Changing temperatures are helping corn production in US—for now
https://phys.org/news/2018-11-temperatures-corn-production-usfor.html
"Our research shows that improvements in crop yield depend, in part, on improvements in climate," said Peter Huybers, Professor of Earth and Planetary Sciences in the Department of Earth and Planetary Sciences (EPS) and of Environmental Science and Engineering at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS). "In this case, changing temperatures have had a beneficial impact on agricultural production, but there is no guarantee that benefit will last as the climate continues to change. Understanding the detailed relationships between climate and crop yield is important as we move towards feeding a growing population on a changing planet."
The research is published in the Proceedings of the National Academy of Sciences (PNAS).