The Island of Doubt

Among the most common questions that follow my presentations of Al Gore's climate change slide show is "What about vegetarianism?" I usually respond that eating less meat will probably be a consequence of climate change, due to the enormous water and energy costs associated with raising livestock, rather than a significant mitigation strategy. But I'm going to reconsider the situation, in the light of this paper in Animal Science Journal.

"Evaluating environmental impacts of the Japanese beef cow-calf system by the life cycle assessment method" (doi: 10.1111/j.1740-0929.2007.00457.x) takes a look at the greenhouse gas emissions, among other nasty side-effects, associated with beef. It's not pretty.

The authors, from the National Institute of Livestock and Grassland Science in Tsukuba, and Kyoto University, did a thorough job calculating all of the energy inputs:

Lighting the cattle barn, feed preparation and carrying manure out of the barn were taken into account as the work associated with animal management, and environmental loads were calculated from the quantities of fuel and electricity consumed in the work.

At the end of the day, when the abattoir has been tidied up,

... the total contributions of one beef calf throughout its life cycle to global warming, acidification, eutrophication and energy consumption were 4550 kg of CO2 equivalents, 40.1 kg of SO2 equivalents, 7.0 kg of phosphate (PO4) equivalents and 16.1 GJ, respectively.

What does all that mean in terms that you can sell to a news editor? Fortunately, Daniele Fanelli at New Scientist, tells us:

In other words, a kilogram of beef is responsible for the equivalent of the amount of CO2 emitted by the average European car every 250 kilometres, and burns enough energy to light a 100-watt bulb for nearly 20 days.

The calculations, which are based on standard industrial methods of meat production in Japan, did not include the impact of managing farm infrastructure and transporting the meat, so the total environmental load is higher than the study suggests.

Before anyone jumps to some lifestyle conclusion, this does not mean that we should all become vegetarians for fear of spending the rest of our environmentally responsible lives as hypocrites. There are sources of animal protein that do not entail fossil-fuel use and monstrous amounts of enteric methane production. For example, when I lived in Canada's Northwest Territories, my ecological footprint was probably much lower than it ever will be even though I at plenty of animals. The difference was most of my red meat was caribou, which as a lichen-munching wild creature contributed hardly at all to global warming. And my fish was taken from nearby lakes with a minimum amount of effort.

We can't all live like that. I can't even live like that anymore. But the point is a carnivorous diet is not necessarily a climate-changing evil. It just means that reducing beef consumption is probably going to be a necessary part of mitigating climate change.

Of course, if we don't slow the global warming, we'll all be denied beef thanks the drought conditions that will almost certainly dominate cattle-ranching territories the world over. So either way...