Cows pollute more than cars…who woulda thought…phew!
Killer cow emissions
Livestock are a leading source of greenhouse gases. Why isn't anyone raising a stink?
October 15, 2007
It's a silent but deadly source of greenhouse gases that contributes more to global warming than the entire world transportation sector, yet politicians almost never discuss it, and environmental lobbyists and other green activist groups seem unaware of its existence.
That may be because it's tough to take cow flatulence seriously. But livestock emissions are no joke.
Most of the national debate about global warming centers on carbon dioxide, the world's most abundant greenhouse gas, and its major sources -- fossil fuels. Seldom mentioned is that cows and other ruminants, such as sheep and goats, are walking gas factories that take in fodder and put out methane and nitrous oxide, two greenhouse gases that are far more efficient at trapping heat than carbon dioxide. Methane, with 21 times the warming potential of CO2, comes from both ends of a cow, but mostly the front. Frat boys have nothing on bovines, as it's estimated that a single cow can belch out anywhere from 25 to 130 gallons of methane a day.
It isn't just the gas they pass that makes livestock troublesome. A report from the United Nations Food and Agriculture Organization identified livestock as one of the two or three top contributors to the world's most serious environmental problems, including water pollution and species loss. In terms of climate change, livestock are a threat not only because of the gases coming from their stomachs and manure but because of deforestation, as land is cleared to make way for pastures, and the amount of energy needed to produce the crops that feed the animals.
All told, livestock are responsible for 18% of greenhouse-gas emissions worldwide, according to the U.N. -- more than all the planes, trains and automobiles on the planet. And it's going to get a lot worse. As living standards rise in the developing world, so does its fondness for meat and dairy. Annual per-capita meat consumption in developing countries doubled from 31 pounds in 1980 to 62 pounds in 2002, according to the Food and Agriculture Organization, which expects global meat production to more than double by 2050. That means the environmental damage of ranching would have to be cut in half just to keep emissions at their current, dangerous level.
