Climate variability and simultaneous breadbasket yield shocks as observed in long-term yield records

• Published in: Agricultural and Forest Meteorology
• Main Authors: Anderson, Weston B., Baethgen, Walter E., Capitanio, Fabian, Ciais, Philippe, Cook, Benjamin I., Cunha, Cunha G.Rda, Goddard, Lisa, Schauberger, Bernhard, Sonder, Kai, Podestá, Guillermo, van der Velde, Marijn, You, Liangzhi
• Other Authors: Columbia University New York, Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Columbia University's World Projects; Socioeconomic Data and Applications Center
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2023
• Subjects: Climate variability; El Niño Southern Oscillation; Indian Ocean Dipole; Maize and wheat yield; Multiple breadbasket failures; North Atlantic oscillation; [SDV.SA]Life Sciences [q-bio]/Agricultural sciences; [SDV.EE.BIO]Life Sciences [q-bio]/Ecology; environment/Bioclimatology; North Atlantic
• Online Access: https://hal.science/hal-04069249; https://hal.science/hal-04069249/document; https://hal.science/hal-04069249/file/1-s2.0-S0168192323000151-main.pdf; https://doi.org/10.1016/j.agrformet.2023.109321

International audience That climate variability and change can potentially force multiple simultaneous breadbasket crop yield shocks has been established. But research quantifying the mechanisms behind such simultaneous shocks has been constrained by short records of crop yields. Here we compile a dataset of subnational crop yields in 25 countries dating back to 1900 to study the frequency and trends in multiple breadbasket yield shocks and how large-scale climate anomalies on interannual timescales have affected multiple breadbasket yield shocks over the last century. We find that major simultaneous breadbasket yield shocks have occurred in at least three, four, or five of nine breadbaskets 10.3%, 2.3% and 1.1% of the time for maize and 18.4%, 4.6% and 2.3% of the time for wheat. Furthermore, we find that multiple breadbasket yield shocks decreased in frequency even as those breadbaskets experience increasingly frequent climate-related shocks. For both maize and wheat breadbaskets, there were fewer simultaneous yield shocks during the 1975–2017 time period as compared to 1931–1975. Finally, we find that interannual modes of climate variability - such as the El Niño Southern Oscillation (ENSO), the Indian Ocean Dipole (IOD), and the North Atlantic Oscillation (NAO) - have all affected the relative probability of simultaneous yield shocks in pairs of breadbaskets by up to 20–40% in both maize and wheat breadbaskets. While past literature has focused on the effects of ENSO, we find that at the global scale the NAO affects the overall number of wheat yield shocks most strongly despite only affecting northern hemisphere breadbaskets.