The true extent of agriculture's contribution to national greenhouse gas emissions

• Published in: Environmental science & policy 2014-05, Vol.39, p.1-12
• Main Authors: Bell, M.J., Cloy, J.M., Rees, R.M.
• Format: Article
• Language: English
• Subjects: Agricultural production; Agricultural sector; Agriculture; Agronomy; Agronomy. Soil science and plant productions; Air pollution; Animal, plant and microbial ecology; Applied ecology; Biological and medical sciences; Carbon accounting; Carbon emissions; Communication; Conservation, protection and management of environment and wildlife; Emission inventories; Emissions control; Energy consumption; Farming; Farmlands; Farms; Food; Forestry; Fundamental and applied biological sciences. Psychology; Global warming; Government; Governments; Greenhouse effect; Greenhouse gas emissions; Identification; Inventory; Land; Land use; Land-use change; Legislation; Mathematical analysis; Population; Production; Scotland; United Kingdom
• ISSN: 1462-9011; 1873-6416
• DOI: 10.1016/j.envsci.2014.02.001

•Quantification of agricultural GHG emissions is required under legislation.•Alternative approaches to calculating agricultural GHG inventories were compared.•The Scottish Government and IPCC attribute different emissions to the agricultural sector.•High emissions from agriculture are calculated when land-use change is included.•Agriculture is a greater source of emissions using the Scottish Government approach. The agricultural sector is a significant contributor to greenhouse gas (GHG) emissions, and a growing global population means that agricultural production will remain high if food demands are to be met. Mitigation methods to reduce emissions from this sector are thus required, along with identification and quantification of emission sources, so that the agricultural community can act and measure its progress. International legislation requires the submission of annual reports quantifying GHG emissions from agriculture. The importance of attributing the correct sources of emissions to the agricultural sector is clear; however the current approach taken by the IPCC, and reported to the UNFCCC, omits emissions from soils during agricultural land-use change from its agricultural inventory. This paper questions the IPCC approach, and the attribution of agricultural land-use change emissions to a separate category: ‘Land-use, Land-use change and Forestry’. Here a new approach adopted by the Scottish Government is examined, and compared to IPCC guidelines and national communications submitted to the Department of Energy and Climate Change (DECC) and the UNFCCC. The new Scottish Government approach attributes emissions from both land-use conversion and agricultural land under continuous use to the agricultural sector, in addition to those emissions from livestock and energy use on farms. The extent of emissions attributed to the agricultural sector using the Scottish Government approach is much greater than that using the other approaches-largely resulting from the inclusion of cropland conversion in the Scottish Government calculations. Attribution of these emissions to the agricultural sector gives calculated emissions of 10.63MtCO2eq in 2009, compared to 7.06MtCO2eq using the IPCC guidelines. This has implications for the agricultural community and may influence how and if they choose to act to reduce emissions. A large reduction in emissions from cropland conversion since 1990 means that total agricultural emissions in Scotland have fallen 26.64% when