Big feet

Food miles, carbon footprints, big confusion

By Caroline Cummins

February 26, 2008

This week’s issue of the New Yorker features an article by Michael Specter titled “Big Foot.” No, it’s not about Sasquatch. It’s about food miles, and carbon footprints, and trying to save the planet in a seemingly simple way that’s actually bogglingly complicated.

“Possessing an excessive carbon footprint is rapidly becoming the modern equivalent of wearing a scarlet letter,” Specter writes. “Because neither the goals nor acceptable emissions limits are clear, however, morality is often mistaken for science.”

Specter profiles British supermarket chains Tesco and Marks & Spencer, which are trying to reduce their carbon footprint — in other words, to reduce the amount of carbon dioxide and other greenhouse gases they produce in the course of their daily business — by cutting energy use, selling fewer products transported by air, recycling, and putting “carbon labels” on products informing customers how carbon-clean (or otherwise) an item might be. But as Specter points out, calculating an accurate carbon label is very tricky:

The calculations required to assess the full environmental impact of how we live can be dazzlingly complex. To sum them up on a label will not be easy. Should the carbon label on a jar of peanut butter include the emissions caused by the fertilizer, calcium, and potassium applied to the original crop of peanuts? What about the energy used to boil the peanuts once they have been harvested, or to mold the jar and print the labels?

Specter goes on to say that the production and consumption of food is, well, small potatoes compared to worldwide energy use for travel, heating, cooling, and manufacturing. But the concept of food miles — how far a food item travels from production to consumption — is an easy shorthand for thinking about how much we waste. Which is exactly why Specter challenges it, quoting British researcher Adrian Williams:

“The idea that a product travels a certain distance and is therefore worse than one you raised nearby — well, it’s just idiotic,” [Williams] said. “It doesn’t take into consideration the land use, the type of transportation, the weather, or even the season.”

What Specter leaves out, of course, are questions of freshness and taste — two very good reasons to eat locally and seasonally. (He also repeats, credulously, the wobbly conclusions of last year’s much-reported study on New Zealand lamb.) But the article is worth reading for its broad look at global warming and various corporate efforts to do the right thing. Remember acid rain? There’s a quick recap of that story here. Interested in carbon offsets? Yup, that’s here, too. Want the latest on rainforest destruction? Specter’s your boy.

He also quotes Jimmy Carter’s famous speech from 1977, in which the American president — dressed in one of his many cardigans, to emphasize turning down the thermostat — told the nation that, like it or not, they would have to start conserving resources and stop being so darn wasteful: “We must not be selfish or timid if we hope to have a decent world for our children and grandchildren.”