Indeed, the ADB report is only the latest in a series of papers arguing that climate changes related to emissions will reduce world food production. The Food and Agriculture Organization of the United Nations has warned of increased risk of crop failures from floods and other weather changes, as well as the emergence of new pests and diseases that only flourish at specific temperatures and humidity.

　　Some agricultural experts believe Southeast Asia still has room to expand production of rice and other crops, especially in parts of Cambodia and Laos that have traditionally had low yields, but could be lifted by more investment in irrigation and better seed varieties. Rice prices have fallen dramatically this year after spiking in 2008, in part because some countries, including Indonesia, already have boosted production.

　　But many economists believe those gains will be hard to sustain in the long run without billions of dollars in new spending on farming infrastructure, and many fear a new surge in food prices could occur once the world economy recovers from its current recession and consumer demand accelerates.

　　Smith Dharmasaroja, a Thai meteorologist and climate-change expert, said rice farmers might be able to mitigate some damage from weather changes by improving water storage to capture more rain during wet seasons. But there will still 'definitely' be a decrease in rice production as summers become hotter, he said.