Estimated Sources and Sinks of Methane (Tg CH4 per year)
Sources
Natural
  • Wetlands
    		•

    115

    (100-200)
  • Termites
    		•

    20

    (10-50)
  • Ocean
    		•

    10

    (5-20)
  • Freshwater
    		•

    5

    (1-25)
  • CH4 Hydrate
    		•

    5

    (0-5)
    Anthropogenic
  • Coal Mining, Natural Gas, and Pet. Industry
    		•

    100

    (70-120)
  • Rice Paddies
    		•

    60

    (20-150)
  • Enteric Fermentation
    		•

    80

    (65-100)
  • Animal Wastes
    		•

    25

    (20-30)
  • Domestic Sewage Treatment
    		•

    25

    ?
  • Landfills
    		•

    30

    (20-70)
  • Biomass Burning

    		•

    40

    (20-80)
    Sinks
    Atmospheric {tropospheric & stratospheric} removal

    470

    (420-520)
    Removal by soils

    30

    (15-45)
    Atmospheric Increase

    32

    (28-37)

    Adapted from Houghton, J.T., Climate Change 1982. Cambridge University Press.