Livestock production and greenhouse gas emissions: Defining the problem and specifying solutions

Global livestock production contributes an estimated 18% of anthropogenic greenhouse gas (GHG) emissions mainly in terms of methane and nitrous oxide. Enteric fermentation from livestock amounts to 6.2 Gt of CO2 equivalents (4.4% of global emissions). These emissions are coming under scrutiny as countries improve emissions inventories and seek to include more sectors in binding emissions reductions. Global agreements on GHG place no obligations on countries to include agriculture (i.e., livestock) in national inventories or mitigation (emissions reduction) plans. But research suggests a range of cost-effective approaches to reduce emissions from animals including dietary changes and improved productivity through breeding and methods of waste management. Carbon footprinting has been used as a shorthand term to quantify emissions at a range of scales (e.g., the animal, farm, or, more commonly, the entire food chain). Life cycle analysis is a more technical approach to recording the environmental impact to be attributed to final products. Policy incentives can target the farm or actors in product life cycles. Governments typically focus on farms, whereas supermarkets and other retailers focus on product life cycles as a means of engaging with consumer demands for low impact (per product unit) or sustainable products. The growth of meat global consumption has highlighted the need to consider demand or consumption-side management, alongside production-side interventions. Emissions reductions from livestock production in the developing world offer significant synergies and a potential triple win, linking productivity gains, environmental conservation, and poverty alleviation.