There may already be data showing that a changing climate is adversely impacting key crops. That's what Stanford agricultural scientist David Lobell and his colleagues at the International Maize and Wheat Improvement Center (CIMMYT) discovered when they looked at "a hidden trove" of crop yield data from corn trials in Africa. They found that a temperature rise of a single degree Celsius would cause yield losses for 65 percent of the present maize-growing region in Africa – provided the crops received the optimal amount of rainfall. Under drought conditions, the entire maize-growing region would suffer yield losses, with more than 75 percent of areas predicted to decline by at least 20 percent for 1 degree Celsius of warming.
While crop yield trials are common in sub-Saharan Africa, weather information has not been commonly collected. The researchers were able to gather data from weather stations, with help from the World Meteorological Organization.
"I think we may just be scratching the surface of what can be achieved by combining existing knowledge and data from the climate and agriculture communities. Hopefully this will help catalyze some more effort in this area."
According to Lobell, similar sources of information elsewhere in the developing world could improve crop forecasting for other vast regions where data has been lacking.
"Projections of climate change impacts on food production have been hampered by not knowing exactly how crops fair when it gets hot. This study helps to clear that issue up, at least for one important crop."
CIMMYT is a core partner in the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS), which is combining climate science with agricultural science to understand how climate impacts food production, and come up with options for farmers to adapt to changing conditions.
The research is featured in the new journal Nature Climate Change (doi:10.1038/nclimate1043)