Methane emissions
Global methane emissions are major part of global greenhouse gas emissions. Methane in the atmosphere has an estimated 100-year global warming potential of 34, meaning that a ton of methane emitted into the atmosphere creates approximately 34 times the atmospheric warming as a ton of carbon dioxide over a period of 100 years.[1] Atmospheric methane concentrations have reached almost two-and-a-half times pre-industrial levels or 3.2 billion tons. Though methane traps far more heat than the same mass of carbon dioxide, it remains in the atmosphere only about a decade, while carbon dioxide potentially warms for a much longer time period assuming no change in rates of carbon sequestration.[2] On a 20-year timescale, a mass of methane is about 85 times more powerful than carbon dioxide at warming the Earth, but on a 100-year timescale, it is projected to be only about 28-34 times more powerful, on the assumption the carbon dioxide will not be sequestered and will continue to warm the earth for decades after the methane is gone.[1]
60 percent of methane emissions are caused by humans and livestock animals, while natural sources such as wetlands cause about 40 percent of methane emissions.[3][4] Human sources include agriculture, especially animal agriculture and rice production, waste, and fugitive emissions from industry including the energy sector. Grazing animals such as cattle and sheep along with other livestock animals cause at least 30 percent of unnatural methane emissions.[3][5] Fugitive emissions from oil, natural gas and coal contributes about 25 to 34 percent of unnatural methane emissions.[3][5] Human waste including landfill and wastewater cause about 18 percent of unnatural methane emissions. Rice production causes about 7 to 20 percent of unnatural emissions.[5] Wetlands make up about 30 percent while natural sources other than wetlands account for about 10 percent.[3] This includes emissions near oil and gas deposits unrelated to human activity, volcanic activity, and emissions by termites.[3]
Sources of atmospheric methane
Abiogenic (a) methane is stored in rocks and soil stems from the geologic processes that convert ancient biomass into fossil fuels.
Biogenic (b) methane is actively produced by microorganisms in a process called methanogenesis.
Anthropogenic
Anthropogenic sources:[6][7][8]
- Industrial agriculture (b), see also: climate change and agriculture[9]
- Enteric fermentation from livestock
- Rice paddies
- Fossil fuels (a), up to 30-45% of atmospheric methane [10]
- Oil extraction
- Coal mining
- Natural gas extraction
- Gas venting (gas)
- Pipeline transport
- Gas leaks
- Municipal solid waste (b)
- Municipal wastewater (b)
Natural sources
Natural sources that have always been a part of the methane cycle include:[11]
- Wetland methane emissions (b)
- Aerobic methane production (b)
- Arctic methane emissions (a), (b)?
- Termite enteric fermentation emissions (b)
With the ongoing draining for agricultural and building areas, wetlands and the associated methane production are on the decline.
National reduction policies
China implemented regulations requiring coal plants to either capture methane emissions or convert methane into CO2 in 2010. According to a Nature Communications paper published in January 2019, methane emissions instead increased 50 percent between 2000 and 2015.[12][13]
In March 2020, Exxon called for tighter methane regulations, which would include detection and repair of leaks, minimization of venting and releases of unburned methane, and reporting requirements for companies.[14]
By country
Country | 1970 | 2012 |
---|---|---|
10,202 | 13,763 | |
1,764 | 2,644 | |
12,857 | 48,527 | |
7 | 13 | |
n.a. | n.a. | |
23,377 | 18,974 | |
24 | 43 | |
84,918 | 88,476 | |
1,318 | 3,426 | |
10 | 23 | |
94,291 | 125,588 | |
9,022 | 8,007 | |
6,398 | 19,955 | |
94 | 227 | |
791 | 3,379 | |
91,305 | 105,142 | |
100 | 109 | |
12,125 | 16,620 | |
14,123 | 9,243 | |
96 | 228 | |
3,461 | 6,983 | |
20 | 31 | |
698 | 1,770 | |
16,509 | 23,231 | |
3,174 | 3,140 | |
5,232 | 4,448 | |
207,737 | 477,077 | |
13 | 19 | |
1,615 | 4,539 | |
9,940 | 11,794 | |
4,613 | 14,957 | |
1,469 | 2,719 | |
46 | 151 | |
20,087 | 35,915 | |
8,286 | 18,516 | |
67,296 | 106,847 | |
12 | 29 | |
28,890 | 85,677 | |
8,043 | 18,364 | |
Channel Islands | n.a. | n.a. |
10,913 | 18,381 | |
781,088 | 1,752,290 | |
36,921 | 67,979 | |
142 | 284 | |
119,583 | 75,336 | |
6,677 | 7,156 | |
2,599 | 2,315 | |
7,803 | 16,266 | |
2,986 | 4,708 | |
13,600 | 8,560 | |
n.a. | n.a. | |
341 | 642 | |
17,963 | 11,902 | |
7,692 | 7,603 | |
149 | 634 | |
16 | 41 | |
3,787 | 6,861 | |
6,621 | 15,786 | |
20,778 | 51,977 | |
2,239 | 3,032 | |
76 | 2,959 | |
1,797 | 2,894 | |
2,208 | 2,235 | |
32,687 | 64,481 | |
30 | 39 | |
416 | 715 | |
9,972 | 8,552 | |
82,882 | 81,179 | |
41 | 99 | |
876 | 3,894 | |
495 | 1,039 | |
3,493 | 5,019 | |
126,692 | 55,721 | |
5,230 | 21,078 | |
3 | 7 | |
5,872 | 8,255 | |
18 | 29 | |
25 | 37 | |
30 | 71 | |
3,217 | 6,877 | |
7,148 | 28,654 | |
542 | 1,421 | |
2,066 | 2,124 | |
2,956 | 4,587 | |
2,552 | 5,844 | |
704 | 3,147 | |
10,395 | 7,135 | |
308 | 359 | |
398,212 | 636,396 | |
126,665 | 223,316 | |
52,013 | 121,298 | |
19,682 | 24,351 | |
10,170 | 14,330 | |
n.a. | n.a. | |
1,301 | 3,416 | |
40,488 | 35,238 | |
821 | 1,316 | |
101,804 | 38,957 | |
362 | 2,115 | |
68,238 | 71,350 | |
12,009 | 28,027 | |
5 | 16 | |
15,007 | 18,983 | |
25,949 | 32,625 | |
n.a. | n.a. | |
21,910 | 12,691 | |
4,561 | 4,291 | |
6,976 | 15,011 | |
3,323 | 3,181 | |
545 | 1,150 | |
1,130 | 1,287 | |
493 | 1,586 | |
29,695 | 18,495 | |
n.a. | n.a. | |
4,584 | 4,806 | |
714 | 1,169 | |
49 | 151 | |
2,033 | 1,396 | |
15,194 | 20,070 | |
3,189 | 4,629 | |
14,317 | 34,271 | |
13 | 52 | |
8,281 | 18,042 | |
98 | 141 | |
2 | 8 | |
3,157 | 6,082 | |
169 | 311 | |
60,999 | 116,705 | |
17 | 30 | |
2,068 | 3,456 | |
n.a. | n.a. | |
6,735 | 6,257 | |
n.a. | n.a. | |
8,486 | 12,012 | |
12,793 | 9,968 | |
75,254 | 80,637 | |
4,004 | 5,097 | |
1 | 3 | |
17,364 | 23,982 | |
20,204 | 19,026 | |
180 | 215 | |
25,054 | 28,658 | |
4,007 | 6,492 | |
5,185 | 6,858 | |
35,196 | 89,782 | |
2 | 12 | |
6,866 | 16,409 | |
4,571 | 16,858 | |
56,503 | 158,337 | |
1 | 1 | |
2,324 | 3,378 | |
948 | 2,143 | |
10,145 | 16,246 | |
13,704 | 19,321 | |
43,211 | 57,170 | |
97,174 | 65,071 | |
6,731 | 12,976 | |
1,277 | 2,406 | |
4,776 | 41,124 | |
32,425 | 25,708 | |
338,496 | 545,819 | |
1,302 | 2,942 | |
63 | 133 | |
n.a. | n.a. | |
17 | 46 | |
31,740 | 62,903 | |
4,605 | 9,928 | |
n.a. | n.a. | |
9 | 24 | |
2,554 | 3,352 | |
658 | 2,386 | |
n.a. | n.a. | |
4,574 | 4,075 | |
2,099 | 2,822 | |
1,631 | 1,449 | |
9,542 | 16,206 | |
32,270 | 63,156 | |
n.a. | n.a. | |
26,509 | 37,208 | |
11,338 | 11,864 | |
26 | 30 | |
28 | 44 | |
n.a. | n.a. | |
23 | 40 | |
31,752 | 96,531 | |
941 | 709 | |
921 | 1,377 | |
10,082 | 10,304 | |
4,878 | 4,900 | |
2,425 | 12,783 | |
2,814 | 5,408 | |
25,218 | 27,994 | |
71,444 | 106,499 | |
412 | 732 | |
2,056 | 5,343 | |
32 | 61 | |
1,596 | 14,789 | |
2,531 | 7,647 | |
32,789 | 78,853 | |
10,821 | 22,009 | |
1 | 6 | |
2 | 3 | |
8,565 | 21,161 | |
74,352 | 68,061 | |
12,873 | 26,120 | |
120,054 | 58,980 | |
594,255 | 499,809 | |
14,524 | 19,549 | |
16,831 | 47,333 | |
128 | 254 | |
35,151 | 58,199 | |
54,145 | 113,564 | |
Virgin Islands (U.S.) | 16 | 47 |
n.a. | n.a. | |
2,205 | 8,940 | |
33,881 | 6,551 | |
8,497 | 8,589 | |
World | 5,305,820 | 8,014,067 |
Removal technology
In 2019, researchers proposed a technique for removing methane from the atmosphere using zeolite. Each molecule of methane would be converted into CO
2, which has a far smaller impact on climate (99% less). Replacing all atmospheric methane with CO
2 would reduce total greenhouse gas warming by approximately one-sixth.[16]
Zeolite is a crystalline material with a porous molecular structure.[16] Powerful fans could push air through reactors of zeolite and catalysts to absorb the methane. The reactor could then be heated to form and release CO
2. At a carbon price of $500/ton, removing one ton of methane would earn $12,000.[16]
See also
References
- Myhre, G., D. Shindell, F.-M. Bréon, W. Collins, J. Fuglestvedt, J. Huang, D. Koch, J.-F. Lamarque, D. Lee, B. Mendoza, T. Nakajima, A. Robock, G. Stephens, T. Takemura and H. Zhang (2013) "Anthropogenic and Natural Radiative Forcing". Table 8.7 on page 714. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.). Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. Anthropogenic and Natural Radiative Forcing
- "Understanding Global Warming Potentials". Retrieved 2019-09-09.
- "Methane, explained". National Geographic. nationalgeographic.com. 2019-01-23. Retrieved 2019-07-25.
- "Global Carbon Project (GCP)". www.globalcarbonproject.org. Retrieved 2019-07-25.
- https://www.globalmethane.org/documents/gmi-mitigation-factsheet.pdf
- "Frequently Asked Questions". Global Methane Initiative. Retrieved 24 February 2015.
- US EPA, OA (23 December 2015). "Overview of Greenhouse Gases". US EPA.
- Global Methane Emissions and Mitigation Initiatives, Global Methane Initiative
- "Agriculture's greenhouse gas emissions on the rise". FAO. Retrieved 2017-04-19.
- "Fossil fuel industry's methane emissions far higher than thought". The Guardian. 2016.
Emissions of the powerful greenhouse gas from coal, oil and gas are up to 60% greater than previously estimated, meaning current climate prediction models should be revised, research shows
- Harvey Augenbraun, Elaine Matthews, and David Sarma. "EDUCATION: GLOBAL METHANE INVENTORY - The Global Methane Cycle". National Aeronautics and Space Administration/Goddard Institute for Space Studies.CS1 maint: multiple names: authors list (link)
- Brooks Hays (29 January 2019). "Regulations haven't slowed China's growing methane emissions". UPI. Retrieved 31 January 2019.
China's methane emissions increased 50 percent between 2000 and 2015
- Miller, Scot M.; Michalak, Anna M.; Detmers, Robert G.; Hasekamp, Otto P.; Bruhwiler, Lori M. P.; Schwietzke, Stefan (January 29, 2019). "China's coal mine methane regulations have not curbed growing emissions". Nature Communications. 10 (1): 303. doi:10.1038/s41467-018-07891-7. PMC 6351523. PMID 30696820.
- Guzman, Joseph (2020-03-03). "Exxon calls for tighter regulations of methane". TheHill. Retrieved 2020-03-04.
- Methane emissions (kt of CO2 equivalent), The World Bank, 2018
- Alexandru Micu (2019-05-21). "One research team proposes swapping atmospheric methane for CO2, and it might be a good idea". ZME Science. Retrieved 2019-07-17.
External links
- "Main sources of methane emissions". What's Your Impact. 2014-03-14. Retrieved 2018-03-06.
- "Greenhouse Gas Emissions - Methane Emissions". EIA. 2011-03-31. Retrieved 2018-03-06.