From the NYT:

In an “unforeseen and unprecedented” shift, the world food supply is dwindling rapidly and food prices are soaring to historic levels, the United Nations’ top food and agriculture official warned Monday.

The changes created “a very serious risk that fewer people will be able to get food,” particularly in the developing world, said Jacques Diouf, head of the United Nations Food and Agriculture Organization.

The agency’s food price index rose by more than 40 percent this year, compared with 9 percent the year before — a rate that was already unacceptable, Mr. Diouf said. New figures show that the total cost of food imported by the neediest countries rose 25 percent in the last year, to $107 million.

At the same time, reserves of cereals are severely depleted, the agency’s records show. World wheat stores declined 11 percent this year, to the lowest level since 1980. That corresponds with 12 weeks of the world’s total consumption, much less than the average of 18 weeks’ consumption, in storage during the 2000-2005 period.

There are only 8 weeks of corn left, down from 11 weeks in the same five-year period.

Prices of wheat and oilseeds are at record highs, Mr. Diouf said Monday. Wheat prices have risen by $130 a ton, or 52 percent, since a year ago. United States wheat futures broke $10 a bushel for the first time Monday, a psychological milestone.

Mr. Diouf said the crisis was a result of a confluence of recent supply and demand factors that, he said, were here to stay.

On the supply side, the early effects of global warming have decreased crop yields in some crucial places. So has a shift away from farming for human consumption to crops for biofuels and cattle feed. Demand for grain is increasing as the world’s population grows and more is diverted to feed cattle as the population of upwardly mobile meat-eaters grows.

“We’re concerned that we are facing the perfect storm for the world’s hungry,” said Josette Sheeran, executive director of the World Food Program, in a telephone interview. She said that her agency’s food procurement costs had gone up 50 percent in the last five years and that some poor people were being “priced out of the food market.”