Economists across the world are expressing concern about rising food prices. The United Nations Food and Agriculture Organization recently released its Food Price Index. The list showed that a number of foods cost more than during the world food crisis of two thousand eight. The index is at its highest level since it began in nineteen ninety.Demonstrations and deadly food riots broke out in January as they did in two thousand eight. The F.A.O. predicts that world market prices for rice, wheat, barley, sugar and meat will stay high or continue rising. One reason for this is the threat of shortages caused by bad weather. Current and recent weather disasters have harmed agriculture and affected prices in several parts of the world. For example, flooding in Australia has damaged crops in the usually fertile Queensland area. Chickpea, wheat, sorghum and corn are among the crops affected. Floods also have harmed other vegetables and fruits. Local agricultural producers report that standing water could destroy up to half of next year’s sugar crop. And economists say prices for the fruits and vegetables could likely increase over the next six months.The effects on prices from floods last year in Pakistan and China are still being felt.In January, Russia extended an earlier ban on wheat exports. Russia acted after heat, drought and wildfires destroyed about a third of its wheat crop last summer. The ban was placed to make sure Russians have enough wheat. The first ban caused worldwide wheat prices to climb last year by almost fifty percent. In Algeria, the government reduced taxes after food riots late last year and in January. Among the causes of the riots were price increases for cooking oil and sugar. Several people died in the riots, and hundreds of others were injured. Food prices are also part of the economic problems to blame for the deadly riots in Tunisia. Shenggen Fan heads the International Food Policy Research Institute from its Washington, D.C. office. Mr. Fan says countries must invest in making their farmers more productive. He says the world will need to feed more hungry people with less available land, water and other resources. For VOA Special English I’m Alex Villarreal.