Example
Wetlands, livestock digestion and decomposing food waste can produce this gas.
The catch
Biogenic origin does not make an atmospheric methane release harmless.
Related terms
Methane, Wetland, Anthropogenic methane, Flaring, Fossil methane, Fugitive emissions
In more depth
Biogenic methane, explained.
Biogenic methane warms the climate as strongly as any other methane while it lasts. Mass for mass, methane warms about 80 times as much as CO₂ over 20 years and about 30 times over 100 years, and a molecule from a cow traps heat exactly like one from a gas well.
The difference shows up after it breaks down. Plants drew its carbon from the air recently, so the CO₂ left behind returns what was borrowed, and IPCC metrics give it a slightly lower carbon dioxide equivalent factor than fossil methane. That accounting detail does not make steady emissions harmless. Agriculture is the largest human source of methane, and a constant flow from herds, rice fields and landfills keeps atmospheric concentrations higher than they would otherwise be.