I recently covered Stephen Emmott's one-man show Ten Billion, a millennarian lecture designed to frighten its audience into reproducing less, consuming less and generally living less.
The show is now the subject of a thorough fisking by BH regulars Geoff Chambers and Alex Cull at the Climate Resistance site.
Googling “3000 litres of water to make a hamburger” leads us to sites like waterfootprint.org, which cite the peer reviewed articles (e.g. Mekonnen & Hoekstra: A Global Assessment of the Water Footprint of Farm Animal Products) which are the ultimate source of these figures. The high water content of hamburgers is explained by counting the rain falling on the grass or other crops consumed by the cow. It could be pointed out in defense of the Big Mac that even if you abolished livestock rearing and went back to hunter gathering, the same amount of rain would still fall on the same amount of grassland, and your voleburger would still have the same water footprint, though presumably without mustard and mayonnaise. It really doesn’t matter whether Mekonnen and Hoekstra have done their sums right; it’s not science – just a Reader’s Digest-style factoid to bring out to impress your dinner party guests over the home-grown roquette quiche.
Stephen Emmott is professor of computer science at Oxford.