A related issue when it comes to comparing the ecological impact of the food is methane–which has 72 times the global warming potential as carbon. Last year was a big year for methane research. Scientists discovered that U.S. methane output is 50 percent more than the EPA was estimating and 70 percent more than the figure cited by th European Environmental Agency's Emission Database for Global Atmospheric Research (EDGAR). Especially revealing was the fact that livestock related emissions were twice the current estimates, accounting for up to 33 percent of global methane emissions. Cows burp and defecate, methane escapes, it harms the environment. This claim holds true for factory farmed and pastured animals.
Given these kinds of figures, in addition to the urgency with which environmentalists rightfully urge humans to adjust their behavior to prevent planetary implosion, it strikes me as a little ridiculous that we're actually having serious arguments over whether or not veganism is a good move for the environment. Of course it is.
Let's close that case and start talking about why the eco-foodies who wring their hands so earnestly about ecological destruction are not taking the obvious and in many ways the most accessible step of exclusively eating plants.