Can Vegetarianism Save the World? Nitty-gritty

By Jess McNally

What is the impact of a person becoming a vegetarian on global warming?

At this point you may be thinking: “All right, I could eat a little less meat, but will it really make such a big difference?” I hope to add some meat to that claim here.

Livestock, does it really matter in the scheme of all greenhouse gas emissions?

In short, yes! Depending how the figure is calculated, livestock account for anywhere between 18 and 51 percent of global greenhouse gas (GHG) emissions measured in CO2 equivalent.  This number is reported in CO2 equivalent because many of the gases released by agriculture, such as methane, have 23 times the global warming potential (GWP) of CO2. Nitrous oxide, of which livestock is responsible for 65 percent of anthropogenic output, has 296 times the GWP of CO2. Raising farm animals is a huge part of our climate change problem, and cutting back on animal products is one of the biggest, most immediate things we all can do to help.

Changes in land use due to livestock are also a significant contributor to our global carbon footprint. We impact more land with livestock grazing than with any other use, including crops, roads and cities. According to a report by the Food and Agriculture Organization, livestock are the single largest anthropogenic user of land. The total area occupied by grazing is equivalent to 26 percent of the ice-free terrestrial surface of the planet—a full quarter of our livable Earth! Beyond the fact that much of this land was once forest before being converted to pasture, over 20 percent of the pastureland in the world are degraded to some extent by overgrazing, compaction and erosion.  All of these processes release carbon to the atmosphere, and reduce the potential for restoring this carbon in the future.

Why does meat produce more emissions than a vegetarian diet?

The simplest way to think about why meat produces more emissions is in terms of the efficiency of converting grain to edible meat. Or even more, plant protein to animal protein.  The U.S. livestock population consumes more than seven times as much grain as is consumed directly by the entire American population (Pimentel 2003). All the fertilizer, tractor fumes, transportation, ground tilling, you name it, that go into producing a pound of grain are literally multiplied by 4.5 to produce a pound of chicken breasts, or by 20 to produce a pound of ground beef.  It takes 4.5 pounds of grain to make 1 pound of chicken meat and 7.3 pounds of grain to produce 1 pound of pork. Approximately 700 calories worth of feed are needed to produce just one 100-calorie piece of beef.

 Up till now I thought of vegans as a bunch of nuts. (pun intended) but when I heard on NPR a piece similar to the one above, it spun my head around.  So last night a friend and I ate dinner at the Munch vegan restaurant in Oak Park.  The food was delicious