Long-term trends in the greenhouse gas emissions from the Canadian dairy industry

Abstract

. 2008. Long term trends in the greenhouse gas emissions from the Canadian dairy industry. Can. J. Soil Sci. 88: 629Á639. Estimates of the efficiency of mitigation measures on reducing greenhouse gas (GHG) emissions from the agricultural sector are required. In this paper, recently calculated dairy GHG emissions for 2001 were extrapolated back to 1981 for census years using an index. The index was verified by comparing it with estimates based on the Intergovernmental Panel on Climate Change (IPCC) methodology for 1991. The index agreed with the IPCC estimates within 1% for methane and 4% for nitrous oxide on a national scale with no region having a difference of more than 5% for methane. For nitrous oxide, all regions were within 10%, except British Columbia, where the index was 19% too high. The index indicates that GHG emissions from primary milk production within the Canadian dairy industry have decreased by about 49% since 1981, mainly due to a 57% reduction in the dairy cow population during that period. The GHG emissions per kilogram of milk decreased by 35%, that is from 1.22 kg CO 2 eq kg(1 milk to 0.91 kg CO 2 eq kg (1 milk. Because this study took into account the energy-related CO 2 emissions from all the major farm inputs (fertilizer and fossil fuel), there was little risk of hidden GHG emissions in the emission intensity calculation. This study demonstrates that where lack of input data restricts historical application of simulation models, a semi-empirical index approach can yield valuable results.

Greenhouse gas emissions of Canadian beef production in 1981 as compared with 2011

“…Emissions associated with culled dairy cows for 2011 were estimated using relevant coefficients developed for the allocation of GHG emissions to meat and milk in Canada (McGeough et al 2012). According to Dyer et al (2008), between 1981 and 2001, Canadian milk production increased by 48%, while GHG emission intensity decreased by 35%. On the basis of this, the coefficients derived from McGeough et al (2012) were multiplied by a factor of 1.04 for slaughtered dairy cows in 1981.…”

Carbon Footprint of Beef Cattle

“…Subsequently however, the International Dairy Federation [38] suggests that about 15% of these emissions are attributable to the beef sector. Assuming this allocation of emissions from the dairy sector [18,39] increased the mean beef carbon footprint for Canada by about 5% (Table 2c). On a regional basis, inclusion of emissions allocated from the dairy sector can have a very different impact on the carbon footprint.…”

District Scale GHG Emission Indicators for Canadian Field Crop and Livestock Production

“…Live weights: Unlike the mid-life live weights used to calculate feed consumption in the original ULICEES calculations [8][9][10][11][12][13], Dyer et al [18] found that the live weights used to calculate protein production had to reflect the weights at the time of slaughter. Feedlot operators feed cattle destined for slaughter to a target weight of around 635 kilograms [25].…”

“…ULICEES calculates the emissions of CH 4 , N 2 O, and fossil CO 2 from livestock production in Canada [6]. ULICEES has defined the GHG emission budgets for beef, dairy, pork, poultry, and sheep [8][9][10][11][12][13]. ULICEES calculations have also been used to assess the competition for land between cattle and biodiesel feedstock production [14,15], and between livestock feed production and food or industrial crop production [16], the benefit of eco-grazing sheep and cattle [17], comparing the carbon footprints of plant and livestock protein [7], and the protein-based carbon footprints of different livestock types [18].…”