Super El Niño events drive climate regime shifts with enhanced risks under global warming

Abstract

Climate regime shifts (CRSs), characterized by abrupt and persistent transitions between alternative stable states in the climate system, pose serious threats to ecosystems and human well-being. Understanding the potential drivers of CRSs is crucial, particularly in a warming world where CRSs are becoming more frequent. Here, using multiple observations and model simulations, we find that the likelihood of CRS occurrence significantly increases in the context of super El Niño events due to their remarkable climate perturbations. This higher probability is detected across various climate elements, such as surface air temperature, sea surface temperature, and surface soil moisture. In addition, we suggest that this boost effect of super El Niño events on CRSs will be greatly amplified under future greenhouse warming. Our findings underscore a deeper and more persistent climate footprint of super El Niño events, suggesting that early warnings and proactive measures are crucial for mitigating their escalating risks.