Table 12.5  Methane Emissions, 1980-2005                         (Million Metric Tons of Methane)
Year	Energy Sources						Waste Management			Agricultural Sources					Industrial Processes 6	Total
	Coal Mining	Natural Gas Systems 1	Petroleum Systems 2	Mobile Com- bustion 3	Stationary Com- bustion 4	Total	Landfills	Waste- water Treatment	Total	Enteric Fermen- tation 5	Animal Waste	Rice Cultivation	Crop Residue Burning	Total
1980	3.05	4.25	NA	0.28	0.81	8.39	10.52	0.53	11.05	5.47	3.04	0.48	0.04	9.04	0.13	28.61
1981	2.80	4.86	NA	.27	.82	8.75	10.71	.53	11.24	5.56	2.90	.54	.05	9.05	.14	29.18
1982	3.23	4.89	NA	.27	.88	9.26	10.72	.54	11.26	5.50	2.80	.47	.05	8.81	.10	29.43
1983	3.02	4.85	NA	.27	.86	9.00	10.81	.54	11.36	5.46	2.85	.31	.03	8.66	.11	29.13
1984	3.60	4.95	NA	.27	.86	9.68	10.87	.55	11.41	5.33	2.77	.40	.04	8.55	.11	29.76
1985	3.88	5.00	NA	.26	.84	9.98	10.90	.55	11.45	5.27	2.77	.36	.05	8.45	.11	29.99
1986	3.73	4.88	NA	.26	.82	9.69	10.84	.56	11.40	5.13	2.71	.34	.04	8.22	.10	29.41
1987	4.01	4.98	NA	.25	.80	10.04	11.00	.56	11.56	5.08	2.76	.33	.04	8.21	.11	29.93
1988	3.93	5.13	NA	.25	.83	10.14	10.94	.57	11.51	5.10	2.77	.41	.03	8.31	.12	30.09
1989	3.96	5.29	NA	.25	.86	10.36	10.93	.57	11.51	5.08	2.68	.38	.04	8.18	.12	30.16
1990	4.25	5.60	1.30	.24	.56	11.96	R 10.32	.58	R 10.89	5.20	1.89	.40	.04	7.54	.12	R 30.51
1991	4.10	5.83	1.31	.24	.59	12.06	R 10.01	.59	R 10.60	5.17	1.99	.40	.04	7.59	.11	R 30.36
1992	4.05	5.89	1.27	.23	.62	R 12.05	R 9.89	.59	R 10.48	5.28	2.01	.45	.05	7.79	.12	R 30.44
1993	3.44	5.88	1.21	.23	.54	11.29	R 9.67	.60	R 10.27	R 5.18	2.07	.41	.04	R 7.70	.12	R 29.38
1994	3.51	5.89	1.18	.22	R .51	R 11.32	R 9.28	.61	R 9.89	R 5.32	2.15	.48	.05	R 8.00	.13	R 29.33
1995	R 3.64	5.98	1.17	R .21	R .51	R 11.52	R 8.91	.62	R 9.53	5.41	2.17	.44	.04	R 8.06	.13	R 29.24
1996	R 3.21	6.00	1.15	R .21	R .53	R 11.10	R 8.54	.62	R 9.16	5.30	2.16	.41	.05	7.92	.13	R 28.32
1997	3.50	6.27	1.14	R .21	.44	11.57	R 7.99	.63	R 8.62	5.18	2.29	.45	.05	7.97	.13	R 28.30
1998	3.29	6.26	1.11	R .20	.39	R 11.24	R 7.43	.64	R 8.07	R 5.09	2.33	.47	.05	7.94	.13	R 27.38
1999	R 3.11	6.27	1.04	R .20	R .41	R 11.03	R 7.06	.65	R 7.70	5.10	2.29	.50	.05	7.94	.13	R 26.80
2000	R 2.96	6.57	1.03	R .20	R .43	R 11.20	R 6.75	.65	R 7.41	5.06	2.29	.44	.05	7.85	.13	R 26.57
2001	2.96	6.39	1.03	.20	.38	R 10.95	R 6.42	.66	R 7.08	R 5.00	2.32	.47	.05	7.84	.11	R 25.99
2002	R 2.79	6.70	1.02	R .19	R .39	R 11.09	R 6.38	.67	R 7.04	5.03	2.33	.45	.05	R 7.86	.11	R 26.10
2003	R 2.79	6.66	1.01	R .18	R .41	R 11.05	R 6.47	.67	R 7.14	5.05	2.36	.43	.05	7.88	.11	R 26.18
2004	R 2.93	R 6.73	R .97	.19	R .41	R 11.23	R 6.47	.68	R 7.15	R 4.97	2.38	R .47	.06	R 7.88	.12	R 26.37
2005P	2.85	6.70	.92	.20	.42	11.08	6.77	.69	7.46	5.02	2.41	.47	.05	7.96	.11	26.60
1Natural gas production, processing, and distribution. 6Chemical production, and iron and steel production. 2Petroleum production, refining, and distribution. R=Revised.  P=Preliminary.  NA=Not available.   3Emissions from passenger cars, trucks, buses, motorcycles, and other transport. Notes:  ·  Emissions are from anthropogenic sources.  "Anthropogenic" means produced as the result of human activities, including emissions from agricultural activity and domestic livestock.  Emissions from natural sources, such as wetlands and wild animals, are not included.  ·  Under certain conditions, methane may be produced via anaerobic decomposition of organic materials in landfills, animal wastes, and rice paddies.  ·  Because of the continuing goal to improve estimation methods for greenhouse gases, data are frequently revised on an annual basis in keeping with the latest findings of the international scientific community.  ·  Totals may not equal sum of components due to independent rounding. 4Consumption of coal, petroleum, natural gas, and wood for heat or electricity. Web Page:  For related information, see http://www.eia.doe.gov/environment.html. 5Methane emitted as a product of digestion in animals such as cattle, buffalo, sheep, goats, and camels. Sources:  1990, 1995, and 1998-2005:  Energy Information Administration (EIA), Emissions of Greenhouse Gases in the United States 2005 (November 2006), Table 15.  All Other Data:  EIA, Emissions of Greenhouse Gases in the United States, annual reports and unpublished revisions.