October 23, 2009

Eating Our Way to 350

“The bottom line is that innovations in agriculture provide the best opportunity to remove carbon from the atmosphere. We cannot reach 350 ppm without changing the way we grow our food and use our land.”
– Worldwatch Institute

350 Inspired by International Day of Climate Action, we’ve seen an increased effort to draw people’s attention to the number 350, which leading scientists say is the safe upper limit for carbon dioxide — measured in “parts per million” — in our atmosphere. Although we’ve already exceeded 350 ppm, it is said to be “the number humanity needs to get back to as soon as possible to avoid runaway climate change.”

What does this have to do with our food choices? As it turns out, quite a lot. The industrial food system is commonly said to account for around one third of human-caused greenhouse gas emissions. (Some newly released data suggests it might be more, but we’ll get to that.) The good news is there’s a great deal you can do to reduce your impact.

1) Learn about it, even when it’s overwhelming
If you’re looking for an in-depth primer on food and climate change, the Worldwatch Institute, Anna Lappe’s Take a Bite out of Climate Change site and her fact sheet on Sustainable Table, as well as the official site of the upcoming United Nations Climate Change Conference are some great places to start.

2) Choose organic and sustainably raised food
If everyone converted 10% of their diet to organic, we could capture an addition 6.5 billion pounds of carbon in the soil — the equivalent of taking two million cars off the road each year.

Synthetic nitrogen fertilizer requires massive amounts of energy to produce. For that reason and others, organic farming systems use just 63% of the energy required by conventional farming systems. Synthetic fertilizer is also often overused, leading to runoff and excess nitrous oxide (a harmful and potent greenhouse gas) that ends up in air.

Organic farmers work to build up organic matter in the soil, allowing it to act as a temporary carbon sink, sequestering excess carbon that would otherwise stay in the atmosphere and add to climate change. 

Related Video Can Organics Stop Climate Change?
An interview with Tim LaSalle of the Rodale Institute

cow sign3) Eat less meat and dairy, especially if it’s industrially raised
Livestock production accounts for a significant portion of the world’s total greenhouse emissions; no matter how you slice it, the production of meat and other animal products causes more emissions than the entire transportation sector.

In one brand new report, the Worldwatch Institute claims that livestock actually accounts for as much as 51% of the man-made greenhouse gases on the planet. This is a significant increase over the data reported in an often-cited cited 2006 report, Livestock’s Long Shadow from the United Nations Food and Agriculture Organization.

Animals produce methane, which has over 20 times the global warming effect of carbon dioxide. Industrial-scale storage of animal waste is also a huge factor; when it’s stored in waste lagoons the product is even more methane.

Then there’s the food chain factor; a great deal of energy and resources (and subsequent emissions) go into raising crops for animal feed; it is much more efficient when plant crops go directly to feed people. To make matters worse, the more meat we eat, the more acres of (carbon absorbing) forest are destroyed; in recent decades, millions of acres of forest have been cleared to make way for industrial agriculture, especially soybeans for animal feed.

4) Hone your locavore skills
Despite all the attention paid to “food miles,” emissions from food transport are not the biggest culprit behind the sector’s impact on climate change. That said, our food travels an average of 1,500 to 2,500 miles to get to us; that’s 25 percent farther than it did two decades ago. Not all food transport can be eliminated, but shortening the chain (a great deal of our food travels to multiple countries to be processed) could make a palpable difference. For many of us, it is also one of the easier changes to make.

compost_bin5) Befriend your compost bin
4% of global greenhouse gas emissions comes from waste, including food waste; a full 27% of the food available for consumption gets wasted. Food waste that ends up in landfills emits methane. When it gets properly composted, on the other hand, it can return to the soil (see #2) and help boost its power to retain carbon.

About CUESA

CUESA (Center for Urban Education about Sustainable Agriculture) is dedicated to cultivating a sustainable food system through the operation of the Ferry Plaza Farmers Market and its educational programs. Learn More »