Replacing rose-tinted spectacles with a high-powered microscope: The historical versus modern carbon footprint of animal agriculture

As natural resources dwindle and concern over climate change increases, should the livestock industry continue to intensify and improve productivity to feed the increasing population, or return to less productive traditional methods? In 1800, each US farm could only produce enough food to feed one other family. In the wake of considerable improvements in productivity, each farmer currently produces enough food to feed an average of 125 other people. As the global population increases to a predicted 9.5 billion people in the year 2050, food requirements will rise by 70% compared with the present day (Food and Agriculture Organization of the United Nations; FAO, 2009). Assuming the present competition for energy, land, and water continues, resources available for agricultural production will decrease with increased population growth. The global livestock industries thus face the challenge of producing suffi cient animal-source foods to meet consumer demand, using a fi nite resource base. The environmental impact of livestock farming is one of the most commonly discussed issues within food production. A lexicon of previously unfamiliar terms including carbon footprint, sustainability, and local food have entered everyday conversation via media articles, blog posts, and restaurant menus. Ethical consumerism, defi ned by Singer and Mason (2006) as an interest in the way in which food is produced, the practices employed, and a concern for low environmental impact, high animal welfare, and optimal worker conditions, is considered to be increasing. As a consequence, popular perceptions of sustainable agriculture appear to be directed towards traditional systems, organic production, or farms that supply only the local geographical area. Although it is widely understood that improving effi ciency reduces expense, resources, and waste, the consumer often considers effi ciency to have negative connotations when applied to large-scale contemporary food production. This article will discuss the effects of advances in productivity and effi ciency in the livestock industries in the United States on the environmental impact and carbon footprint of modern food production.