The Southern Ocean provides dominant contributions to global ocean heat and carbon uptake, which is widely interpreted as resulting from its unique upwelling and circulation. Here we show a large asymmetry in these contributions, with the Southern Ocean accounting for 83 ± 33% of global heat uptake versus 43 ± 3% of global ocean carbon uptake over the historical period in state-of-the-art climate models. Using single radiative forcing experiments, we demonstrate that this historical asymmetry is due to suppressed heat uptake by northern oceans from enhanced aerosol forcing. In future projections, such as SSP2-4.5 where greenhouse gases increasingly dominate radiative forcing, the Southern Ocean contributions to global heat and carbon uptake become more comparable, 52 ± 5% and 47 ± 4%, respectively. Hence, the past is not a reliable indicator of the future, with the northern oceans becoming important for heat uptake while the Southern Ocean remains important for both heat and carbon uptake.

南大洋对全球海洋热量和碳吸收做出了主要贡献，这被广泛解释为其独特的上升流和环流的结果。在这里，我们显示了这些贡献的巨大不对称性，在最先进的气候模型中，南大洋占历史时期全球热量吸收的 83 ± 33%，而海洋碳吸收则占 43 ± 3%。通过单一辐射强迫实验，我们证明了这种历史上的不对称性是由于气溶胶强迫增强而抑制了北部海洋的热量吸收。在未来的预测中，例如 SSP2-4.5，其中温室气体日益主导辐射强迫，南大洋对全球热量和碳吸收的贡献变得更具可比性，分别为 52 ± 5% 和 47 ± 4%。因此，过去并不是未来的可靠指标，北大洋对于热量吸收变得重要，而南大洋对于热量和碳吸收仍然很重要。