The heat storage capacity of Southern Ocean (SO) buffers future atmospheric warming but differs vastly across climate models. Reducing its projection uncertainty is vital for understanding and evaluating future global sustainability. Using Coupled Model Intercomparison Project Phase 6, we show that the present-day SO high-latitude easterly wind anomalies induced by El Niño is an effective constraint for the projected increase in SO heat content. Models simulating weaker El Niño-induced easterlies generate more equatorward atmospheric teleconnection in the present day. Under global warming, these models have greater capacity in the poleward shift of atmospheric circulation, thus generate stronger future increase in El Niño-induced high-latitude easterlies, slowing the SO heat storage by weakening the northward Ekman transport that underpins the dynamical process for SO heat storage. However, most models overestimate the present-day El Niño-induced easterlies, implying that alleviating this bias would reduce future SO heat storage, thus exacerbating atmospheric warming.

南大洋（SO）的储热能力可以缓冲未来的大气变暖，但在不同的气候模型中差异很大。减少预测的不确定性对于理解和评估未来全球可持续性至关重要。利用耦合模型比对项目第六阶段，我们表明，目前由厄尔尼诺现象引起的SO高纬度东风异常是对SO热含量预计增加的有效约束。模拟较弱的厄尔尼诺现象引起的东风的模型在当今会产生更多的赤道大气遥相关。在全球变暖的情况下，这些模型在大气环流向极地移动方面具有更大的能力，从而使厄尔尼诺引起的高纬度东风在未来产生更强劲的增加，通过削弱支撑SO2动力学过程的向北埃克曼传输来减缓SO2热储存蓄热。然而，大多数模型高估了当前厄尔尼诺现象引起的东风，这意味着减轻这种偏差将减少未来的二氧化硫热储存，从而加剧大气变暖。