Table 13. U.S. Methane Emissions from Anthropogenic Sources, 1990-1998
(Million Metric Tons of Methane)
| Source | 1990 | 1991 | 1992 | 1993 | 1994 | 1995 | 1996 | 1997 | P1998 |
| Energy Sources | |||||||||
| Coal Mining | 4.26 | 4.12 | 3.97 | 3.34 | 3.36 | 3.43 | 2.95 | 3.16 | 3.15 |
| Oil and Gas | 5.70 | 5.92 | 5.99 | 5.97 | 5.99 | 6.08 | 6.10 | 6.25 | 6.27 |
| Stationary Combustion | 0.56 | 0.59 | 0.62 | 0.54 | 0.53 | 0.58 | 0.58 | 0.44 | 0.43 |
| Mobile Sources | 0.25 | 0.23 | 0.24 | 0.24 | 0.24 | 0.25 | 0.24 | 0.24 | 0.24 |
| Total Energy Sources | 10.77 | 10.86 | 10.82 | 10.10 | 10.11 | 10.34 | 9.87 | 10.09 | 10.09 |
| Waste Management | |||||||||
| Landfills | 10.97 | 10.94 | 10.90 | 10.86 | 10.74 | 10.69 | 10.54 | 10.20 | 9.70 |
| Wastewater Treatment | 0.15 | 0.15 | 0.15 | 0.16 | 0.16 | 0.16 | 0.16 | 0.16 | 0.16 |
| Total Waste Management | 11.12 | 11.09 | 11.05 | 11.01 | 10.90 | 10.85 | 10.70 | 10.36 | 9.87 |
| Agricultural Sources | |||||||||
| Enteric Fermentation | 5.17 | 5.30 | 5.39 | 5.47 | 5.62 | 5.62 | 5.47 | 5.42 | 5.41 |
| Animal Waste | 2.57 | 2.67 | 2.69 | 2.71 | 2.77 | 2.78 | 2.68 | 2.79 | 2.83 |
| Rice Paddies | 0.40 | 0.39 | 0.44 | 0.40 | 0.47 | 0.44 | 0.40 | 0.44 | 0.47 |
| Crop Residue Burning | 0.04 | 0.04 | 0.04 | 0.03 | 0.04 | 0.03 | 0.04 | 0.04 | 0.04 |
| Total Agricultural Sources | 8.18 | 8.40 | 8.56 | 8.62 | 8.91 | 8.87 | 8.60 | 8.69 | 8.74 |
| Industrial Processes | 0.12 | 0.11 | 0.12 | 0.12 | 0.13 | 0.13 | 0.13 | 0.13 | 0.13 |
| Total | 30.19 | 30.47 | 30.55 | 29.85 | 30.05 | 30.20 | 29.30 | 29.27 | 28.84 |
|
P = preliminary data. |
|||||||||