2025/07/28 by Lei Zhang, Yanying Chen, Kristopher B. Karnauskas +3 · 1 voice
Earth and Planetary Sciences · Environmental Science · Physics and Astronomy · #Climate variability and models #Ionosphere and magnetosphere dynamics #Tropical and Extratropical Cyclones Research
paper · pdf · doi:10.1038/s43247-025-02584-8
openalex publication_date 2025/07/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
The El Niño-Southern Oscillation is a major driver of global climate and weather variability through atmospheric teleconnections. However, the 2023/24 El Niño event, despite ranking as the fourth strongest since 1979, exhibited an unusually weak Pacific-North American pattern. Here we show that this unexpected behavior is due to anomalously weak tropical Pacific rainfall changes, a key driver of teleconnections associated with El Niño. Through analysis of observational data during 1979–2023 and performing atmospheric model experiments, we further reveal that the suppressed tropical Pacific rainfall changes were caused by unprecedented warming in the tropical Indian and Atlantic Oceans in 2023. This warming, partly driven by long-term trends exceeding those in the tropical Pacific, has amplified the influence of these extra-Pacific basins on El Niño dynamics. Notably, current climate models fail to reproduce this interbasin warming contrast, highlighting critical challenges in their ability to predict future climate impacts associated with El Niño events. Extreme sea surface temperature warming in the tropical Indian Ocean and Atlantic in 2023 suppressed the rainfall pattern induced by the 2023/24 El Niño, reducing its tropical and extra-tropical impacts, according to an analysis of climate reanalyses and model simulations over the period 1979-2023.