Abstract: | Researchers have attributed 15 percent of global methane releases to emissions of methane from enteric fermentation in animals (wild and domestic). Bovines contribute approximately two-thirds of this amount. Since methane is a potent greenhouse gas, this source frequently is a target for emission reductions. However, the existing literature overstates the importance of bovine methane as a greenhouse gas by as much as 800 percent. Estimates to date have focused solely on gas emissions, ignoring the biological and chemical cycling that removes carbon from the atmosphere. The analysis presented here demonstrates the importance of these cycles in assessing the overall greenhouse effect of biological methane sources such as rice production, termites, and bovine animals. Ignoring this cycling results in overemphasizing the role of developing countries' total contributions to climate change. In economic terms, the analysis shows that reducing CO2 emissions from energy use in industrialized countries is more efficient than reducing net greenhouse methane from animal sources. |