A recent report find that, worldwide, livestock production releases more carbon (or carbon-equivalence) than transportation. Sustainablog has more on this. One thing I’d like to note–because nitrogen fertilizers are major contributors (nitrous oxide has 256 times the global warming power as carbon dioxide), this is yet another good reason to support organic agriculture. In fact, it suggests the possibility that eating organic food that was grown on the other side of the world might have less global warming impact than conventional food grown in your hometown. Now, I didn’t run any numbers on this, so it’s pretty speculative, but given the earlier discussion on local vs. imported food, it the climate impact of distance (for food) seems not to be nearly as great as I had previously thought.