AAAR 32nd Annual Conference
September 30 - October 4, 2013
Oregon Convention Center
Portland, Oregon, USA
Abstract View
Ammonia Emissions from Beef, Swine, and Poultry Production Estimated with Process-Based Models
ALYSSA M. MCQUILLING, Peter Adams, Carnegie Mellon University
Abstract Number: 397 Working Group: Remote and Regional Atmospheric Aerosols
Abstract Ammonia plays a key role in the formation of fine particulate matter in the atmosphere. [Ansari, 1998] In the United States, the animal livestock sector contributes up to seventy five percent of national ammonia emissions, with the largest emitters being dairy cattle, beef cattle, swine, and poultry. [USEPA-NEI, 2004] The goal of this work is to better estimate emissions from beef cattle, swine, and poultry using a process-based modeling approach previously developed by Robert Pinder. [Pinder, 2004] Ammonia emissions from livestock production depend strongly on meteorological conditions (e.g. temperature, wind speed, and precipitation), management practices (e.g. stocking density of housing, type of storage, etc.) and manure characteristics (e.g. dry matter and nitrogen content of wastes). Variability in these factors results in literature animal emission factors varying by a factor of 10 for beef cattle and a factor of 15 for swine. Regional and seasonal variations in emissions must therefore be accounted for in emission inventories and chemical transport models. Emissions cannot be measured for all practices and conditions so a model that describes how emissions occur during manure management will be used to estimate ammonia emissions from livestock. Using existing model framework, we can tune our model to predict ammonia emissions from a single farm and animal type. This procedure is repeated for all management practices and animal types, comparing model performance to literature reported emission factors. Our initial results show that a process-based model is able to explain 36% of emission factor variability for beef and 65% for swine housing based on manure characteristics, management practices, and temperature. Additional model evaluation was done using National Air Emissions Monitoring Study (NAEMS) data for swine and poultry. NAEMS was a multi-year measurement campaign conducted at a number of farms throughout the country and monitored many kinds of emissions from the farms.