafluoroethane
HFC-125
CHF
2
CF
3
29
0 .23 2800 6350 3500 1100
14-34
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4/11/08 5:25:02 PM
Compound
Synonym/Code
Formula
Lifetime
(years)
Rad. eff.
W m
–2
ppb
–1
GWP for given time horizon
1995
100 yr
Current estimate
20 yr 100 yr 500 yr
1,1,1,2-Tetrafluoroethane
HFC-134a
CH
2
FCF
3
14
0 .16 1300 3830 1430
435
1,1,1-Trifluoroethane
HFC-143a
CH
3
CF
3
52
0 .13 3800 5890 4470 1590
1,1-Difluoroethane
HFC-152a
CH
3
CHF
2
1 .4
0 .09
140
437
124
38
1,1,1,2,3,3,3-Heptafluoropropane
HFC-227ea
CF
3
CHFCF
3
34 .2
0 .26 2900 5310 3220 1040
1,1,1,3,3,3-Hexafluoropropane
HFC-236fa
CF
3
CH
2
CF
3
240
0 .28 6300 8100 9810 7660
1,1,1,3,3-Pentafluoropropane
HFC-245fa
CHF
2
CH
2
CF
3
7 .6
0 .28
3380 1030
314
1,1,1,3,3-Pentafluorobutane
HFC-365mfc
CH
3
CF
2
CH
2
CF
3
8 .6
0 .21
2520
794
241
1,1,1,2,3,4,4,5,5,5-Decafluoropentane
HFC-43-10mee
CF
3
CHFCHFCF
2
CF
3
15 .9
0 .4 1300 4140 1640
500
Perfluorinated compounds
Sulfur hexafluoride
SF
6
3200
0 .52 23900 16300 22800 32600
Nitrogen trifluoride
NF
3
740
0 .21
12300 17200 20700
Tetrafluoromethane
PFC-14
CF
4
50000
0 .10 6500 5210 7390 11200
Hexafluoroethane
PFC-116
C
2
F
6
10000
0 .26 9200 8630 12200 18200
Perfluoropropane
PFC-218
C
3
F
8
2600
0 .26 7000 6310 8830 12500
Perfluorocyclobutane
PFC-318
c-C
4
F
8
3200
0 .32 8700 7310 10300 14700
Perfluorobutane
PFC-3-1-10
C
4
F
10
2600
0 .33 7000 6330 8860 12500
Perfluoropentane
PFC-4-1-12
C
5
F
12
4100
0 .41
6510 9160 13300
Perfluorohexane
PFC-5-1-14
C
6
F
14
3200
0 .49 7400 6600 9300 13300
Perfluorodecalin
PFC-9-1-18
C
10
F
18
>1,000
0 .56
>5500 >7500 >9500
(Trifluoromethyl)sulfur pentafluoride
SF
5
CF
3
800
0 .57
13200 17700 21200
Fluorinated ethers
Trifluoromethyl difluoromethyl ether
HFE-125
CHF
2
OCF
3
136
0 .44
13800 14900 8490
Bis(difluoromethyl) ether
HFE-134
CHF
2
OCHF
2
26
0 .45
12200 6320 1960
Methyl trifluoromethyl ether
HFE-143a
CH
3
OCF
3
4 .3
0 .27
2630
756
230
2-Chloro-2-(difluoromethoxy)-1,1,1-
trifluoroethane
HCFE-235da2
CHF
2
OCHClCF
3
2 .6
0 .38
1230
350
106
Methyl 1,1,2,2-tetrafluoroethyl ether
HFE-245cb2
CH
3
OCF
2
CHF
2
5 .1
0 .32
2440
708
215
2-(Difluoromethoxy)-1,1,1-trifluoroethane
HFE-245fa2
CHF
2
OCH
2
CF
3
4 .9
0 .31
2280
659
200
Methyl pentafluoroethyl ether
HFE-254cb2
CH
3
OCF
2
CHF
2
2 .6
0 .28
1260
359
109
Perfluoropropyl methyl ether
HFE-347mcc3
CH
3
OCF
2
CF
2
CF
3
5 .2
0 .34
1980
575
175
1,1,2,2-Tetrafluoroethyl 1,1,1-trifluoroethyl
ether
HFE-347pcf2
CHF
2
CF
2
OCH
2
CF
3
7 .1
0 .25
1900
580
175
1-Methoxy-1,1,2,2,3,3-hexafluoropropane
HFE-356pcc3
CH
3
OCF
2
CF
2
CHF
2
0 .33
0 .93
386
110
33
Methyl nonafluorobutyl ether
HFE-449sl (HFE-
7100)
C
4
F
9
OCH
3
3 .8
0 .31
1040
297
90
1-Ethoxy-1,1,2,2,3,3,4,4,4-nonafluorobutane HFE-569sf2 (HFE-
7200)
C
4
F
9
OC
2
H
5
0 .77
0 .3
207
59
18
1-(Difluoromethoxy)-2-[(difluoromethoxy)di
fluoromethoxy]-1,1,2,2-tetrafluoroethane
HFE-43-10pccc124
(H-Galden 1040x)
CHF
2
OCF
2
OC
2
F
4
OCHF
2
6 .3
1 .37
6320 1870
569
Bis(difluoromethoxy)difluoromethane
HFE-236ca12
(HG-10)
CHF
2
OCF
2
OCHF
2
12 .1
0 .66
8000 2800
860
1,2-Bis(difluoromethoxy)-1,1,2,2-
tetrafluoroethane
HFE-338pcc13
(HG-01)
CHF
2
OCF
2
CF
2
OCHF
2
6 .2
0 .87
5100 1500
460
Perfluoropolymethylisopropyl ether
PFPMIE
CF
3
OCF(CF
3
)CF
2
OCF
2
OCF
3
800
0 .65
7620 10300 12400
Other compounds - Direct effects
Dimethyl ether
Methyl ether
CH
3
OCH
3
0 .015
0 .02
1
1
<<1
Dichloromethane
Methylene
chloride
CH
2
Cl
2
0 .38
0 .03
31
8 .7
2 .7
Chloromethane
Methyl chloride
CH
3
Cl
1
0 .01
45
13
4
global Warming Potential of greenhouse gases
14-35
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