World food prices are back at levels last seen during the 2008 food crisis, when riots spurred bans on food exports in the most afflicted countries. The question now is whether the price surge of late 2010 will spill into 2011.

The U.N. Food and Agriculture Organization's index of world food prices rose 32 percent in the second half of 2010, topping the peak of June 2008.

Low rainfall in Russia, Kazakhstan, Europe, and South America parched crops, while floods in Canada inundated them. China's growth spurred record demand for sugar and soybeans.

Excessive rain in India has damaged the onion crop, driving the wholesale price of this staple up 40 percent in the 12 months ended Dec. 18. Developed countries' grain stocks — the reserves that keep consumption steady when harvests disappoint — will probably decline 25 percent in the 2010-11 crop year, according to the FAO.