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Modern farming uses huge amounts of
energy to grow, process
and transport foods. Livestock farming, particularly of cattle,
is
responsible for a significant fraction of all GHG. New research
suggests
that one kilogram of beef adds 36 kilograms of CO2 and other climate
changing
pollutants to the atmosphere. [1]
Global demand for meat has multiplied in recent years, encouraged by
growing
affluence and nourished by the proliferation of huge, confined animal
feeding
operations.
These assembly-line meat factories consume enormous amounts of energy,
pollute
water supplies, generate significant greenhouse gases and require
ever-increasing amounts of corn, soy and other grains, a dependency
that has
led to the destruction of vast swaths of the world's tropical rain
forests. [2]
Economic growth is usually accompanied by an increasing demand for
meat, as
more people can afford it (Eickhout et al., 2006). In addition,
populations are
still increasing in developing countries which will fuel an increased
demand
for food even in the absence of dietary changes. The UN predicts that
the world
population will continue to increase from the present about 6.5 billion
and
stabilise at over 9 billion (UN, 2004). [3]
The world's total meat supply was 71 million tons in 1961. In 2007, it
was
estimated to be 284 million tons. Per capita consumption has more than
doubled
over that period.
(In the developing world, it rose
twice as fast, doubling in the last
20
years.) World meat consumption is expected to double again by 2050,
which one
expert, Henning Steinfeld of the United Nations, says is resulting in a
"relentless growth in livestock production."
Similarly, a study last year by the National Institute of Livestock and
Grassland Science in Japan
estimated that 2.2 pounds of beef is responsible for the equivalent
amount of
carbon dioxide emitted by the average European car every 155 miles, and
burns
enough energy to light a 100-watt bulb for nearly 20 days. [4]
Growing demand for meat may induce further changes in land use (e.g.,
from
forestland to grassland), often increasing CO2 emissions, and increased
demand
for animal feeds (e.g., cereals). Larger herds of beef cattle will
cause
increased emissions of CH4 and N2O, although use of intensive systems
(with
lower emissions per unit product) is expected to increase faster than
growth in
grazing-based systems. This may attenuate the expected rise in GHG
emissions.
Intensive production of beef, poultry, and pork is leading to increases
in
manure with consequent increases in GHG emissions. This is particularly
true in
the developing regions of South and East Asia,
and Latin America, as
well as in North America.
(IPCC WGIII Ch.8, 2007) [5]
Though some 800 million people on the planet now suffer from hunger or
malnutrition, the majority of corn and soy grown in the world feeds
cattle,
pigs and chickens.
This despite the inherent inefficiencies: about two to five times more
grain is
required to produce the same amount of calories through livestock as
through
direct grain consumption, according to Rosamond Naylor, an Associate
Professor
of Economics at Stanford
University.
It is as much as 10 times more in the case of grain-fed beef in the US. [6]
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