Dairy's Carbon Footprint: Flatulence Tops the List

In 2007, Americans consumed approximately 17.4 million metric tons of fluid milk -- milk consumed as a drink or with cereal, rather than milk used in dairy products such as cheese, yogurt and ice cream. The dairy industry has set a goal of 25 percent reduction in greenhouse gas emissions by 2020.
http://www.sciencedaily.com/releases/2013/05/130531101724.htm