South Coast ammonia emissions data draws skepticism

Research and related publicity suggesting both automobiles and dairy cows contribute heavily to southern California’s ammonia air emissions has drawn skepticism from dairy researchers and industry leaders, including Western United Dairymen CERO Michael Marsh and UC Davis air quality specialist Dr. Frank Mitloehner. The study, “Ammonia sources in the California South Coast Air Basin and their impact on ammonium nitrate formation,” was published as a Geophysical Research Letter, a geosciences journal by the American Geophyisical Union (AGU). The airborne measurements were used to estimate automobile NH3 emissions (62 metric tons/day, plus or minus 24 metric tons/day), and dairy facility NH3 emissions (33 to 176 metric tons/day, plus or minus 16-88 metric tons/day). The Los Angeles Times reported on the study, framing it as clear proof that cows contribute heavily to air pollution in Southern California. (more) May 17, 2012 Dairy Profit Update