The importance of reduced meat and dairy consumption for meeting stringent climate change targets

For agriculture, there are three major options for mitigating greenhouse gas (GHG) emissions: 1) productivity improvements, particularly in the livestock sector; 2) dedicated technical mitigation measures; and 3) human dietary changes. The aim of the paper is to estimate long-term agricultural GHG emissions, under different mitigation scenarios, and to relate them to the emissions space compatible with the 2 A degrees C temperature target. Our estimates include emissions up to 2070 from agricultural soils, manure management, enteric fermentation and paddy rice fields, and are based on IPCC Tier 2 methodology. We find that baseline agricultural CO2-equivalent emissions (using Global Warming Potentials with a 100 year time horizon) will be approximately 13 Gton CO(2)eq/year in 2070, compared to 7.1 Gton CO(2)eq/year 2000. However, if faster growth in livestock productivity is combined with dedicated technical mitigation measures, emissions may be kept to 7.7 Gton CO(2)eq/year in 2070. If structural changes in human diets are included, emissions may be reduced further, to 3-5 Gton CO(2)eq/year in 2070. The total annual emissions for meeting the 2 A degrees C target with a chance above 50 % is in the order of 13 Gton CO(2)eq/year or less in 2070, for all sectors combined. We conclude that reduced ruminant meat and dairy consumption will be indispensable for reaching the 2 A degrees C target with a high probability, unless unprecedented advances in technology take place.