“Adaptation across the food system has great potential to manage climate-change effects on food security,” says the report. The many links in the food chain offer opportunities to buffer the impacts. Improved food processing and storage practices can stretch supplies by reducing food waste. Price increases would be lowest with freer trade in food. “The agricultural sector has a strong record of adapting to changing conditions. There are still many opportunities to bring more advanced methods to low-yield agricultural regions, but water and nutrient availability may be limiting in some areas as is the ability to finance expensive technologies,” said the paper.
“Climate Change, Global Food Security and the U.S. Food System,” says rising temperatures and shifting rainfall patterns worldwide are likely to slow progress against hunger. The UN Food and Agriculture Organization says the global hunger rate is 11%, down from nearly 19% in the early 1990s. Hunger rates are highest in sub-Saharan Africa, at 28%, while Asia has the largest number of hungry people, 500 million of the world total of 800 million.
Worst-case projections, based on high concentrations of greenhouse gases, rapid population growth, and low economic growth, “imply that the number of people at risk of undernourishment would increase by as much as 175 million above today’s level by 2080,” according to the paper, to be released by Agriculture Secretary Tom Vilsack at the UN climate conference. If the socioeconomic conditions remain the same and greenhouse gas concentrations rise to about 550 parts per million, compared to the current 400 ppm, the result would be “up to 60 million additional people at risk.” Scenarios with slower population growth and more robust economic growth indicate large reductions in food insecurity.
The U.S. is likely to see higher prices and a change in the types of food available for import, increased demand for food exports, and more calls from poor nations for food aid and other assistance. Three major challenges to global food supplies that would involve the U.S. food system would be closing yield gaps, increasing food production, and reducing food waste.
“Genetically modified crop varieties and the technological advances that produce them could play a significant role in increased food production in nations with large yield gaps, if they are suited to the local cultural, ecological, and economic situation,” says the paper. “Other technologies, such as high-efficiency irrigation methods and advanced mechanization and fertilization methods, can also contribute to reducing the yield gap.”
The U.S. agricultural system “is expected to be fairly resilient in the near term due to its capacity to undertake adaptive actions such as increased irrigation, shifting of crop rotations and acreage devoted to specific crops in some regions, and alteration of nutrient inputs and other management practices.” If temperatures increase by more than 3°C. and precipitation patterns change, “yields and farm returns are projected to decline. The continued changes expected between 2050 and 2100 under high-emissions scenarios are expected to have overall detrimental effects on most crops and livestock,” said the paper.