Projected ENSO influences on global crop yields using a climate-crop model ensemble

The El Niño-Southern Oscillation (ENSO) will remain the major mode of natural climate variability in a warmer climate. However, how its impacts on crop yields may change under future climate change remains uncertain. Here, we present projected ENSO impacts on yields of maize, wheat, rice and soybean in the middle (2035-2064) and end (2065-2094) of the 21st century under low (Shared Socioeconomic Pathway [SSP] 1-2.6) and high (SSP5-8.5) warming scenarios. The recent climate-crop model ensemble we used (consisting of 12 global gridded crop models [GGCMs], provided by the Agricultural Model Intercomparison and Improvement Project [AgMIP]’s Global Gridded Crop Model Intercomparison [GGCMI] and the Intersectoral Impact Model Intercomparison [ISIMIP] project phase 3) successfully captured the observed major characteristics in the geographical spatial patterns of ENSO-induced yield changes, especially for wheat in La Niña years and for maize and soybean in both El Niño and La Niña years. However, its ability was low for rice. The relatively localized distribution of rice cultivation may limit the model ensemble’s ability to capture ENSO-driven yield variability. Overall, the results indicate that ENSO will continue to be a major driver of global yield variability. The negative impacts of El Niño on maize in eastern Brazil and the positive impacts in Argentina are projected to persist across all warming levels, whereas the negative impact on soybean yields in India may vary depending on the warming level. Yet, substantial uncertainties remain in the projected ENSO impacts, emphasizing the need to improve both climate and crop models to better prepare cropping systems for ENSO-related risks in a warmer climate.