it needs to reduce emissions more effectively than other equally costly options.
Perhaps I’m misunderstanding, but this still seems inaccurate to me. If there is a more effective yet equally costly option O, but the total benefit of O+Vegetarian is still greater than the total cost of O+Vegetarian, then Vegetarian is still worth it (as is O). Your framing seems to deny this.
My original question was an attempt to ascertain whether the reduction in greenhouse gas emissions was truly your primary reason for choosing vegetarianism
Yes. It was, and is. I guess there’s an added benefit in terms of cost, but given that I don’t care about the animals themselves, I really don’t have any other reasons for it.
The (seemingly) more common animal welfare justification for vegetarianism seems more directly linked to the particular decision to not eat meat than does a carbon emissions argument.
Sure. But it would hard to get a more direct link than the animal welfare argument, so that’s not saying much. Something in the order of 20% of global GHG emissions can be attributed to livestock, so it’s not like the link between meat and emissions is weak.
I guess the complication is that there’s a reasonable amount of variation in emissions depending on what meat you’re talking about. Ruminants (cows, sheep) are especially bad (because of the methane), as is dairy (for the same reason). Farmed and deep sea fish are pretty bad too, but other fish are probably OK. Chicken (and especially eggs) aren’t so bad either (and are probably better the worse you treat the chickens).
Ultimately, I figured that it would be easier (and therefore more effective) to have a clear no meat rule than to try to make too many case-by-case calls that I might then be tempted to weasel out of. Nonetheless, in an effort to become slightly more consistent, I’ve made a deal with myself that I can start eating (OK) fish again if/when I manage to completely ditch the dairy (given that the latter is almost certainly worse from a GHG perspective). Haven’t quite managed it yet though.
Is that impression based on anything in particular? The evidence that it will reduce one’s individual carbon footprint seems fairly solid (see e.g. here) . The extent to which that translates, via reduced demand, into actual emission reductions is perhaps more arguable, but that doesn’t seem to be what you’re getting at. Conversely, there are rather more serious, and well-recognised concerns about the efficacy of offsets.
Actually, I think the fact that it’s possible to adapt pretty easily to a meat-free diet strengthens the case for others doing (or at least trying) it.
P.S. What makes you assume I’m male?