Last reviewed on 12-01-2023

Documentation of California's Greenhouse Gas Inventory (2023 Edition - Last updated on 12-1-2023)

♦ Category: Agriculture, Forestry and Other Land Use

IPCC: 3A1f - Livestock - Enteric Fermentation - Horses
Sector: Agriculture & Forestry : Enteric Fermentation : Other Livestock

♦ Activity: Livestock population - Horses

♦ Greenhouse gas: Methane ( CH4 )

► Year 2011 —

● Greenhouse gas emission estimate —

Amount: 13,868 tonnes of CH4 Emitted (346,706 tonnes CO2 Eq.)
Basis: Calculation
Calculation: [Livestock population] * [CH4 emission factor]
Reference: IPCC (2006). 2006 IPCC Guidelines for National Greenhouse Gas Inventories, Prepared by the National Greenhouse Gas Inventories Programmed, Eggleston HAS., Biennia L., Miwa K., Negara T. and Tanabe K. (eds). Vol.4, Chap. 10: Livestock and Manure Management. Published: IGES, Japan. http://www.ipcc-nggip.iges.or.jp/public/2006gl/pdf/4_Volume4/V4_10_Ch10_Livestock.pdf

● Activity level used in calculations —

Activity: Livestock population = 770,457 head of Horses
Basis: Calculation
Calculation: [US Horse Population] * [Ratio of California to US horse population]
Reference: CARB (2016). Technical support document on GHG inventory methodologies for the 2000-2014 inventory. See Discussion of emissions from enteric fermentation available at: https://ww3.arb.ca.gov/cc/inventory/pubs/reports/2000_2014/ghg_inventory_00-14_technical_support_document.pdf
Reference: Not Applicable.

● Parameters and Constants used in calculations —

Parameter: CH4 emission factor = 18,000 g / individual
Reference: IPCC (2006). 2006 IPCC Guidelines for National Greenhouse Gas Inventories, Prepared by the National Greenhouse Gas Inventories Programmed, Eggleston HAS., Biennia L., Miwa K., Negara T. and Tanabe K. (eds). Vol.4, Chap. 10: Livestock and Manure Management. Published: IGES, Japan. http://www.ipcc-nggip.iges.or.jp/public/2006gl/pdf/4_Volume4/V4_10_Ch10_Livestock.pdf
Parameter: Ratio of California to US horse population = 0.0759
Reference: AHC (2005). American Horse Council. National Economic Impact of the U.S. Horse Industry. Report available at: http://horsecouncil.org/
Parameter: US horse population = 10,150,000 head
Reference: FAO (2012). FAOSTAT Statistical Database. Food and Agriculture Organization of the United Nations. Available online at: http://faostat.fao.org
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: 18,000 g (i.e. 18 kg) of CH4 per head of Horses
450,000 g (i.e. 450 kg) of CO2eq. per head of Horses