Global Warming to Cause Food Shortages

Half of the world’s population could face severe food shortages by the end of this century as rising temperatures shorten the growing season in the tropics and subtropics, increase the risk of drought, and reduce the harvests of dietary staples such as rice and maize by 20 percent to 40 percent, according to a study published in the journal Science.

Global warming is expected to affect agriculture in every part of the world but it will have a greater impact in the tropics and subtropics, where crops are less able to adapt to climate change and food shortages are already starting to occur due to rapid population growth.

High Highs

Scientists at Stanford University and the University of Washington, who worked on the study, discovered that by 2100 there is a 90 percent chance that the coolest temperatures in the tropics during the growing season will be higher than the hottest temperatures recorded in those regions through 2006. Even more temperate parts of the world can expect to see previously record-high temperatures become the norm.

Higher Demand

With the world population expected to double by the end of the century, the need for food will become increasingly urgent as rising temperatures force nations to retool their approach to agriculture, create new climate-resistant crops, and develop additional strategies to ensure an adequate food supply for their people.

All of that could take decades, according to Rosamond Naylor, who is director of food security and the environment at Stanford. Meanwhile, people will have fewer and fewer places to turn for food when their local supplies begin to run dry.

"When all the signs point in the same direction, and in this case it's a bad direction, you pretty much know what's going to happen," said David Battisti, the University of Washington scientist who led the study. "You're talking about hundreds of millions of additional people looking for food because they won't be able to find it where they find it now.

Member of the International Panel on Climate Change agree. In their latest review of the food security issue, they point out that it's not just crops: fisheries, weed control, food processing and distribution will all be affected.