Impacts of changes in climate extremes on maize yields over Mainland China

Climate change has increased the frequency and severity of climate extremes, but the influencing magnitudes of climate extreme events on maize yield in China remain unclear. Here, the impact of climate extremes on maize yield over Mainland China during the past four decades is assessed based on the concurrence of climate extremes (mean climate) and maize yields using the event coincidence analysis. Climate extremes during the maize growing season are represented by 14 extreme climate indices. Results showed that 95% of maize planting regions over Mainland China showed significant increases in maize yields, with an average increase of 0.071 t ha⁻¹ year⁻¹ from 1982 to 2016. Correlations between maize yields and climate indices are spatially heterogeneous. The area where maize is significantly affected by temperature extremes changes (2.7–15.4% of grids) is greater than the area affected by precipitation extremes (3.8–10.7% of grids). Positive maize yield events are more likely to coincide with positive temperature extremes and negative precipitation extremes. The proportion of years with significant events coincidence rates between positive yield events and positive evapotranspiration events is the highest, accounting for 94.29%. Our results implied that to adapt to the impact of climate events on maize yield, reliable extreme climate projection and maize planting growth season adjustment are required to ensure food security.