A recent study by McGee (Agriculture and Human Values, 32, 255–263, 2015) from the University of Oregon has led to discussions in international media and on the web. This study addresses an interesting question and applies advanced statistics for its analysis. However, we identify several methodological flaws that invalidate the results. First, McGee tests a hypothesis that does not correspond to his main question and which does not allow McGee to derive the conclusions that are drawn in his paper and reported in the media coverage. Second, the data used are not adequate for the analysis because: i) the dependent variable does not reflect the greenhouse gas emissions characteristics of organic agriculture (e.g. different emission factors in organic and conventional agriculture or avoidance of emissions from fertilizer production), ii) the explanatory variables neglect the livestock sector, and iii) trade aspects are missing. Third, McGee fails to discuss his findings in the light of quite a substantial body of experimental, bio-physical research from the US and elsewhere.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Price excludes VAT (USA)
Tax calculation will be finalised during checkout.
Aguilera, E., L. Lasaletta, A. Gattinger, and B. Gimeno. 2013. Managing soil carbon for climate change mitigation and adaptation in Mediterranean cropping systems: A meta-analysis. Agriculture, Ecosystems and Environment 168(168): 25–36.
Aguilera, E., G. Guzmán, and A. Alonso. 2015a. Greenhouse gas emissions from conventional and organic cropping systems in Spain. I. Herbaceous crops. Agronomy for Sustainable Development 35(2): 713–724.
Aguilera, E., G. Guzmán, and A. Alonso. 2015b. Greenhouse gas emissions from conventional and organic cropping systems in Spain. II. Fruit tree orchards. Agronomy for Sustainable Development 35(2): 725–737.
Beck, N. 2008. Time-series cross-section methods. In The Oxford Handbook of Political Methodology, ed. J. Box-Steffensmeir, H. Brady, and D. Collier, 475–493. London: Oxford University Press.
Deaton, A., and J. Muellbauer. 1980. An almost ideal demand system. The American Economic Review 70(3): 312–326.
Gattinger, A., A. Muller, M. Haeni, C. Skinner, A. Fließbach, N. Buchmann, P. Mäder, M. Stolze, P. Smith, N.E.-H. Scialabba, and U. Niggli. 2012. Enhanced top soil carbon stocks under organic farming. Proceedings of the National Academy of Sciences 109(44): 18226–18231.
Kesse-Guyot, E., S. Péneau, C. Méjean, F. Szabo de Edelenyi, P. Galan, S. Hercberg, and D. Lairon. 2013. Profiles of organic food consumers in a large sample of French adults: Results from the nutrinet-santé cohort study. PLoS One 8: e76998. doi:10.1371/journal.pone.0076998.
Kong, A.Y., S. Fonte, C. van Kessel, and J. Six. 2007. Soil aggregates control N cycling efficiency in long-term conventional and alternative cropping systems. Nutrient Cycling in Agroecosystems 79(1): 45–58.
MailOnline. 2015. Is organic farming making climate change worse? Demand for ‘sustainable’ food has increased greenhouse gas emissions, by Richard Grey, Wednesday 15 July. http://www.dailymail.co.uk/sciencetech/article-3162733/Is-organic-farming-making-climate-change-worse-Demand-sustainable-food-increased-greenhouse-gas-emissions.html. Accessed 30 July 2015.
Marsh, T.L. 2005. Economic substitution for US wheat food use by class. Australian Journal of Agricultural and Resource Economics 49(3): 283–301.
McGee, J. 2015. Does certified organic farming reduce greenhouse gas emissions from agricultural production? Agriculture and Human Values 32(2): 255–263. doi:10.1007/s10460-014-9543-1.
Robertson, G.P., E.A. Paul, and R.R. Harwood. 2000. Greenhouse gases in intensive agriculture: Contributions of individual gases to the radiative forcing of the atmosphere. Science 289(5486): 1922–1925.
Skinner, C., A. Gattinger, A. Muller, P. Mäder, A. Fliessbach, R. Ruser, M. Stolze, and U. Niggli. 2014. Greenhouse gas fluxes from agricultural soils under organic and non-organic management—a global meta-analysis. Science of the Total Environment 468–469: 553–563.
Stehfest, E., L. Bouwman, D.P. van Vuuren, M.G.J. den Elzen, B. Eickhout, and P. Kabat. 2009. Climate benefits of changing diet. Climatic Change 95: 83–102. doi:10.1007/s10584-008-9534-6.
Teasdale, J.R., C.B. Coffman, and R.W. Mangum. 2007. Potential long-term benefits of no-tillage and organic cropping systems for grain production and soil improvement. Agronomy Journal 99(5): 1297–1305.
The Guardian. 2015. Organic farms don’t have the tiny carbon footprint they like to tout. But they could by Julius McGee, Tuesday 21 July. http://www.theguardian.com/commentisfree/2015/jul/21/organic-farms-carbon-footprint-climate-change. Accessed 30 July 2015.
Tilman, D., and M. Clark. 2014. Global diets link environmental sustainability and human health. Nature 515:518–522. doi: 10.1038/nature13959 http://www.nature.com/nature/journal/v515/n7528/abs/nature13959.html#supplementary-information.
UoO. 2015. Study suggests organic farming needs direction to be sustainable, University of Oregon, Sunday, 12 July. https://around.uoregon.edu/content/study-suggests-organic-farming-needs-direction-be-sustainable. Accessed 30 July 2015.
Venkat, K. 2012. Comparison of twelve organic and conventional farming systems: A life cycle greenhouse gas emissions perspective. Journal of Sustainable Agriculture 36: 620–649. doi:10.1080/10440046.2012.672378.
York, R. 2012. Do alternative energy sources displace fossil fuels? Nature Climate Change 2(6): 441–443.
Zhang, W.-F., Z. Dou, P. He, X.T. Ju, D. Powlson, D. Chadwick, D. Norse, Y.-L. Lu, Y. Zhang, L. Wu, X.-P. Chen, K.G. Cassman, and F.-S. Zhang. 2013. New technologies reduce greenhouse gas emissions from nitrogenous fertilizer in China. Proceedings of the National Academy of Sciences of the United States of America 110: 8375–8380. doi:10.1073/pnas.1210447110.
The authors would like to thank the Mercator Foundation Switzerland for funding earlier and current work on this subject through the projects “Carbon Credits for Sustainable Land Use Systems (CaLas)” and “The Potential of Sustainable Land-Use Systems to Promote Adaptation to Climate Change.”
Rights and permissions
About this article
Cite this article
Muller, A., Aguilera, E., Skinner, C. et al. Does certified organic farming reduce greenhouse gas emissions from agricultural production? Comment on the McGee study. Agric Hum Values 33, 943–947 (2016). https://doi.org/10.1007/s10460-016-9706-3
- Organic farming
- Greenhouse gas emissions