Large dairy operations tend to have lower green house gas footprints because of more efficient feed conversion.
Ten research papers and one editorial in the International Dairy Journal confirm the dairy industry’s carbon footprint is 2% of the U.S. total.
According to the life-cycle assessment, which looks at carbon emissions all the way from fertilizer production through consumers’ refrigerators, dairy greenhouse gas emissions are estimated to be 2.05 kg carbon dioxide equivalent for every kilogram of fat- and protein-corrected milk.
"This work is noteworthy for its comprehensiveness in looking at every stage of the fluid milk life cycle and for its data collection method," says an editorial which leads off the special Supplement to the April issue of the International Dairy Journal. More than 500 U.S. dairy farms submitted data.
"Based on the amount of milk produced in the United States, the dairy industry accounts for approximately 2% of the total U.S. GHG emissions," says the editorial. This is about a third less than the global dairy industry’s GHG output, which contributes 2.7% of global emissions.
One of the papers included in the Supplement notes that large dairy operations tend to have lower GHG footprints because of more efficient feed conversion. But their use of lagoons for manure storage is one area where losses occur and more efficiency could be gained, if it could be done cost effectively.
The entire set of papers can be found here.