Summary/Abstract
We estimate greenhouse gas emissions due to the production of beef cattle, pork and chickens for the period 1961–2010, following IPCC guidelines. We find that during the last 50 years, global greenhouse gas (GHG) emissions released from beef cattle, pork and chickens increased by 59 %, 89 % and 461 % respectively. In 2010, GHG emissions caused by beef cattle contributed 54 % of total livestock emissions; pork and chickens contribute to 5–1 %, respectively. In the same year, the methane emissions released from beef cattle represent about 69 % of total emissions associated with that livestock category, in particular due to methane emissions from enteric fermentation. Although beef cattle and pork emissions increased during the period 1961–2010, their respective per capita emissions decreased over the time (−29 % and −15 %, respectively). Beef cattle, especially in developing countries, represent the largest source of livestock-related emissions. For this reason, dietary substitution of pork and chicken products with beef products might be an option for mitigating livestock emissions. However, this is in contrast to the global trend towards increased reliance on cattle.