Saturday, May 3, 2008

How Food Choices Affect the Environment

A couple of the good articles from last week's New York Times Magazine. Go to nytimes.com to read their Green issue.

THE HIGH PRICE OF BEEF: Late in February, the governors of Maine, Rhode Island, Washington, Maryland and other states received letters from Lindsay Rajt of People for the Ethical Treatment of Animals, asking them to encourage the citizens of their states to become vegetarians. The governors of those states have been fighting for tighter vehicle-emissions standards as a way to combat climate change. That made them a target for the folks at PETA, who argue that the climate impact of the car pales in comparison to that of the cow. A 2006 report by the United Nations Food and Agriculture Organization found that livestock production accounts for 18 percent of the world’s greenhouse-gas emissions — more than all forms of transportation combined. Meat’s supersize impact comes from fuel- and fertilizer-intensive agricultural methods of growing feed, all the power needed to run slaughterhouses and meat-processing plants and the potent greenhouse gases produced by decomposing manure. Pork, lamb and poultry all have their impacts, but beef is undoubtedly the Hummer of the dinner plate. Sixty percent of the deforestation in the Amazon River basin between 2000 and 2005 can be attributed to cattle ranching; much of the remainder was cleared to raise corn and soy for feed. And cows, once fed, burp — a lot. Each day, a single cow can burp as much as 130 gallons of methane, a greenhouse gas that traps more than 20 times more heat per ton than carbon dioxide. Trimming the amount of meat Americans eat would not only help the planet — a mere 20 percent reduction is the equivalent of switching from a Camry to a Prius — but would also be likely to reduce obesity, cancer and heart disease. Until recently, it was only animal rights groups like PETA that were willing to ask Americans to forgo the pleasures of the flesh. That changed in January, when Rajendra Pachauri, the head of the Intergovernmental Panel on Climate Change (and a vegetarian), uttered four little words: “Please eat less meat.” He continued: “This is something that the I.P.C.C. was afraid to say earlier, but now we have said it.” DASHKA SLATER

IS LOCAL ALWAYS BETTER?: From start to finish — from planting seeds to disposing scraps — the food sector accounts for roughly 25 percent of an American’s ecological footprint, according to Susan Burns, a managing director at the Global Footprint Network in Oakland, Calif. “Choices about what to eat have about the same impact, environmentally, as choices about how to drive or transport ourselves,” she says. The average supermarket product travels 1,500 miles to reach the shelf, but Burns concedes that, from a carbon perspective, it can be confusing being green. There’s no one accurate carbon footprint calculator for foods, yet. “To give specific numbers between an apple trucked from Washington State to Massachusetts and a papaya shipped to the grocery store,” Burns says, “you’d have to know everything from the fuel efficiency of the truck to the kind of fertilizer that was used, to the kind of ship the papaya was shipped on.” It is the locavore’s dilemma that organic bananas delivered by a fuel-efficient boat may be responsible for less energy use than highly fertilized, nonorganic potatoes trucked from a hundred miles away. Even locally grown, organic greenhouse tomatoes can consume 20 percent more resources than a tomato from a far-off warm climate, because of all the energy needed to run the greenhouse. Various organizations like the British grocery chain Tesco and the Global Footprint Network itself are trying to design accurate calculators both for carbon outputs and for general ecological impact. But not having them is no reason not to act. Burns recommends the following steps. First, break the packaging habit: “It’s not uncommon for food packaging to use more energy in production than the food it contains,” she says. Next, make it a goal to eat foods that are at once organic, local, seasonal and low on the food chain. Local keeps down the transportation miles. Organic eliminates the high energy costs of pesticides and fertilizers. Seasonal foods do not need greenhouses or long periods of refrigeration. And she notes that the food chain matters, carbon-wise: the CO2 impact of a pound of beef can be 250 times as great as that of a pound of carrots. (Of course, even the most sustainably raised legume racks up carbon points in an inefficient refrigerator.) Lastly, some of the most troublesome aspects of the food cycle occur in disposal. Rotting food is itself an ecological concern, because methane, a byproduct and a greenhouse gas, has an enormous impact on global warming. “Compost and advocate for compost,” she says.