An international team of scientists has developed new crop models to forecast food production as the population surges to nine billion by the mid-century and a warming climate drastically shifts agricultural patterns.

Researchers with the Agricultural Model Intercomparison and Improvement Project said their new modeling system integrates multiple crop simulations with updated climate change models, in order to better predict wheat production around the world. The modeling system takes into account political and socioeconomic factors that often skew data and planning efforts, according to Bruno Basso, an ecosystem researcher with Michigan State University, who worked on the project.

"Quantifying uncertainties is an important step to build confidence in future yield forecasts produced by crop models," Basso told reporters. "By using an ensemble of crop and climate models, we can understand how increased greenhouse gases in the atmosphere, along with temperature increases and precipitation changes, will affect wheat yield globally."

In the coming decades, food production on the continent with the fastest-growing population — Africa — will be most affected by global climate change, according to the United Nation's World Food Program. Also affected significantly will be the poorest parts of southern and southeastern Asia, with possible impacts to food production in Central America as well.

As climate shifts, a growing population will require global food production to increase by 50 percent by 2030, according to an analysis from the World Bank. Previous studies show that yields of wheat, rice, and maize would fall by nine to 11 percent, as temperatures rise and water supplies fall. Food prices around the world would rise by 25 to 150 percent as hunger rises by 10 to 60 percent, the UN projected in a 2009 report.

However, updated modeling suggests that small-scale adaptations — such as changing planting times — may help to alleviate hunger rates by as much as half. Ideally, governments around the world would respond in global fashion to "liberalize" world food trade, which experts say would cut hunger rates substantially.

To better model global crop yields, Basso and his colleagues developed the System Approach for Land-Use Sustainability model, as part of his university's global water initiative. The tool forecasts crop, soil, water, nutrient conditions, and other factors in present and future climate conditions. In addition, researches can also evaluate crop rotations, planting dates, irrigation and fertilizer use, and agricultural impact on the land.

"We can change the scenarios, run them simultaneously and compare their outcomes," Basso said. "It offers us a great framework to easily compare different land-management approaches and select the most efficient strategies to increase crop yield and reduce environmental impact such as nitrate leaching and greenhouse gas emission."

In the study, the researchers examined simulated yields from 27 different wheat crop models, forecasting through their new system the impact on changes when considering rising temperatures and changes in precipitation and carbon emissions.

The system has been used by researchers in several other projects monitoring grain crops and water use in troubled areas such as the Ogallala aquifer in the southeastern United States, in addition to areas in Russia, India, and Africa.

"I have the ambitious goal to enhance scientific knowledge for living in a better world, and hopefully with less poverty and enough food for the planet," Basso said.

Source: Asseng S, Ewert F, Rosenzweig C, Jones JW, Hatfield JL, Ruane A. Uncertainty in simulating wheat yields underclimate change. Nature Climate Change. 2013.