Here is my new New York Times column, about the tall task involved in doubling world food output by 2050:
The green revolution has slowed since the early 1990s, and it has become harder to bolster crop yields, as I have discussed in my book, “An Economist Gets Lunch.” And recent research by Dani Rodrik, a professor of international political economy at Harvard, indicates that agricultural productivity improvements are among the hardest to transmit from one nation to another.
In a recent address, Michael Lipton, an economist and research professor at Sussex University in Britain, offered a sobering look at Africa’s agricultural productivity. He suggests that Rwanda and Ghana are gaining, but that most of the continent is not. Production and calorie intake per capita don’t seem to be higher today than they were in the early 1960s. It remains an issue how Africa’s growing population will be fed.
There is no shortage of writing — often from a locavore point of view — in support of more organic methods of farming, for both developed and developing countries. These opinions recognize that current farming methods bring serious environmental problems involving water supplies, fertilizer runoff and energy use. Yet organic farming typically involves smaller yields — 5 to 34 percent lower, as estimated in a recent study in the journal Nature, depending on the crop and the context. For all the virtues of organic approaches, it’s hard to see how global food problems can be solved by starting with a cut in yields. Claims in this area are often based on wishful thinking rather than a hard-nosed sense of what’s practical.
I can’t stress that last sentence enough, and I find it amazing what passes for a good pro-organic argument in this area.
There is also an excellent recent essay by Jeremy Grantham on agriculture (pdf), too pessimistic in my view but still more right than wrong. For an interesting look at why future gains from GMOs may be limited, at least in the short run, read R. Ford Denison’s Darwinian Agriculture. Nature already has done a lot of the optimization.
The bottom line is this: right now agriculture is a laggard sector — in part due to state interventions — and this is not totally unrelated to recent headlines about unrest in the Middle East.