Holos is a whole-farm model and software program that estimates greenhouse gas (GHG) emissions based on information entered for individual farms. The main purpose of Holos is to test possible ways of reducing GHG emissions from farms and is available at no cost to users.
Users can select scenarios and farm management practices that best describe their operation and then adjust these practices to see the effect on emissions. Examples of these adjustments include changing livestock feed, reducing tillage or including perennial forages in rotation.
Once information is entered into the program, Holos estimates carbon dioxide, nitrous oxide and methane emissions. The sources of emissions include enteric fermentation and manure management, cropping systems and energy use. Carbon storage and loss from lineal tree plantings and changes in land use and management are also estimated. The result is a greenhouse gas emission estimate for the whole farm that can help the user identify ways to reduce farm emissions.
Holos is continually being updated with new data and improved features. The most current version of Holos is version 4.0, released March 16, 2022 It is available in both English and French.
Holos 4.0 Installation Package
We welcome feedback from researchers, farmers and industry to help us improve this software. For more information on Holos, please contact Holos@agr.gc.ca.
Related publications
- Little, Shannan, Chaouki Benchaar, Henry Janzen, Roland Kröbel, Emma McGeough, Aaron McPherson, and Karen Beauchemin. 2018. Using whole-farm analysis based on Holos to reduce net greenhouse gas emissions: examples from dairy systems. Presented at American Dairy Science Association Annual Meeting, Knoxville, Tennessee, USA, June 24-27, 2018. (Presentation)
- Little, Shannan M., Chaouki Benchaar, H. Henry Janzen, Roland Kröbel, Emma J. McGeough and Karen Beauchemin. 2017. Demonstrating the effect of forage source on the carbon footprint of a Canadian dairy farm using whole-systems analysis and the Holos model: Alfalfa silage vs. corn silage. Climate 5: 87-105.
- Alemu, A.W., H. Janzen, S. Little, X. Hao, D.J. Thompson, V. Baron, A. Iwaasa, K.A. Beauchemin, R. Kröbel. 2017. Assessment of grazing management on farm greenhouse gas intensity of beef production systems in the Canadian Prairies using life cycle assessment. Agricultural Systems 158: 1-13.
- Guyader, J., S.M. Little, R. Kröbel, C. Benchaar, K.A. Beauchemin. 2017. Comparison of greenhouse gas emissions from corn- and barley-based dairy production systems in Eastern Canada. Agricultural Systems 152: 38-46.
- Alemu, A.W., B.D. Amiro, S. Bittman, D. MacDonald, K.H. Ominski. 2017. Greenhouse gas emission of Canadian cow-calf operations: A whole-farm assessment of 295 farms. Agricultural Systems 151: 73–83.
- Legesse, G. S.M. Little, K.A. Beauchemin, K.H. Ominski, E.J. McGeough, R. Kröbel, D. MacDonald, T.A. McAllister. 2016. A shrinking beef carbon footprint: Comparing greenhouse gas emissions of Canadian beef production between 1981 and 2011. Presented at LCA Food 2016: 10th International Conference on Life Cycle Assessment of Food 2016, Dublin, Ireland, October 19-21, 2016. (Presentation)
- Legesse, G., K. A. Beauchemin, K. H. Ominski, E. J. McGeough, R. Kroebel, D. MacDonald, S. M. Little, T. A. McAllister. 2016. Greenhouse gas emissions of Canadian beef production in 1981 as compared with 2011. Animal Production Science 56(3): 153-168.
- Kröbel, R., Bolinder, M.A., Janzen, H.H., Little, S.M., Vandenbygaart, A.J., Kätterer, T., 2015. Canadian farm-level soil carbon change assessment by merging the greenhouse gas model Holos with the Introductory Carbon Balance Model (ICBM). Agricultural Systems 143: 76–85.
- Little, Shannan, Karen Beauchemin, Chaouki Benchaar, Lilong Chai, Henry Janzen, Roland Kröbel, Emma McGeough, Andrew VanderZaag. 2015. Demonstrating the effect of diet on the carbon footprint of a Canadian dairy scenario using whole-systems analysis and the Holos model: corn silage vs. alfalfa silage. Presented at LCA 15: LCA XV – A Bright Green Future Conference, Vancouver, BC, October 6-8, 2015. (Presentation)
- Alemu, A., Little, S., Hao, X., Iwaasa, A., Baron, V., Chai, L., Janzen, H., Beauchemin, K., Thompson, D., Kröbel, R. 2015. Application of life cycle assessment approach to beef production systems in the Canadian prairies: impacts of grazing management. Presented at LCA 15: LCA XV – A Bright Green Future Conference, Vancouver, BC, October 6-8, 2015. (Presentation)
- Chai, L., Kröbel, R., MacDonald, D., Bittman, S., Beauchemin, K.A., Janzen, H.H., McGinn, S.M., and Vanderzaag, A., 2016. An ecoregion-specific ammonia emissions inventory of Ontario dairy farming: Mitigation potential of diet and manure management practices. Atmospheric Environment 126: 1-14.
- Kröbel, R., Janzen, H.H., Ellert, B.H., Beauchemin, K.A., McAllister, T.A., 2015. Agriculture is neither the culprit nor the solution to Climate Change. "Our common future under climate change" conference, Paris, 7-10 July, 2015. (Poster)
- Chai, L., Kröbel, R., MacDonald, D., Bittman, S., Beauchemin, K.A., Janzen, H.H., McGinn, S., 2015. Developing nitrogen loss fractions for beef and dairy cattle manure storage systems in Canadian ecoregions: a comparison between West and East. Canadian Society for Bioengineering Conference/CSBE/SCGAB 2015 Annual Conference, Edmonton, AB, 5-8 July 2015. (Presentation)
- Chai, L., Kröbel, R., Beauchemin, K.A., MacDonald, D., Janzen, H.H., McGinn, S., Bittman, S., 2015. Greenhouse gases and ammonia emissions from grazing beef cattle in Alberta and Ontario Canada. Canadian Society for Bioengineering Conference/CSBE/SCGAB 2015 Annual Conference, Edmonton, AB, 5-8 July 2015. (Presentation)
- Martel, M., Kröbel, R., Hrapovic, L., Janzen, H., McConkey, B., Glenn, A., and Wilson, H. (2015). "A Canadian water budget model for water footprint assessment of crop production". IUSS-CSSS-AQSSS 2015 Meeting, Montreal, QC, Canada, July 5-10, 2015. (Poster)
- Hünerberg, M., S. M. Little, K. A. Beauchemin, S. M. McGinn, D. O'Connor, E. K. Okine, O. M. Harstad, R. Kröbel and T. A. McAllister. 2014. "Feeding high concentrations of corn dried distillers' grains decreases methane, but increases nitrous oxide emissions from beef cattle production." Agricultural Systems 127: 19-27.
- Kröbel, R. H. Janzen, S. Little, S. Li. 2013. Preliminary Holos model assessment of GHG emissions from crop production in the Black-Brook watershed, NB, during the years 1988 – 1997. Presented at Canadian Society of Soil Science/ Manitoba Soil Science Society/ Canadian Society of Agricultural and Forest Meteorology Joint Meeting, July 22-25, 2013, Winnipeg, Manitoba.
- Beauchemin, K.A., S.M. Little, J. Basarab. 2013. Genetic selection for residual feed intake to reduce GHG emissions from beef production in Canada – Evaluation using farm-based life cycle assessment. Presented at 2013 Greenhouse Gases & Animal Agriculture Conference, Dublin, Ireland, 23-26, 2013.
- McGeough, E.J., S.M. Little, H.H. Janzen, T.A. McAllister, S.M. McGinn and K.A. Beauchemin. 2013. Greenhouse gas emissions from dairying in Eastern Canada – Effects of varying dairy cow replacement rate. Presented at 2013 Greenhouse Gases & Animal Agriculture Conference, Dublin, Ireland, June 23-26, 2013.
- McGeough, E.J., S.M. Little, H.H. Janzen, T.A. McAllister, S.M. McGinn, K.A. Beauchemin. 2013. Greenhouse gas emissions from dairying in Eastern Canada – Effects of varying dairy cow replacement rate. Presented at 2013 Canadian Society of Animal Science(CSAS) - Canadian Meat Science Association (CMSA) Joint Annual Meeting, Banff, Alberta, June 18-20, 2013.
- Hünerberg, M., S.M. Little, K.A. Beauchemin, S.M. McGinn, O.M. Harstad, E.K. Okine, T.A. McAllister. 2013. Farm-based life cycle assessment of greenhouse gas emissions from beef cattle fed dried distillers' grains plus solubles. Presented at 2013 CSAS-CMSA Joint Annual Meeting, Banff, Alberta, June 18-20, 2013.
- Kroebel, R., H.H. Janzen, K.A. Beauchemin, H. Bonesmo, S.M. Little, T.A. McAllister. 2012. "A proposed approach to estimate and reduce the environmental impact from whole farms." Acta Agriculturae Scandinavica, Section A – Animal Science 62(4):225-232.
- Bonesmo, H., S.M. Little, O.M. Harstad, K.A. Beauchemin, A.O. Skelvag, and O. Sjelmo. 2012 "Estimating farm-scale greenhouse gas emission intensity of pig production in Norway." Acta Agriculturae Scandinavica, Section A – Animal Science 62(4):318-325.
- McGeough, E. J., S. M. Little, H. H. Janzen, T. A. McAllister, S. M. McGinn, and K. A. Beauchemin. 2012. "Life cycle assessment of greenhouse gas emissions from dairy production in Eastern Canada: A case study." Journal of Dairy Science, 95:5164-5175.
- Beauchemin, K. A., H. H. Janzen, S. M. Little, T. A. McAllister, S. M. McGinn. February 2012. Estimating the carbon footprint of beef production in western Canada. Bull Breeders. Prairie Post. 36 pages.
- Beauchemin, K.A., H.H. Janzen, S.M. Little, T.A. McAllister and S.M. McGinn. 2011. "Mitigation of greenhouse gas emissions from beef production in western Canada - Evaluation using farm-based life cycle assessment." Animal Feed Science and Technology 166-167: 663-677.
- Beauchemin, K.A., H.H. Janzen, S.M. Little, T.A. McAllister and S.M. McGinn. 2010. "Life cycle assessment of greenhouse gas emissions from beef production in western Canada: A case study." Agricultural Systems 103: 371-379.
- Beauchemin, K.A., H.H. Janzen, S.M. Little, T.A. McAllister and S.M. McGinn. 2010. Mitigation of greenhouse gas emissions from beef production in Canada - Life cycle analysis using Holos. Greenhouse Gases and Animal Agriculture Conference, Banff, Alberta, October 3-8, 2010.
- Little, S.M., K. Maclean and J. Barbieri. 2010. Holos: A tool to estimate and reduce GHGs from farms. The model and the tools. Greenhouse Gases and Animal Agriculture Conference, Banff, Alberta, October 3-8, 2010.
- Reducing methane emissions from livestock. 2010. Agriculture & Agri-Food Canada, Ottawa, Ontario.
- Stewart, A.A. S.M. Little, K.H. Ominski, K.M. Wittenberg and H.H. Janzen. 2009. "Evaluating greenhouse gas mitigation practices in livestock systems: an illustration using the whole-farm approach." Journal of Agricultural Science 147: 367-382.
- Holos: greenhouse gas (GHG) software for farms. 2009. Agriculture & Agri-Food Canada, Ottawa, Ontario.
- Janzen, H.H., R.L. Desjardins, P. Rochette, M. Boehm and D. Worth (Eds). 2008. Better Farming Better Air: A scientific analysis of farming practice and greenhouse gases in Canada. Agriculture and Agri-Food Canada: Ottawa, Canada. 146 pages.
- Little, S.M., J. Lindeman, K. Maclean and H.H. Janzen. 2008. Holos - A tool to estimate and reduce GHGs from farms. Methodology and algorithms for Version 1.1.x. Agriculture & Agri-Food Canada, Ottawa, Ontario, 158 pages.
- Janzen, H. H., D. A. Angers, M. Boehm, M. Bolinder, R. L. Desjardins, J. A. Dyer, B. H. Ellert, D. J. Gibb, E. G. Gregorich, B. L. Helgason, R. Lemke, D. Massé, S. M. McGinn, T. A. McAllister, N. Newlands, E. Pattey, P. Rochette, W. Smith, A. J. VandenBygaart, and H. Wang. 2006. "A proposed approach to estimate and reduce net greenhouse gas emissions from whole farms." Canadian Journal of Soil Science 86: 401–418.