Eat a steak, warm the planet

A kilogram of beef causes more greenhouse-gas and other pollution than driving for three hours while leaving all the lights on back home, according to a Japanese study.

A team led by Akifumi Ogino of the National Institute of Livestock and Grassland Science in Tsukuba, calculated the environmental cost of raising cattle through conventional farming, slaughtering the animal and distributing the meat, New Scientist reports in Saturday's issue.

Producing a kilogram of beef causes the equivalent of 36.4 kilograms in carbon dioxide, the principal greenhouse gas, Ogino found.

Most of these greenhouse-gas emissions take the form of methane, released from the cow's digestive system.

That one kilogram of beef also requires energy equivalent to lighting a 100-watt bulb for nearly 20 days. The energy is needed to produce and transport the animals' feed.

A Swedish study in 2003 suggested that organic beef emits 40 per cent less greenhouse gases and consumes 85 per cent less energy because the animal is raised on grass rather than concentrated feed.

The study appears in full in a specialist publication, Animal Science Journal.
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