The worst drought for 50 years is inflicting huge damage on the US maize crop, with serious consequences for the overall international food supply.

The situation reminds us that even the most advanced agricultural systems are subject to the vagaries of the weather, leading to volatility in supplies and prices not just on domestic markets but also internationally. Climate change and extreme weather events will further complicate the picture.

US maize production had been expected to increase to record levels this year. That view will prove optimistic. Much of the reduced crop will be claimed by biofuel production in line with US federal mandates, leaving even less for food and feed markets. The August US Department of Agriculture estimates, announced today, will give a more precise idea for just how much the maize crop is reduced. Few people are expecting good news.