If you're the kind of person who would make a lifestyle change based on its impact on the climate, you're probably already aware that your food choices impact the molecular balance of the atmosphere in ways pertinent to life as we know it. By some estimates, half of human greenhouse gas (GHG) emissions are released by the production, transport, preparation, and waste of food. Thanks to population growth and economic development, that portion is growing.
This reality has spawned a foodie tribe known as the climatarians, members of which, according to The New York Times, adhere to a "diet whose primary goal is to reverse climate change." You might think of climatarians as allies to the locavores, fellow do-gooders trying to save the world by eating carefully. But their agendas are not always aligned. It turns out that the distance food travels makes less of a difference to the carbon footprint than how that food was produced.
Many studies indicate concentrated animal feeding operations, or CAFOs, are more efficient than raising grass-fed animals because the operations benefit from the economics of scale. They are more efficient, the animals grow faster, and are ready for slaughter sooner, so they end up producing less methane over the course of their lives. The emission of methane, a much more potent greenhouse gas than carbon dioxide, is a big reason animal products are shunned altogether by many climatarians. Others will try to keep their meat but eat it as efficiently as possible. While the average omnivorous locavore may balk at the idea of a fast food burger, a climatarian might pull into the drive-thru, turn off his engine, and marvel at the efficiencies of the modern food system while awaiting his turn.
To determine the most anti-climatarian meal ever, I used an online tool called the Food Carbon Emissions Calculator, created by a company called CleanMetrics. Top of the list is red meat, with lamb being the worst — nearly 12 kilograms of atmospheric carbon is released per pound of meat. So while lamb is certainly on the menu, we need to make sure it's the right lamb. Most of the lamb consumed in the U.S. is from New Zealand, from where it must be shipped, frozen. Shipping something from around the world that grows perfectly well in the U.S. seems about right. And then we don't have to worry about local, pasture-raised lamb, because that, likely, won't be bad enough.
We need to select a cut of lamb that requires the most cooking, releasing as much carbon dioxide as possible. We want to cook it for hours and serve it with out-of-season sides and creamy desserts.
The main course will be braised lamb shanks, aka osso bucco. Shank is the only part of a lamb's body that could benefit under extended cooking, thanks to its being the toughest (and arguably tastiest) part of the lamb — so tough it needs to be cooked for hours to render it chewable. In order to waste as much energy as possible, we will braise the shanks in a big oven rather than a more efficient crock pot.
While a head of California lettuce shipped across the country would only set the climate back about 0.2 kilograms of atmospheric carbon, if we can import the same thing out of season — raised in a greenhouse in Sweden, for example — then we are talking four-and-a-half kilos of carbon dioxide. That's nearly twice the carbon impact of Norwegian lobster, at two and a half kilograms.
While a vegan diet is generally going to be better for the climate than what we would enjoy at the Brazilian barbecue, the Swedish lettuce example shows that blind allegiance to vegetables could cause you to do more damage to the climate with that salad than you would have done with a lobster roll. I, for one, would lean toward the lower emission lobster.
Altogether, a climate denier's Happy Meal of braised osso bucco with Swedish lettuce and artisan Wisconsin cheese plate could generate about 21 kilograms of carbon dioxide. A meal of lentils, vegetables, and rice, on the other hand, comes in at about half a kilogram. We could throw in a bottle of wine and still be under a kilo. That, and the occasional Norwegian lobster, would keep you well-fed and guilt-free.
But the most important take-home from this exercise is that if you put a little thought into where your food comes from, you don't need to blindly follow any one ideology. With a little brainpower, you can assess for yourself how good or bad food is, for yourself and the world.