Meat Eaters Guide: Methodology - Environmental Working Group

Meat Eaters Guide: Methodology
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tributed to post-farmgate activities: http://www.slideshare.net/trufflemedia/dr-gregory-thoma-porks-carbonfootprint.
This study did not however account for methane emissions associated with waste disposal.
51. British Columbia Ministry of Agriculture, Food and Fisheries (http://www.agf.gov.bc.ca/busmgmt/budgets/
budget_pdf/poultry/vibroilr.pdf; ttp://www.agf.gov.bc.ca/busmgmt/budgets/budget_pdf/small_scale/small_
scale_hay_chicken_budget.pdf)
52. This is significantly smaller than average poultry operations in the US of 200,000 birds or more. However,
the emission result was validated by a detailed LCA (US) national poultry study by Pelletier (2008), which
calculated poultry emissions per kg produced to be 2.36 when converted to edible meat (see validation
chart).
53. Penn State College of Agricultural Sciences, Agricultural Research and Cooperative Extension (http://agalternatives.aers.psu.edu/Publications/SmallflockTurkeys.pdf
)
54. See figure 4, p 8. USDA, ERS, The Economic Organization of U.S. Broiler Production / EIB-38
Accessed in November 2010 at http://www.ers.usda.gov/publications/eib38/eib38.pdf
55. Due to rounding errors, the calculations for post-farmgate emissions vary slightly from the post-farmgate
emissions in the Calculation for Total Overall Greenhouse Gas Emissions from Pork Production and Consumption.
56. The sources of emission differ somewhat from Pelletier’s (2009) study, which attributes 80 percent of
greenhouse gas emission sources to feed production. This could partially be explained by the fact that our
analysis separates out transportation of inputs from feed production. The percentage of feed attributed to
GHG emissions is also higher since Pelletier assigns a negative emission value to litter waste – which he
assumes is used as a soil amendment, thus avoiding a portion of the GHG burden of fertilizer production.
57. In Johnson’s et al study 2002 comparing California and Wisconsin dairies, 36 percent and 41 percent
respectively of emissions came from enteric fermentation, while 21 percent and 3 percent came from
methane from manure management. The significant difference in manure-generated CH4 is the storage
method; the California dairy relies primarily on anaerobic lagoons, while the Wisc. model was primarily
manure deposited on pasture. More information on California dairy emissions can be found in: Capper, J.
L., R. A. Cady, and D. E. Bauman. 2009. “The environmental impact of dairy production: 1944 com`pared
with 2007.” Journal of Animal Science 87, no. 6: 2160-2167. Academic Search Complete, EBSCOhost (accessed
Jan. 25, 2011).
58. In Johnson’s et al study (2002) comparing California and Wisconsin dairies, 36 percent and 41 percent
respectively of emissions came from enteric fermentation, while 21 percent and 3 percent came from methane
from manure management. The significant difference in manure-generated CH4 is the storage method;
the California dairy relies primarily on anaerobic lagoons, while the Wisc. model was primarily manure deposited
on pasture. Capper, J. L., R. A. Cady, and D. E. Bauman. 2009. “The environmental impact of dairy
Environmental Working Group Meat Eaters Guide: Methodology 2011