Joint forcing of climate warming and ENSO on a dual-cropping system.

Highlights • A dual-cropping system was presented to address the effects of climate change. • The dual-cropping system in the HP showed variable responses to climate warming. • Phenophases of crop growing period were shortened due to increasing temperature. • Precipitation anomalies induced by ENSO and AAO imposed a negative effect. • Potential risks arise from intensification of water stress and climate extremes. Abstract Challenges for achieving food security with an increasing world population are stimulating many stakeholders to consider the impact of climate change on global-regional crop production. One major concern is how the covariations of climate warming and extremes (e.g., ENSO) affect agricultural systems and production. Here, a dual-cropping system in the Huaihe Plain was used as a testbed to address this issue. We found that climate warming during 1982–2013 has produced remarkable influences on the dual-cropping agricultural system. For the spring season crop (i.e., winter wheat), a significant negative effect was found with a production loss of ˜6.9 × 106 tons due to an elevated T mean (˜2.21 °C) (r =-0.508, p < 0.01), which was associated with water stress. For the summer/autumn crops (i.e., rice and maize), a significant positive effect was found, but with a less substantial production gain (˜1.4 × 106 tons), supposedly due to the relaxed temperature constraints (an increased T max of ˜1.28 °C) for high heat resistant crops (r = 0.495, p < 0.01). The phenophase of the crop growing period was shortened by ˜7 days for the spring crop and by ˜4.4 days for the summer/autumn crops with enhanced thermal conditions. Precipitation anomalies, especially those associated with ENSO turning from El Niño to La Niña, imposed an additional serious impact on the dual-cropping system through decreased precipitation in the spring and increased precipitation in the summer/autumn. Potential impacts for the future could be derived from intensification of water and heat stresses, as well as the climate extremes (e.g., ENSO and AAO). [ABSTRACT FROM AUTHOR]