A recent article by George Monbiot explains one of the potential ramifications of diverting grains into fuel. Thanks to extreme weather around the globe:
”…this is also a year of food deficit, in which we will consume (31 million tons) more grain than farmers produced. If 2013′s harvest does not establish a new world record, the poor are in serious trouble.”
His main point is that thanks to a growing demand for food driven by an increasing population and improving standards of living, along with the conversion of grains into fuel, the world has to break harvest records every year to keep up. Thanks to grain reserves, humanity can weather years that don’t break records, but failing to break records for two or three years in a row means hunger for hundreds of millions because the price of food will spike as speculators capitalize on the fact that low supply relative to demand equates to higher prices. If weather extremes become more and more common, the odds of running out of reserves becomes more and more likely. (See more: Midwestern Drought, Ethanol, & Renewable Fuel Standard)
It is the prediction of things like mass starvation that help prevent things like mass starvation. This self-nullifying tendency is why a lot of predictions fail to materialize. Ignoring the prediction of massive traffic jams due to road construction could mean that you are the only one on the road because everyone else heeded the prediction, or it could mean that you are stuck in gridlock because you were not alone in ignoring it.