lundi 27 avril 2009

Kyoto Action Report : Here Come the Cows


 
Pull Over Cars, Here Come the Cows
 
Eating for a Cooler Planet, Part 2

From its start, Kyoto Action has claimed that excessive meat eating is one of the four primary causes driving global warming. In December 2008, the UN Food and Agriculture Organization (UN FAO) issued a major study on the impact of massive herds and livestock have on global warming and environmental degradation. In the study, entitled "Livestock's Long Shadow", scientists and agricultural experts analyze greenhouse gas emissions over the full cycle of meat production, from planting feed crops and raising animals to packaging meat products and transporting them to local markets.

The study's stunning result shows that the combined emissions from all phases of meat production are now greater than for all transportation worldwide including cars, trucks, trains, ships, and airplanes! Livestock accounts for 18 percent of global emissions, while transportation is responsible for 17 percent.

 

A rapidly changing world, rapidly changing diets

The greatest change in our world is population growth: 6.5 billion humans and steadily increasing. These last two decades have seen another change that dangerously compounds the problem of population explosion: an economic growth worldwide, powered by burning more fossil fuel, particularly in the most populous countries of India and China. With increasing incomes has come the trend of people in poorer countries to abandon their traditional vegetable and grain-based diets for a Western meat-based one. Together the populations of China, India, Brazil, and other countries now consume 33 percent more red meat than a decade ago.

Over that same period, Western countries did not stand still in this 'meat race'. Today the average American daily consumes approximately two pounds (one kilogram) of animal food (meat, fish, dairy, eggs, and cheese)(Source: US Department of Agriculture). The world is in a veritable meat feeding-frenzy.

To satisfy this demand for meat, the number of livestock worldwide has exploded. Between 1961 and 2002, livestock biomass jumped 270 million tonnes  (tonne = 1000 kg, or 2200 lb), representing a 63 percent increase (Source: UN FAO). By 2002, there was an average of one cow for every four people on the planet. This livestock explosion brings an unprecedented aftershock of environmental devastation that includes global warming, deforestation, water pollution, desertification, and disease.

 

Sizing up the livestock problem

The numbers below help to understand the scope of the environmental problems caused by livestock.

19, 000, 000, 000 was the approximate head count in 2002 of all livestock animals. These animals are the primary cause of land degradation, deforestation, water and air pollution. Also, such animal densities are breeding grounds for the propagation of epidemics such as Bird Flu.

70 percent of the world's agricultural land is devoted to grazing herds and raising feed crops to sustain them. Meanwhile in 2007 and 2008, 115 million more people entered the dark shadow of daily hunger, pushing the total worldwide to nearly one billion people (more than the combined populations of the U.S., Canada, and the European Union.)

50 percent of the world's maize crop is used to feed animals, not humans.

70 percent of the deforested lands that were once rainforest are used for grazing and growing feed for cattle.

30 percent of the land surface occupied by livestock was previously wildlife habitat; intensive farming has greatly endangered biodiversity.

71 percent of the world's grasslands are threatened with desertification as a result of overgrazing, salinization, alkalinization, and other processes due to herds.

50 percent of antibiotics produced in the United States are used to artificially enhance animal weight gain and to prevent diseases caused by overcrowding and the effects of force-feeding cattle corn and grain instead of their natural food, grasses and herbs. This practice has caused antibiotic-resistant bacteria in humans.

55 percent of the soil erosion and sediment pollution in the U.S. is caused by herds.

37 percent of pesticide use in the U.S. is applied to livestock feed crops.

Livestock causes one-third of the nitrogen and phosphorous contamination in fresh water resources.

 

Massive herds gassing up global warming

Both in their natural bodily functions, and in the industrial processes involved, livestock contributes significantly to the gases that cause global warming and air pollution: carbon dioxide, methane, nitrous oxide, and ammonia.

Carbon dioxide (CO2)—The natural respiration of livestock (inhaling oxygen and exhaling carbon dioxide) adds significant quantities of this heat-trapping gas to the atmosphere. But it doesn't end there. To be accurate the entire cycle of meat production must be looked at. First, consider the fossil fuel used in transporting feed crops. For example, soybeans are trucked from fields in Brazil and shipped across the ocean to feed livestock in the U.S. and Europe. Then consider that the feed crops themselves need fossil fuel-powered machinery to plant and harvest. The feed crops also need massive quantities of mineral fertilizer in order to grow, and this fertilizer is produced, again, by burning fossil fuel. Finally, note that the land for the feed crops has been reclaimed from what was once forest (frequently rainforest) whose trees metabolized carbon dioxide out of the atmosphere, and are now no longer there.

Looking at the other end of the meat production chain, the livestock is transported using fossil fuel to slaughterhouses and meat packing factories, which are powered by fossil fuels. The meat products are distributed to markets using refrigerated transport and are stored in giant refrigerated areas, powered yet again by fossil fuel. It is estimated that this entire livestock cycle is responsible for generating and emitting nearly 20 million tonnes of carbon dioxide annually. (tonne = 1000 kg, or 2200 lb)

Methane (CH4)—Sometimes referred to as 'swamp gas', methane is another major emission from livestock and the meat production process. Methane, which traps 23 times more heat than carbon dioxide, is more damaging in terms of global warming. Cows and other ruminant animals produce methane during digestion (by fermentation) and expel this gas from 'both ends' almost continuously. Due to the sheer numbers of cattle, this gas has become a major contributor to global warming. In addition, when cows are force-fed grain instead of their natural food—grasses—they produce more methane in their digestive systems (and suffer indigestion, which is treated with antibiotics).

More methane is released from the fertilizers that are applied to feed crops, and from decaying livestock manure. As a result of this cycle, livestock are responsible for 37 percent of all human-related methane production worldwide.

Nitrous oxide (N2O)—This gas is formed from car exhaust and sunlight and is the main component of smog found around urban centers. Today, nearly 65 percent of human-induced nitrous oxide comes not from car exhaust but from decaying livestock manure, mostly from cows.

Nitrous oxide is one of the most potent heat-trapping gases known--296 times that of carbon dioxide. It also destroys the atmosphere's ozone layer that protects us from ultraviolet solar radiation. Atmospheric scientists estimate that if the amount of nitrous oxide were to double, it would destroy ten percent of the ozone layer, causing a 20 percent increase in ultraviolet radiation reaching the Earth's surface.

According to the World Health Organization, current levels of ultraviolet radiation are already responsible for more human skin cancer and eye cataracts.

"Between 2 and 3 million non-melanoma skin cancers and at least 132,000 malignant melanomas occur globally each year. There has been a significant increase in the incidence of skin cancers since the 1970s… Sun exposure may also be responsible for more than 2 million cases of blindness due to cataracts worldwide."

Ammonia (NH3)—This pungent gas is an official air pollutant. Experts estimate that the annual release of ammonia has steadily increased since the end of the 19th century from 18.8 million tonnes annually to 56.7 million tonnes in 1991.

Besides damaging the human respiratory system, ammonia in the atmosphere forms acid rain that has already destroyed entire regions of forests and has turned many once-pristine lakes and streams into biological dead zones.

Livestock manure and urine are responsible for nearly two-thirds (64 percent) of the world's human-induced ammonia emissions.

 

Livestock carbon footprints

The chart below shows the carbon footprints from different animal products and tomatoes, as a reference point. The carbon footprint values indicate the unit weight (lbs or kg) of equivalent carbon dioxide produced for the same unit weight (lbs or kg) of each food.

Carbon footprint of meats

(Source: Lantmannen, Sweden)

It's easy to see that the clear winner for the environment is chicken with a footprint of only 1.8, beating hothouse tomatoes by a full point! The worst environmental choice is beef with a footprint of 20. The chart offers several other surprises. For one, if you thought eating cheese or shrimp was better for the environment, think again; they have some of the largest footprints. Meanwhile, pork(!) is a far better choice with less than half the footprint of cheese or shrimp.

 

What you can do to help

In the words of Dr. Pachauri, head of the U.N. Intergovernmental Panel for Climate Change, "the most attractive" near-term solution is for everyone to simply "reduce meat consumption", a change, he says, that would have more impact than switching to a hybrid-energy car.

You can also modify your diet to eat more of the animal products with the lowest carbon footprints and less of those products with the highest.

In light of the new UN Food and Agriculture Organization study, Kyoto Action recommends limiting daily consumption of animal products to between 11-16 oz or 300-500 grams, which is less than half the average American consumption. These quantities, however, are still above those in the Okinawa and Cretois (aka, Mediterranean) diets for optimal health.

 Dennis Shibut

(Creator of the Kyoto Action website, MS Physics, member of the Union of Concerned Scientists, former researcher for NASA and US Coast & Geodetic Survey)

Special thanks to Kath Massam and Mary Podevin for their assistance in preparing this report.

Please forward this message to all those on your personal mailing list who would be interested in its content. And thank you in advance for doing so.

To find out what other personal actions you can take to change the course of global warming and climate change, visit our Website at www.kyotoaction.com .

 

1 commentaire:

Anonyme a dit…

you said there was one cow for every four human beings. Do you not mean the other way around? My readings shows that, certainly for livestock in general including poultry, there are at least four livestock animals on the planet for every person.

Eleanor Boyle, PhD
Vancouver, Canada