In the study, researchers followed the journey of a gallon of milk from the beginning of the lifecycle when crops are grown to feed cows; milk is produced and delivered to processors; through processing, packaging and distribution; all the way to the purchase and disposal of the gallon of milk by the consumer. The completion of the study is a significant first step for the dairy industry in a comprehensive, science-based approach to measure and improve its environmental footprint.
The carbon footprint study, together with data from additional studies measuring greenhouse gas (GHG) emissions, helps validate total US dairy GHG emissions are approximately 2 percent of total US emissions. This is far less than earlier figures reported about the global livestock industry that were incorrectly attributed to US dairy, according to Barnes.