During the decade from 1996 to 2006, the world became accustomed to stable crop production levels. Production problems in one part of the world were balanced out by increased production elsewhere. In such a world it was easy to argue that reserves were unnecessary, because there would always be someone with a supply they were willing to export.

This year, hot weather in Eastern Europe and wet weather in the U.S. have resulted in the expectation of tighter crop supplies and higher prices. It was a similar yet different and more extreme scenario three years ago that led to a meteoric increase in crop prices that resulted in embargoes, food riots, and an increase in the number of hungry people in the world.

Is the crop production variability we have seen since 2006 the result of the normal forces or climate change? It is probably too soon to attribute these particular events to one cause or the other.

What we do know is that in the past we have seen decades like 1996 to 2006 with few widespread production problems and decades like the 1930s when they seem to happen on a regular basis. Climate change, we are told, has the potential to increase the variability and even result in a shift in global production areas.

Whatever the cause of erratic production problems, the policy that is needed to protect both producers and consumers is the same – reserves.