Location: Soil, Water & Air Resources ResearchTitle: Nitric oxide emissions from a central California dairy Author
|Addala, Laxmi Ramya|
Submitted to: Atmospheric Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/8/2013
Publication Date: 5/1/2013
Citation: Hasson, A.S., Ogunjemiyo, S.O., Trabue, S.L., Scoggin, K.D., Ashkan, S., Steele, J., Olea, C., Middala, S., Vu, K., Scruggs, A., Addala, L., Nana, L. 2013. Nitric oxide emissions from a central California dairy. Atmospheric Environment. 70:328-336. Interpretive Summary: Central California is a region that regularly experiences ozone levels that exceed state and federal standards during the summer months. Dairy facilities in central California are a significant source of ozone through the release of volatile organic compounds; however, release of nitric oxides (NOx) from dairies in central California could also potentially increase ozone levels. In a field monitoring program at a central California dairy, levels of NOx were measured and total release of NOx calculated. Based on these calculations, dairies were supplied only a fraction of the total NOx released in the central valley of California. Research results described in this report provides needed air quality information to growers, animal scientists, engineers, and regulatory officials on the impact that dairies have on regional air quality for the San Joaquin Valley of California.
Technical Abstract: Concentrations of nitric oxide (NO) were monitored downwind from a central California dairy facility during 2011 and 2012. NO concentrations at the dairy were significantly higher than the background levels during August 2011, but were indistinguishable from upwind concentrations during January, April and May 2012. A plume model (AERMOD) was used to estimate the flux of NO from the dairy during August 2011 with the assumption that emissions were primarily from animal feed. NO emissions from silage were also directly measured from feed to provide additional insight into the sources. The measurements suggest a NO flux of 0.2 g m-2 hour-1 from the feed during August 2011, and < 1 × 10-3 g m-2 hour-1 during the other field measurement periods. Thus, central California dairy facilities appear to be a small contributor to NOx emissions within the region.