Earlier quoted context omitted.
3) Shipping is cheap. No, thats an externality you don't care about. Its not cheap in social consequence terms. hauling food by road from centralized warehouses is a twofold sin. Firstly, its food miles and NO, CO2 and other burdens. Secondly, its why e coli spreads across the USA: too much centralisation of distribution. "cheap" food is actually at root, the problem. It needs to be affordable, but high quality. We'r…
It costs less in CO2 costs to ship a leg of lamb from New Zealand to a supermarket in Los Angeles than it does for you to get in a car and bring that lamb home with you. It also costs less in CO2 costs to ship that lamb from NZ to a supermarket than to truck it in from a local farm to your fancy organic farmer's market. If you want to attack CO2 costs, the primary costs are in the last mile.
If you want to attack CO2 costs, 90% of lamb's CO2 production occurs on the farm. Only 10% is from processing, distribution, retail, cooking, and waste disposal [1].
Let's charitably assume 1/3 of the post-farm CO2 emissions are from distribution and half of those could be saved by producing closer to the point of consumption.
So farm production only needs to be 1.8% (=(10/3/2)/90) more efficient in NZ for it to be net beneficial.
Presumably NZ is particularly efficient for lamb, otherwise it wouldn't be such a major export.
[1] To pick one reasonably creditble data source, see: https://en.wikipedia.org/wiki/Environmental_impact_of_meat_p... which ends with this graph: https://s3-us-west-2.amazonaws.com/webcitation/419e58a77a34f...