One of the possibilities for GW-damage is reductions in crop yield – up to 25%, in extreme scenarios. My reaction to that was “we all eat too much anyway” (well I certainly do) but some people did point out the obvious, that not everyone lives in the overfed West. Eli was kind enough to point to the FAO who tell me that in 2000 global average calories per day per person was 2807 (up from 24xx in 1970). The NHS tells me that the average adult should eat about 2,000 per day (women) and 2,500 per day (men) which we’ll average down to about 2,250 (m/f) and then down to 2000 (including children).
Which seems to count out to there being, globally, about 1/3 more food available than is needed (neglecting trivia like distribution and ability to pay). So there seems to be a fair amount of fat in the system (so to speak). And thats neglecting gains to be made from switching from inefficient meat-based nutrition to all going veggie.
[Update: Mind you, thisisn't good -W]