Pantropical climate interactions across ocean basins operate on a wide range of timescales and can improve the accuracy of climate predictions. Here, we show in observations that Central Pacific (CP) El Niño-like sea surface temperature (SST) anomalies have coevolved with tropical South Atlantic SST anomalies on a quasi-decadal (~10-year) timescale over the past seven decades. During the austral autumn–winter season, decadal warm SSTs in the tropical CP effectively induce tropical SST cooling in the South Atlantic, mainly by strengthening the South Atlantic subtropical anticyclone via an extratropical atmospheric wave teleconnection in the southern hemisphere. Partially coupled pacemaker simulations corroborate the observational findings, indicating that tropical CP decadal SSTs play a primary pacing role, while Atlantic feedback is of secondary importance throughout the study period. Our results suggest that the tropical CP could be an important source of decadal predictability for tropical South Atlantic SST and the surrounding climate.

跨海洋盆地的泛热带气候相互作用在广泛的时间尺度上运作，可以提高气候预测的准确性。在这里，我们在观测中表明，在过去七十年中，中太平洋 （CP） 类似厄尔尼诺现象的海面温度 （SST） 异常与热带南大西洋 SST 异常在准年代际（~10 年）时间尺度上共同进化。在南方秋冬季节期间，热带 CP 的年代际暖海温有效地诱导了南大西洋的热带海温降温，主要是通过南半球的温带大气波遥相关加强了南大西洋副热带反气旋。部分耦合的起搏器模拟证实了观测结果，表明热带 CP 年代际 SST 起主要起搏作用，而大西洋反馈在整个研究期间起次要作用。我们的结果表明，热带 CP 可能是热带南大西洋 SST 及其周围气候年代际可预测性的重要来源。