|
|
Which contributes
more to global warming?
|
|
|
According to the Food & Agriculture Organisation of the
United Nations, livestock contribute more to global warming
than transport, producing 18% of all global greenhouse gas emissions.
(1)
The FAO calculation of livestock's impact on global warming
is wide-ranging and includes both direct and indirect effects,
that is, emissions directly resulting from animals, as well
as "the environmental effects of land use changes and production
of feed crops animals consume."(2)
The calculation includes nitrogen fertilizer production and
nitrogen fertilizer application, and indirect fertilizer emission
(for feedcrop production); on-farm fossil fuel - both livestock
and feed related; deforestation for pasture and for feedcrop
production; desertification of pasture; livestock processing
and refrigerated transport; in addition to direct production
through enteric fermentation and manure management.(3)
The UN FAO is not a vegetarian organization, but the conclusion
is pretty self-evident: changing to a vegetarian diet is probably
the most effective thing an individual can do to halt climate
change.
In Australia, National Greenhouse Inventory reports
show that livestock are responsible for more greenhouse gas
emissions than industry, residential transport or household
energy use.(4)
Livestock contribute both directly and indirectly to global
warming. Global warming is caused by three main "greenhouse"
gases - carbon dioxide, methane and nitrous oxide, each with
a different greenhouse potency. However, by international convention,
the impact of all gases in measured in "CO2 equivalent" to allow
the overall impact on the environment to be compared.(5)
|
Carbon dioxide:
Animal farming indirectly contributes carbon dioxide
through deforestation for pasture and feedcrop land, and
burning of fossil fuels for feed production, farm and
slaughterhouse operations, cold transportation and refrigeration.(6)
Livestock also directly produce carbon dioxide by respiration.(7)
Methane:
Methane (a greenhouse gas 23 times more effective at
warming the globe than CO2) is produced by farm animal
manure. It is also produced by the enteric fermentation
(belching and flatulence) of cattle, sheep and other ruminants.(8)
Nitrous oxide:
Livestock activities contribute nitrous oxide (a greenhouse
gas 296 times more potent than CO2) mainly through manure
and nitrogen fertilizer application.(9)
|
The trouble with animals
Using animals to produce food for human consumption is extremely
uneconomical, since food animals require large amounts of plant
foods to live and grow. The investment is an extremely poor
one - we get back as little as 5% of what we put in.(10)
In environmental terms, this means that an enormous amount of
resources - fossil fuels, fertilizers, cleared land, all with
their own greenhouse impact - are required for grazing or feedcrops.
Instead, growing plant foods for direct human consumption -
although this has its own environmental impact - would require
much less of everything to feed the same human population.
In terms of global warming, the cataclysmic impact of livestock
- whether it be their digestion, their manure, their respiration,
the crops required for their feed - lies in the sheer number
of them. As a six-billion strong human population around the
globe increasingly demands animal products, the global livestock
population soars.(11) In 2004,
the global livestock population numbered over 22 billion - more
than 3 ½ times the human population of the planet - of which
the overwhelming majority were animals bred primarily for food.
The number grows each year by an average of around 3% - or 550
million animals.(12)
"Livestock are one of the most significant contributors
to today's most serious environmental problems. Urgent action
is required to remedy the situation."
Henning Steinfield, Chief of FAO's Livestock Information
and Policy Branch (13)
"The conclusion is simple: arguably the best way
to reduce global warming in our lifetimes is to reduce or eliminate
our consumption of animal products. Simply by going vegetarian
(or, strictly speaking, vegan), we can eliminate one of the
major sources of emissions of methane, the greenhouse gas responsible
for almost half of the global warming impacting the planet today."
Noam Mohr, Earthsave (14)
"Adopting a vegetarian diet would do more for
the environment than burning less oil and gas."
Alan Calverd, UK Physicist (15)
Find out about Vegetarian Action's 'Great
Green Quiz' campaign - help print & distribute flyers
Read more about food animals and the environment
Notes & References
| 1. |
"The livestock sector is a major player, responsible
for 18 percent of greenhouse gas emissions measured in CO2
equivalent. This is a higher share than transport." (From
Executive Summary)
Steinfeld, H. Gerber, P. Wassenaar, T. Castel, W. Rosales,
M. de Haan, C. Food and Agriculture Organisation of the United
Nations, November 2006. Livestock's long shadow: Environmental
issues and options. (Hereafter abbreviated to 'Livestock's
long shadow'.)
Executive Summary and full report available online at http://www.virtualcentre.org/en/library/key_pub/longshad/A0701E00.htm
(accessed 6/3/2007).
"Livestock" refers to all farmed animals - including cattle,
sheep, poultry and pigs. However, it is clear throughout the
report that food production is the issue: "With increased
prosperity, people are consuming more meat and dairy products
every year. Global meat production is projected to more than
double from 229 million tonnes in 1999/2001 to 465 million
tonnes in 2050, while milk output is set to climb from 580
to 1043 million tonnes." (FAONewsroom - see reference
13)
|
| 2. |
Food & Agriculture Organisation of the United
Nations, 2006. 'Livestock Impacts on the Environment', Spotlight
/ 2006, Agriculture 21 Magazine, http://www.fao.org/ag/magazine/0612sp1.htm,
(accessed 3/6/2007).
|
| 3. |
'Livestock's Long Shadow',
Chapter 1: Introduction, pp.4-20, and Chapter 3, Table 3.12:
Role of Livestock in carbon dioxide, methane and nitrous oxide
emissions, p.113. |
| 4. |
Figures and comparisons for Australian greenhouse
gas emissions are based on two reports from the Australian
Greenhouse Office:
1) Australian Government Department of the Environment and
Water Resources - Australian Greenhouse Office, 2005. National
Greenhouse Gas Inventory 2005: Accounting for the 108% target.
(Abbreviated to NGGI)
2) Australian Government Department of the Environment and
Water Resources - Australian Greenhouse Office, 2005. National
Inventory by Economic Sector 2005. (Abbreviated to NIES)
Summaries and full reports available online - links from Publications
homepage at http://www.greenhouse.gov.au/inventory/publications/index.html
(accessed 3/06/2007). The Australian Greenhouse Office homepage
is at www.greenhouse.gov.au
The Australian Greenhouse Office National Greenhouse
Gas Inventory 2005 shows agriculture responsible for 16% of
national greenhouse emissions for that year (NGGI, Figure
shown on page 1), of which livestock account for 11.1% (NGGI,
Appendix 2 - 2005 Sectoral Emissions, Table 3, p. 17). However,
this figure takes into account only direct contributions through
enteric fermentation (10.5%) and manure management (0.6%).
"Greenhouse gas emissions from livestock are the sum of the
enteric fermentation and manure management subsectors." (NGGI,
p. 11) Thus in comparison with the FAO calculation, the Australian
estimate can be seen to significantly underrepresents livestock's
contribution to greenhouse gases, since it omits to factor
in emissions resulting from factors such as fossil fuels used
in feedcrop production and animal product processing, burning
of savannas for grazing/pasture management and for feedcrop
production, and direct emissions from respiration. In Australia,
'land use change for deforestation' alone contributes a further
9.5% of total net national emissions (NGGI, Table 4, p. 17),
a significant proportion of which would be related to livestock
activities. Despite the underestimation in Australian calculations
livestock's true impact, the National Inventory still reveals
livestock as having a greater impact compared to manufacturing
industries and construction - responsible for 7.8% of total
net national emissions (NGGI, Table 1, page 16), compared
to residential transport - responsible for 8.3% of emissions
(NIES, Figure 12 - 'Allocation of Greenhouse Gas Emissions
by Source, Economic Activity and Greenhouse Gas, Australia,
2005', p. 15) and compared to household energy use - responsible
for 10.4% of emissions (ibid)
|
| 5. |
Australian Government Department of the Environment
and Water Resources - Australian Greenhouse Office, 2005.
National Inventory by Economic Sector 2005, p. 2.
|
| 6. |
Livestock's Long Shadow'
(see Reference 1), Chapter 3 - 'Livestock's role in climate
change and air pollution', p. 112 and Table 3.12 on p. 113. |
| 7. |
"All farm animals produce carbon dioxide
by normal respiration. The amounts emitted by one animal per
year are about 4,000 kg for cattle, 400 kg for sheep and 450
for pigs. This compares with about 300 kg for a human being
and 5,500 kg for a typical passenger car."
Pye, David. 'Why Environmentalists are Not Vegetarian',
New Vegetarian and Natural Health, Summer 2002/03,
pp.38-30, sourced from Carter et al, Agriculture and Pollution,
1999.
|
| 8. |
'Livestock's Long Shadow' (see Reference 1),
Chapter 3 - 'Livestock's role in climate change and air pollution'.,
pp. 112-114.
|
| 9. |
'Livestock's Long Shadow'
(see Reference 1), Chapter 3 - 'Livestock's role in climate
change and air pollution'., p. 114. |
| 10. |
"It takes twenty-one
pounds (9 kg) of protein fed to a calf to produce a single pound
(450 gr) of animal protein for humans. We get back less than
5 percent of what we put in."
Singer, Peter. Animal Liberation, Second Edition, London: Jonathan
Cape, 1990, p.165. |
| 11. |
"Growing populations
and incomes, along with changing food preferences, are rapidly
increasing demand for livestock products, while globalization
is boosting trade in livestock inputs and products. Global production
of meat is projected to more than double from 229 million tonnes
in 1999/01 to 465 million tonnes in 2050, and that of milk to
grow from 580 to 1043 million tonnes."
From 'Global Importance of the Sector', Executive Summary, 'Livestock's
long shadow' |
| 12. |
World Resources Institute
- EarthTrends: the environmental information portal http://earthtrends.wri.org/text/agriculture-food/variables.html
(accessed 4/6/07). Figures compiled from timemaps for populations
of buffalo, camels, cattle, chicken, duck, equine (horses, asses
and mules), goats, sheep, swine and turkey.
Total aggregate world population for 2004: 22,113,446,000
Average percentage growth per year calculated over period 1998-2004
Figure for 'Animals bred primarily for food' calculated by excluding
buffalo, camels, equine and sheep from world total. (Conservative
figure, as sheep are used for food.) Total livestock population
for 2004 excluding these categories: 20,755,352,000. % of total
livestock population for same year: 94%. |
| 13. |
Food and Agriculture
Organization of the United Nations, FAO Newsroom, November,
2006. 'Livestock a major threat to environment - remedies urgently
needed'. http://www.fao.org./newsroom/en/news/2006/1000448/index.html
(accessed 3/6/07). |
| 14. |
Mohr, Noam. 'A New Global
Warming Strategy - How environmentalists are overlooking vegetarianism
as an effective tool against climate change in our lifetimes'.
An EarthSave International Report, August 2005. Available online
at http://www.earthsave.org/news/earthsave_global_warming_report.pdf
(accessed 3/06/07). |
| 15. |
Calverd, A. 'A radical
approach to Kyoto', Physics World, July 2005. |
Page updated: 5 June 2007
Whichever way you look, the future
is vegetarian...
|
