The global livestock sector supports about 1.3 billion producers and retailers around the world, and is a significant global economic contributor. A new review, published in Nature Climate Change, estimates that livestock could account for up to half of the mitigation potential of the global agricultural, forestry, and land-use sectors, which are the second largest source of emissions globally, after the energy sector.
The researchers estimate that agriculture, forestry, and other land use is responsible for approximately one quarter of global greenhouse gas emissions. According to the new study, livestock production is responsible for 5.6 to 7.5 gigatons of CO2 equivalent per year, or approximately 14 per cent of total anthropogenic emissions.
The international research team says that this new account of the mitigation potential for the global livestock sector is the most comprehensive analysis to date, as it considers both the supply and demand sides of the industry. It shows that for the livestock mitigation to be most effective it needs to be part of a comprehensive effort across the agricultural, forestry, and land use sectors. Additionally, the study finds that sustainable and healthy levels of livestock product consumption in human diets are a crucial part of this mitigation potential.
“Livestock has a role in a healthy and sustainable diet, and the sector has an important economic and social role, particularly in developing countries,” says Mario Herrero, a researcher at the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Australia who led the study in collaboration with the International Institute for Applied Systems Analysis (IIASA) and other research institutes. “We need to balance the optimal levels of consumption to achieve good health outcomes and maintain the economic and social benefits, while also capitalising on the mitigation potential the livestock sector offers.”
Sustainably intensifying livestock production is one way to maintain production levels while capitalising on the mitigation potential of the agricultural sector. The analysis, which provided a comprehensive review of research to date, shows that policies targeting the livestock sector could potentially reduce greenhouse gas emissions by 1.8 gigatons of CO2 equivalent per year, at a carbon price of 100 USD per ton of CO2. In order to go further, however, the researchers say that changes in consumption and a focus on land-use change emissions would be required.
“Regional environmental constraints could still prevent bridging the greenhouse gas efficiency gap, and from the global perspective, the desirable solution may be to relocate part of the production to highly efficient systems, which can be found for example in Europe,” says Petr Havlík, researcher at the IIASA and co-author of the study. “The large differences in regional greenhouse gas intensities may lead to a global increase in emissions if restrictive policies are implemented in more efficient regions.”
“We currently have a strong global drive for curbing global emissions following last year’s Paris agreement. This study shows that livestock should be high on the climate mitigation agenda,” adds IIASA researcher Hugo Valin, who also worked on the study.
The research was published in April 2016 in Nature Climate Change and carried out in partnership between CSIRO, IIASA, CGIAR Climate Change Agriculture and Food Security Research Programme, Colorado State University, the University of Aberdeen, Chalmers University of Technology, Pennsylvania State University, FAO, Wageningen University, Karlsruhe Institute of Technology, the International Livestock Research Institute, University of Oxford, the PBL Netherlands Environmental Assessment Agency.
Herrero M, Henderson B, Havlík P, Thornton PK, Conant RT, Smith P, Wirsenius S, Hristov AN, Gerber P, Gill M, Butterbach-Bahl K, Valin H, Garnett T, and Stehfest E (2016) Greenhouse gas mitigation potentials in the livestock sector. Nature Climate Change. DOI: 10.1038/NCLIMATE2925