How big is your carbon hoofprint?

Cows: Cows and climate change

Anyone concerned about climate change would do well to limit their beef intake, argues Duncan Clark

Green beans from Kenya, apples from New Zealand … we hear a lot about the climate costs of our fruit and veg. By comparison, meat tends to get off rather lightly – strange when you consider that most has a larger carbon footprint than its veggie alternative.

But some meats are worse than others, with beef being perhaps the biggest offender. Producing a single kilogram of the stuff can result in a whopping 36.4kg of CO2 – the same as driving a gas-guzzling SUV for 50 miles.

Feeding climate change

Many of beef’s emissions come from growing cattle feed. It can take 10kg of beans or grains to produce just one kilogram of beef. Growing all this feed requires a great deal of energy – for making fertiliser and pesticides, powering farm vehicles and transporting the final crop to market.

To make matters worse, the demand for land to grow animal feed and graze cattle is one of the biggest factors driving deforestation of rainforests. With this destruction factored in, the UN has calculated that livestock accounts for around a fifth of the total human impact on the climate – more than every car, lorry, ship and plane combined.

Belching methane

Beef: The carbon footprint of beef

Another big part of beef’s carbon footprint is its methane emissions. Cows are ruminant animals, which means their digestive system creates a large amount of methane – a highly potent greenhouse gas – as a by-product.

One cow emits more than 100kg of methane annually. That’s equivalent to more than 2 tonnes of CO2, or the beast in question taking a yearly return flight from Britain to the US.

Scientists have developed pills to reduce the flatulence of cattle, but they haven’t yet been rolled out widely and they only reduce, rather than stop, the emissions. Another approach that’s been mooted is keeping the cows in sealed sheds and extracting the methane from the air. But even if this works, it raises obvious animal-welfare concerns.

Greener meats

So is it possible to get a pound of flesh without a tonne of guilt? In the case of beef perhaps not, although if it’s grass-fed it is a bit greener, since it reduces the demand for feed. But even the most overtly “ethical” beef available – organic, free-range, grass-fed, locally sourced – produces large quantities of methane.