The people of East Africa once again face a devastating drought this year: Crops wither and fail from Kenya to Ethiopia, livestock drop dead and famine spreads. Although, historically, such droughts are not uncommon in this region, their frequency seems to have increased in recent years, raising prices for staple foods, such as maize.
This scenario may simply be a taste of a world undergoing climate change in the mid–21st century, according to a new report from the International Food Policy Research Institute (IFPRI), a Washington, D.C.–based organization seeking an end to hunger and poverty through appropriate local, national and international agricultural policies. By IFPRI's estimate, 25 million more children will be malnourished in 2050 due to the impact of climate change on global agriculture.
"Higher temperatures and changes in precipitation result in pressure on yields from important crops in much of the world," says IFPRI agricultural economist Gerald Nelson, an author of the report, "Climate Change, Agriculture, and Food Security: Impacts and Costs of Adaptation to 2050". "Biological impacts on crop yields work through the economic system resulting in reduced production, higher crop and meat prices, and a reduction in cereal consumption. This reduction means reduced calorie intake and increased childhood malnutrition."
Nelson and his colleagues, working with funding from the World Bank and Asian Development Bank, estimated global agricultural impacts by pairing IFPRI's own economic models for crop yields with climate models for precipitation and temperature from the U.S. National Center for Atmospheric Research and Australia's Commonwealth Scientific and Industrial Research Organization. Assuming a world that is slow to adapt to climate change and focused on regional self-reliance, the researchers found that children in the developing world—which are the countries expected to provide the bulk of population growth to nine billion or more by mid-century—will be hardest hit.
"It's not economic development that matters in this case, it's the location on the surface of the Earth," Nelson notes. Without better crop varieties or other agricultural technology improvements, irrigated wheat yields, for example, will fall at least 20 percent by 2050 as a result of global warming, and south Asia as well as parts of sub-Saharan Africa will face the worst effects.
Even without climate change, population pressure alone will cause a spike in food prices without intervention, according to IFPRI's economic model. For example, without climate change, wheat prices might rise from $113 per metric ton in 2000 to $158 per metric ton in 2050—an increase of 39 percent. Similarly, rice prices would soar by 62 percent, maize by 63 percent. But factoring in climate change will boost wheat prices by at least 170 percent and rice by a minimum of 113 percent; the cost of maize will be at least 148 percent higher than at the turn of the century by mid-century.
Nor will the developed world go unscathed. Research published in the Proceedings of the National Academies of Science in August noted that corn, soybean and cotton yields in the U.S. will drop precipitously because of additional days where the temperature is above 30 degrees Celsius.
Part of the problem is that the benefits of better plant growth, thanks to higher carbon dioxide concentrations (plants use CO2 for photosynthesis) are more than offset by the impact of higher temperatures and differing precipitation. "If you grow a plant in a bell jar in a lab and increase the CO2 inside, the plants will perform better. [But] will those results translate into farmer's fields? Evidence that we've been getting from farmer's fields suggests perhaps not," Nelson says. And that means fewer calories per person would be available in 2050.
To prevent this agricultural crisis, Nelson estimates, would require an investment of at least $7 billion per year in the most affected countries in Asia, Africa and Latin America for increased agricultural research into, for example, drought-resistant crop varieties. "Crop and livestock productivity–enhancing research, including biotechnology, will be essential to help overcome stresses due to climate change," the report's authors wrote.
These areas will also need expanded rural road and irrigation infrastructure as well as improvements to the efficiency of that irrigation.