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Agricultural methane and its role as a greenhouse gas - new Building Block by John Lynch of @oxfutureoffood explains how #methane and carbon dioxide affect the #climate differently and addresses some common areas of confusion. foodsource.org.uk/building-block… 
Here are some key points from our new #methane explainer. Methane is a stronger greenhouse gas than carbon dioxide, molecule for molecule. Methane is an important greenhouse gas, second only to carbon dioxide in terms of its overall contribution to human-driven climate change.
44% of methane emissions from human activity are from agriculture. Of that 44%, roughly one third comes from enteric fermentation, i.e. the digestive processes of ruminant livestock.
Atmospheric #methane concentrations have increased rapidly over the last decade. Increases in agricultural methane could explain some of the increase; however it has not yet been possible to precisely quantify the different source contributions.
Methane breaks down relatively quickly compared to carbon dioxide, which can persist for centuries or longer in the atmosphere. This means that for a steady rate of methane release, the amount of methane in the atmosphere stays at the same level, but does not increase.
However, since #methane has a powerful effect as a greenhouse gas, even relatively small increases in concentration can have a major climate impact, making the recent observations of increasing atmospheric methane highly concerning.
Conversely, because of its short atmospheric lifetime, if we reduce #methane emissions, we expect the atmospheric concentration would fall relatively quickly. Reducing anthropogenic methane emission rates therefore presents an important mitigation opportunity.
