The Atlantic Niño, a primary climatic variability mode in the equatorial Atlantic Ocean, exhibits pronounced variability not only in boreal summer but also in winter. However, the role of the winter Atlantic Niño in trans-basin interactions remains underexplored compared to its summer counterpart. Through analysis of observational reanalysis data since the mid-twentieth century, here we found that the winter Atlantic Niño significantly influences the development of El Niño–Southern Oscillation (ENSO), surpassing the impact of summer Atlantic Niño, with a longer lead time. This effect is reasonably captured in the CMIP6 Historical simulations from a multi-model ensemble perspective. Further analysis of the global warming scenario projects that the influence of winter Atlantic Niño on ENSO will persist into the future, in contrast to the reduced impact of summer Atlantic Niño. Therefore, these findings underscore the importance of further investigating the winter Atlantic Niño to gain a comprehensive understanding of trans-basin interactions and their future changes.

大西洋厄尔尼诺现象是赤道大西洋的主要气候变率模式，不仅在北半球夏季而且在冬季都表现出明显的变率。然而，与夏季相比，冬季大西洋厄尔尼诺现象在跨流域相互作用中的作用仍未得到充分研究。通过对20世纪中叶以来的观测再分析资料的分析，我们发现冬季大西洋尼诺对厄尔尼诺-南方涛动（ENSO）的发展影响显着，超过夏季大西洋尼诺的影响，且提前时间更长。从多模型集成的角度来看，CMIP6 历史模拟合理地捕捉到了这种效应。对全球变暖情景的进一步分析预计，冬季大西洋尼诺现象对 ENSO 的影响将持续到未来，而夏季大西洋尼诺现象的影响则有所减弱。因此，这些发现强调了进一步研究冬季大西洋尼诺现象以全面了解跨流域相互作用及其未来变化的重要性。