Challenges in understanding atmospheric responses to SSTs—an illustrative case of 2023/2024 winter Geophysical Research Letters

This study uses the 2023/2024 winter as a case study to analyze California precipitation response in atmospheric model simulations to illustrate the nuances in the response to variations in sea surface temperature (SST) anomalies during strong El Niño‐Southern Oscillation (ENSO) events. The 2024 El Niño exhibited a wet signal over California, but it was notably weaker. Observed SST anomalies for this winter included a contribution from SST warming trends and pronounced Atlantic warming that was much larger than attributable to SST warming trends alone. Sensitivity experiments indicated that SST trends suppressed California precipitation by disrupting traditional El Niño teleconnection patterns, particularly in southern California. Atlantic warming contributed to North Pacific anticyclonic anomalies, opposing typical El-Niño-induced wet conditions. These findings highlight the role of inter‐basin SST interactions and of trends in shaping atmospheric responses and underscore the importance of regional and global SST variations in modulating ENSO teleconnections. Grant no. NA24NESX432C0001