Establishing tropical sea surface temperature (SST) during the Last Glacial Maximum (LGM) is important for constraining equilibrium climate sensitivity to radiative forcing. Until now, there has been little data from the central equatorial Pacific in global compilations, with foraminiferal assemblage‐based estimates suggesting the region was within 1°C of modern temperatures during the LGM. This is in stark contrast to multi‐proxy evidence from the eastern and western Pacific and model simulations which support larger cooling. Here we present the first estimates of glacial SST in the central equatorial Pacific from Mg/Ca in Globigerinoides ruber. Our results show that the central Pacific cooled by about 2.0°C during the LGM, in contrast with previous global compilations but in agreement with models. Our data support a larger magnitude of tropical LGM cooling, and thus a larger equilibrium climate sensitivity, than previous studies which relied on foraminiferal assemblages in the central tropical Pacific.

中文翻译：

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上一次冰川最大爆发期间的中赤道太平洋冷却

在最后一次冰河期（LGM）期间建立热带海面温度（SST）对于限制平衡气候对辐射强迫的敏感性很重要。到目前为止，全球汇编中赤道中心太平洋的数据很少，基于有孔虫组合的估计表明该区域在LGM期间处于现代温度的1°C以内。这与东太平洋和西太平洋的多代理证据以及支持更大冷却的模型模拟形成鲜明对比。在这里，我们从Globigerinoides ruber中的Mg / Ca提出了赤道中太平洋冰川SST的初步估计。。我们的结果表明，与以前的全球统计数据相反，但与模型一致，在LGM期间太平洋中部地区冷却了约2.0°C。我们的数据表明，与以往依靠中部太平洋太平洋有孔虫组合的研究相比，热带LGM降温的幅度更大，因此对平衡气候的敏感性更高。