http://www.extension.org/67750 Livestock production is the largest source of atmospheric ammonia, accounting for over 50 % and 40 % of the national and global inventories, respectively. At beef feedlots for example, 40 to 60 percent of the fed nitrogen is lost to the atmosphere as ammonia. Once ammonia enters the atmosphere it can convert to an aerosol and travel long distances from the source. Most of this fugitive nitrogen is eventually deposited back to the ground when scavenged from the air by precipitation. Unfortunately, this unintentional nitrogen transport and fertilization is having a negative ecological impact on pristine ecosystems around the globe. Thus, it is not surprising that livestock ammonia is an area of growing public concern and regulatory debate. Perhaps nowhere is ammonia from livestock under greater scrutiny than along the Front Range of Colorado. Increased levels of atmospheric nitrogen deposition are having a negative impact on the ecology of Rocky Mountain National Park, a crown jewel of the National Park System. While studies suggest many different sources are contributing to nitrogen deposition in the park (e.g., urban, out of state sources), much attention has been directed to the beef feedlots and dairies that populate the plains just east of the mountains. The keynote address will briefly discuss ammonia emissions from livestock at global scales, with commentary on a new United Nations report "Our Nutrient World" that draws considerable attention to manure management and atmospheric ammonia. The remainder of the presentation will focus on Colorado's regional ammonia issue and what is being done to reduce ammonia loss from feedlots and dairies along the Front Range. New technologies for measuring ammonia and minimizing environmental impacts will be discussed.