Last reviewed on 06-22-2018

Documentation of California's Greenhouse Gas Inventory (11th Edition - Last updated on 11-06-2019)

♦ Category: Agriculture, Forestry and Other Land Use

IPCC: 3A1ai - Livestock - Enteric Fermentation - Cattle - Dairy Cows
Sector: Agriculture & Forestry : Enteric Fermentation : Cattle

♦ Activity: Livestock population - Dairy replacements 12-24 months

♦ Greenhouse gas: Methane ( CH4 )

► Year 2015 —

● Greenhouse gas emission estimate —

Amount: 33,758 tonnes of CH4 Emitted (843,960 tonnes CO2 Eq.)
Basis: Model
Calculation: Cattle enteric fermentation model
Reference: USEPA (2013). Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2011 U.S. Environmental Protection Agency. Annex 3.10: Methodology for Estimating CH4 Emissions from Enteric Fermentation. ttps://www.epa.gov/sites/production/files/2015-12/documents/us-ghg-inventory-2013-annexes.pdf#https://www.epa.gov/sites/production/files/2015-12/documents/us-ghg-inventory-2013-annexes.pdf

● Activity level used in calculations —

Activity: Livestock population = 513,760 head of Dairy replacements 12-24 months
Basis: Model
Calculation: Cattle life cycle model
Reference: USEPA (2013). Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2011 U.S. Environmental Protection Agency. Annex 3.10: Methodology for Estimating CH4 Emissions from Enteric Fermentation. ttps://www.epa.gov/sites/production/files/2015-12/documents/us-ghg-inventory-2013-annexes.pdf#https://www.epa.gov/sites/production/files/2015-12/documents/us-ghg-inventory-2013-annexes.pdf
Reference: USDA and CDFA, various years. The USDA agriculturlal census provides statewide milking cow populations every five years (2002, 2007, 2012). The milking cow population for intervening years are interpolated from CDFA growth profiles for non-census years. https://www.agcensus.usda.gov/Publications/

● Parameters and Constants used in calculations —

Parameter: Not applicable
Constant: Global warming potential of CH4 = 25
Reference: IPCC (2007). Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Solomon S., Qin D., Manning M., Chen Z., Marquis M., Averyt K.B., Tignor M., and Miller H.L. (eds.). http://www.ipcc.ch/publications_and_data/publications_ipcc_fourth_assessment_report_synthesis_report.htm

● Greenhouse gas emitted per unit activity (derived from values listed above) —

Amount: 65,708 g (i.e. 65.71 kg) of CH4 per head of Dairy replacements 12-24 months
1,642,712 g (i.e. 1.64 tonnes) of CO2eq. per head of Dairy replacements 12-24 months
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