In 2007, drought struck the bread baskets of Europe, Russia, Canada, and Australia. Global grain stocks were already scant, so wheat prices began to rise rapidly. When countries put up trade barriers to keep their own harvests from being exported, prices doubled, according to an index of the Food and Agriculture Organization of the United…

About 175 nations agreed a plan Sunday to salvage climate talks after the Copenhagen summit but the U.N.’s top climate official predicted a full new treaty was out of reach for 2010. Delegates at the April 9-11 talks, marred by late-night wrangling between rich and poor nations on how to slow global warming, agreed to…