Diverging importance of drought stress for maize and winter wheat in Europe

TLDR

Understanding the drivers of yield levels under climate change is required to support adaptation planning and respond to changing production risks. The study employs an ensemble of crop models on a spatial grid to quantify how climatic drivers contributed to past yield variability in European grain maize and winter wheat (1984‑2009) and to project climate‑change impacts on yields by 2050. Climate change would cause yield losses for grain maize and gains for winter wheat; across Europe, heat stress does not increase for either crop in rainfed systems, but drought stress intensifies for maize only; in low‑yielding years, drought remains the main driver of losses for both crops, with elevated CO₂ offering no benefit.

Abstract

Understanding the drivers of yield levels under climate change is required to support adaptation planning and respond to changing production risks. This study uses an ensemble of crop models applied on a spatial grid to quantify the contributions of various climatic drivers to past yield variability in grain maize and winter wheat of European cropping systems (1984-2009) and drivers of climate change impacts to 2050. Results reveal that for the current genotypes and mix of irrigated and rainfed production, climate change would lead to yield losses for grain maize and gains for winter wheat. Across Europe, on average heat stress does not increase for either crop in rainfed systems, while drought stress intensifies for maize only. In low-yielding years, drought stress persists as the main driver of losses for both crops, with elevated CO2 offering no yield benefit in these years.