The New Geopolitics of Food (2)

The doubling of world grain prices since early 2007 has been driven primarily by two factors: accelerating growth in demand and the increasing difficulty of rapidly expanding production. The result is a world that looks different from the bountiful global grain economy of the last century. On the demand side, farmers nowfear clear sources of increasing pressure. The first is population growth. Every year the world's farmers must feed 80 million additional people, nearly all of them in developing countries. The world's population has nearly doubled since 1970 and is headed toward 9 billion by midcentury. Some 3 billion people are also trying to move up the food chain, consuming more meat, milk and eggs. As more families in China and elsewhere enter the middle class, they expect to eat better.
Everything from falling water tables to eroding soils and the consequences of global warming means that the worls's food supply is unlikely to keep up with our collectively  growing appetites. Take climate change: the rule of thumb among crop ecologists is that fore every 1 degree Celsius rise in temperature above the growing season optimumm farmers can expect a 10% decline in grain yields. The relationship was borne out all too dramatically during the 2010 heat wave in Russia, which reduced the country's grain harvest by nearly 40%.