When you hear the words ‘cow farts,’ you probably giggle a little. But bovine flatulence and belches are pumping methane into the atmosphere, and contributing even more greenhouse gas emissions than scientists previously thought. According to new NASA-funded research, estimates of livestock emissions could have been off by around 10 percent.
When we think of greenhouse gases that contribute to climate change, carbon dioxide is typically the first one that comes to mind. But methane – even though it can break down quicker – is around 85 times more powerful in trapping heat. And guess who’s pouring methane into the air? Cows. Three scientists, from the United States Department of Agriculture, Joint Global Change Research Institute, and the United States Department of Energy, reevaluated data employed to calculate 2006 Intergovernmental Panel on Climate Change emissions factors. They created revised emissions factors and discovered livestock methane emissions were 11 percent higher in 2011 than other estimates arrived at using the 2006 guidelines.
The journal Carbon Balance and Management published the research the end of September. Lead author Julie Wolf said in a statement, “In many regions of the world, livestock numbers are changing, and breeding has resulted in larger animals with higher intakes of food. This, along with changes in livestock management, can lead to higher methane emissions.”
The way we deal with cow poop also influences how many emissions enter the air. Using manure as fertilizer on fields yields less methane than storing the poop in pits. Changes like that one have caused global methane emissions to increase by almost 37 percent. Between 2003 and 2011, livestock yielded around one fifth of methane emissions – but they were also responsible for between half and three quarters of the methane emissions increase researchers noted during that time period.