Contribution of milk production to global greenhouse gas emissions An estimation based on typical farms

• Published in: Environmental science and pollution research international Vol. 19; no. 2; pp. 390 - 402
• Main Authors: Hagemann, Martin, Ndambi, Asaah, Hemme, Torsten, Latacz-Lohmann, Uwe
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.02.2012
• Subjects: animals; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Carbon dioxide; Carbon Dioxide - analysis; Carbon Dioxide - metabolism; Dairying - methods; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental Monitoring - methods; farms; Food Handling; Greenhouse Effect; greenhouse gases; issues and policy; life cycle assessment; Methane - analysis; Methane - metabolism; milk; milk production; Models, Biological; Nitrous Oxide - analysis; Nitrous Oxide - metabolism; pollution; Regression Analysis; Research Article; Spain; Uncertainty; Waste Water Technology; Water Management; Water Pollution Control; Spain; Typical dairy farms; Greenhouse gas emissions; ‘Cradle-to-farm-gate’ life cycle assessment; Milk production
• ISSN: 0944-1344; 1614-7499; 1614-7499
• DOI: 10.1007/s11356-011-0571-8

Background, aim and scope Studies on the contribution of milk production to global greenhouse gas (GHG) emissions are rare (FAO 2010) and often based on crude data which do not appropriately reflect the heterogeneity of farming systems. This article estimates GHG emissions from milk production in different dairy regions of the world based on a harmonised farm data and assesses the contribution of milk production to global GHG emissions. Materials, methods and results The methodology comprises three elements: (1) the International Farm Comparison Network (IFCN) concept of typical farms and the related globally standardised dairy model farms representing 45 dairy regions in 38 countries; (2) a partial life cycle assessment model for estimating GHG emissions of the typical dairy farms; and (3) standard regression analysis to estimate GHG emissions from milk production in countries for which no typical farms are available in the IFCN database. Across the 117 typical farms in the 38 countries analysed, the average emission rate is 1.50 kg CO 2 equivalents (CO 2 -eq.)/kg milk. The contribution of milk production to the global anthropogenic emissions is estimated at 1.3 Gt CO 2 -eq./year, accounting for 2.65% of total global anthropogenic emissions (49 Gt; IPCC, Synthesis Report for Policy Maker, Valencia, Spain, 2007). Discussion and conclusion We emphasise that our estimates of the contribution of milk production to global GHG emissions are subject to uncertainty. Part of the uncertainty stems from the choice of the appropriate methods for estimating emissions at the level of the individual animal.