This paper estimates the total global emissions of methane and nitrous oxide related to livestock in 2010, from 237 countries. It estimates that methane and nitrous oxide from livestock contribute to 9 % of total GHG emissions. The authors analysed a period from 1961-2010 and noted a total increase of emissions from livestock of 51%. Compared to chicken or pork, the paper estimates that beef has a 10 times higher GHG impact.
Following IPCC guidelines (IPCC 2006), we estimate greenhouse gas emissions related to livestock in 237 countries and 11 livestock categories during the period 1961–2010. We find that in 2010 emissions of methane and nitrous oxide related to livestock worldwide represented approximately 9 % of total greenhouse gas (GHG) emissions. Global GHG emissions from livestock increased by 51 % during the analyzed period, mostly due to strong growth of emissions in developing (Non-Annex I) countries (+117 %). In contrast, developed country (Annex I) emissions decreased (−23 %). Beef and dairy cattle are the largest source of livestock emissions (74 % of global livestock emissions). Since developed countries tend to have lower CO2-equivalent GHG emissions per unit GDP and per quantity of product generated in the livestock sector, the amount of wealth generated per unit GHG emitted from the livestock sector can be increased by improving both livestock farming practices in developing countries and the overall state of economic development. Our results reveal important details of how livestock production and associated GHG emissions have occurred in time and space. Discrepancies with higher tiers, demonstrate the value of more detailed analyses, and discourage over interpretation of smaller-scale trends in the Tier 1 results, but do not undermine the value of global Tier 1 analysis.
Caro, D., Davis, S. J., Bastianoni, S., Caldeira, K., 2014, Global and regional trends in greenhouse gas emissions from livestock, Climatic Change, DOI 10.1007/s10584-014-1197-x
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