Last reviewed on November 2, 2011 at 10:05

Documentation of California's Greenhouse Gas Inventory (First Edition - Last updated on 11/19/2007)

♦ Category: Agriculture, Forestry and Other Land Use

IPCC: 3A2aii - Livestock - Manure Management - Cattle - Other Cattle
Sector: Agriculture & Forestry : Manure Management : Cattle

♦ Activity: Livestock population - Feedlot - heifers 500+ lbs

♦ Greenhouse gas: Nitrous oxide ( N2O )

► Year 1990 —

● Greenhouse gas emission estimate —

Amount: 131.20 tonnes of N2O Emitted (40,672 tonnes CO2 Eq.)
Basis: Calculation
Calculation: [Livestock population] * [Proportion of livestock in managed system] * [Typical animal mass] * [Nitrogen excretion rate] * [Average number of days per year] * [State weighted N as N2O emission factor] * [Molecular weight ratio of N2O to N2]
Reference: USEPA (2007). Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2005. United States Environmental Protection Agency. EPA 430-R-07-002. and Annex 3.10: Methodology for Estimating CH4 and N2O Emissions from Manure Management. April 15, 2007. Washington DC. http://www.epa.gov/climatechange/emissions/usgginv_archive.html

● Activity level used in calculations —

Activity: Livestock population = 90,433 head of Feedlot - heifers 500+ lbs
Basis: Data
Reference: Wirth, T. (2007). Personal communication between Neva Lowery of CA Air Resources Board and Tom Wirth, Greenhouse Gas Inventory Source Lead, US Environmental Protection Agency, March 2007.

● Parameters and Constants used in calculations —

Parameter: Nitrogen Excretion Rate = 0.3 g / kg / day
Reference: USEPA (2007). Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2005. United States Environmental Protection Agency. EPA 430-R-07-002. and Annex 3.10: Methodology for Estimating CH4 and N2O Emissions from Manure Management. April 15, 2007. Washington DC. http://www.epa.gov/climatechange/emissions/usgginv_archive.html
Parameter: Proportion of livestock in managed system = 1
Reference: Wirth, T. (2007). Personal communication between Neva Lowery of CA Air Resources Board and Tom Wirth, Greenhouse Gas Inventory Source Lead, US Environmental Protection Agency, March 2007.
Parameter: State weighted N as N2O emission factor = 0.0201 g / g
Reference: Wirth, T. (2007). Personal communication between Neva Lowery of CA Air Resources Board and Tom Wirth, Greenhouse Gas Inventory Source Lead, US Environmental Protection Agency, March 2007.
Parameter: Typical animal mass = 420 kg / head
Reference: USEPA (2007). Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2005. United States Environmental Protection Agency. EPA 430-R-07-002. and Annex 3.10: Methodology for Estimating CH4 and N2O Emissions from Manure Management. April 15, 2007. Washington DC. http://www.epa.gov/climatechange/emissions/usgginv_archive.html
Constant: Average number of days per year = 365.2425 day
Reference: USNO (2004). U.S. Naval Observatory, Astronomical Applications Department, Leap Years. Accessed online at: http://aa.usno.navy.mil/faq/docs/leap_years.php
Constant: Molecular weight ratio of N2O to N2 = 1.571133815
Reference: IUPAC (2006). ATOMIC WEIGHTS OF THE ELEMENTS 2005 (IUPAC TECHNICAL REPORT). Pure Appl. Chem., Vol. 78, No. 11, pp. 20512066, 2006.
Constant: Global warming potential of N2O = 310
Reference: IPCC (1996). Second Assessment Report. Climate Change 1995: WG I - The Science of Climate Change. Intergovernmental Panel on Climate Change; J.T. Houghton, L.G. Meira Filho, B.A. Callander, N. Harris, A. Kattenberg, and K. Maskell (eds.); Cambridge University Press. Cambridge, U.K.

● Greenhouse gas emitted per unit activity —

Amount: 1,451 g (i.e. 1.45 kg) of N2O per head of Feedlot - heifers 500+ lbs
449,745 g (i.e. 449.74 kg) of CO2eq. per head of Feedlot - heifers 500+ lbs
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