This document provides an overview of animal agriculture's contribution to greenhouse gas emissions in the United States. It discusses the US EPA inventory of greenhouse gases and how carbon footprints are calculated through life cycle assessments considering inputs, outputs, and environmental impacts over the full life cycle. The document notes that carbon footprints can vary depending on boundaries, assumptions, and units of measurement used. It also describes how carbon footprints are used to analyze supply chains, conduct geographical and historical comparisons, compare products and management practices, and evaluate tools to estimate emissions.

1. Animal Agriculture’s
Contribution to Greenhouse
Gas Emissions

2. Outline
• U.S. inventory of greenhouse gases
• Carbon Footprint - Life Cycle Assessment
• How they are calculated
• Why they vary
• How they are used

3. US Greenhouse Gas Emissions
EPA 2013

4. Agriculture Sources
Energy use
15%
Enteric
fermentation
28%
Manure
management
14%
Rice cultivation
1%
Burning of
residue
0%
Cropland soils
30%
Grassland
soils
12%
Adapted from Archibeque, S. et al., 2012.

5. Animal Agriculture GHG Emissions
USDA 2011

6. HOW DO WE FIND A CARBON FOOTPRINT?
Life Cycle Analysis (LCA)

7. What is a carbon footprint?
• Total GHG emissions for a given person, place, event, or
product
• Created using a Life Cycle Analysis (LCA)
"Compilation and evaluation of the inputs, outputs and the
potential environmental impacts of a product system
throughout its life cycle“ (ISO 2006)
• Extraction and treatment of raw materials
• Product manufacturing
• Transport and distribution
• Product use
• End of life

8. ISO 2006
How a carbon footprint is created:
Life Cycle Assessment (LCA)

9. Not all analysis come up with the same
“answer”…
0.7 1.0 1.35
2.05

10. WHY DO FOOTPRINTS VARY?

11. Boundaries
• Boundary definition
• Cradle – to – grave
• EPA: only manure management
• Cradle – to – farm gate
Manure
GHGs
Inputs
GHGs
GHGs
GHGs
GHGs
Use &
Disposal
GHGs

12. Thoma et al. 2012
Assumptions
“Generic”
Dairy Carbon
Footprint

13. Units
Capper 2009
Per cow Per gallon of milk
• Per cow
• Per gallon (kg) of milk
• Per gallon (kg) of energy corrected milk (ECM)
• Fat and protein

14. HOW ARE FOOTPRINTS USED?

15. Pork Carbon Footprint Thoma et al. 2011
Supply Chain Analysis

16. Innovation Center for
U.S. Dairy 2010
Supply Chain Analysis

17. Geographical Comparisons
Regional
Dairy Carbon
Footprints
Thoma et al.
2012

18. Historical comparisons
0
5
10
15
20
25
dairy beef
kgCO2eq/kgproduct
1944/1977
2007
Capper et al. 2009, 2011

19. Product Comparisons
EWG 2011

20. Benbrook et al. 2010
0
0.2
0.4
0.6
0.8
1
1.2
Intensive + rBST Conventional Intensive, Organic Grass-based,
Jersey
Manure
Enteric
kgCO2eq/kgECM
Systems comparisons
Dairy Type

21. Management comparisons
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
slurry open storage enclosed storage anaerobic digester
kgCO2eq/kgECM
Rotz 2010
no-till solids separation, tillage incorporation
Dairy Manure Management options

22. Available Carbon Footprint Tools
• DairyGEM – Gas Emissions Model
• Basic tool to evaluate feed and manure
management options
• http://www.ars.usda.gov/Main/docs.htm?docid=213
45
• Shades of Green (SOG) Dairy Calculator
• More advanced tool looks at feed, manure, fertility,
health, and economic return, multiple environmental
factors, currently only methane
• http://www.organic-center.org/sog.download.html

23. More Carbon Footprint Tools
• Live Swine Carbon Footprint Calculator
• http://www.pork.org/Resources/1220/CarbonFootprintCalculatorHome
page.aspx#.UHg2K66s971
• Poultry Carbon Footprint Estimation Toolkit
• https://www.uspoultry.org/uspforms/cdrom/CarbonFootprint/start.cfm
• Cool Farm Tool
• All species
• Includes emissions from fields, inputs, livestock, land use and land use
change and primary processing
• http://www.unilever.com/aboutus/supplier/sustainablesourcing/tools

24. Outline
• U.S. inventory of greenhouse gases
• Carbon Footprint - Life Cycle Assessment
• How they are calculated
• Why they vary
• How they are used

25. For a full list of references cited in this presentation, please visit:
www.animalagclimatechange.org
This project was supported by Agricultural and Food Research Initiative Competitive Grant
No. 2011-67003-30206 from the USDA National Institute of Food and Agriculture.

26. Graphic Sources
U.S. EPA. 2013. “Inventory of U.S. Greenhouse Gas Emissions and Sinks:
1990-2011.”
Archibeque et al., 2012. “Greenhouse Gas Mitigation Opportunities for
Livestock Management in the United States.”
USDA. 2011. U.S. Agriculture and Forestry Greenhouse Gas Inventory:
1990-2008.
ISO 14040:2006. Environmental management - Life cycle assessment -
Principles and framework

27. Graphic Sources
U.S. EPA. 2010. “Inventory of U.S. Greenhouse Gas Emissions and Sinks:
1990-2008”
UN-FAO 2010. “Greenhouse Gas Emissions from the Dairy Sector: A Life
Cycle Assessment”
Capper, J. L., R. A. Cady and D. E. Bauman (2009) “The Environmental Impact
of Dairy Production, 1944 vs 2007.” J. An Sci. 2009.87:2160-2167
Thoma et al. 2010. ”Greenhouse Gas Emissions of Fluid Milk in the U.S.”
Thoma et al. 2012. International Dairy Journal (2012) 1-12
“Greenhouse gas emissions from milk production and consumption in
the United States: A cradle-to-grave life cycle assessment circa 2008”
Capper, J. L., R. A. Cady and D. E. Bauman (2009) “The Environmental
Impact of Dairy Production, 1944 vs 2007.” J. An Sci. 2009.87:2160-2167
Thoma et al. 2011. “National Life Cycle Carbon Footprint Study for
Production of US Swine.”

28. Graphic Sources
Capper, J. L., R. A. Cady and D. E. Bauman. 2009. “The Environmental
Impact of Dairy Production, 1944 vs 2007.” J. An Sci. 2009.87:2160-
2167
Capper, J.L. 2011. “The environmental impact of beef production in the
United States: 1977 compared with 2007.” J. An Sci. 2011.89:4249-4261
Innovation Center for U.S. Dairy. 2010. “Greenhouse Gas LCA for Fluid
Milk”
Thoma et al. 2012. “Regional analysis of greenhouse gas emissions
from USA dairy farms: A cradle to farm-gate assessment of the
American dairy industry circa 2008”

29. Graphic Sources
Environmental Working Group. 2011. “Meat Eater’s Guide to Climate
Change + Health”
Benbrook et al. 2010. “A Dairy Farm’s Footprint: Evaluating the Impacts
of Conventional and Organic Farming Systems”
Rotz, C.A., Montes, F., Chianese, D.S. 2010. The carbon footprint of
dairy production systems through partial life cycle assessment. Journal
of Dairy Science. 93(3):1266-1282.