Fractional abundances of isoprenoid and branched glycerol dialkyl glycerol tetraethers (GDGT) of cores SO201-2-12KL and SO201-2-114KL

It has been proposed that North Pacific sea surface temperature (SST) evolution was intimately linked to North Atlantic climate oscillations during the last glacial-interglacial transition. However, during the early deglaciation and the Last Glacial Maximum, the SST development in the subarctic northwest Pacific and the Bering Sea is poorly constrained as most existing deglacial SST records are based on alkenone paleothermometry, which is limited prior to 15 ka B.P. in the subarctic North Pacific realm. By applying the TEXL86 temperature proxy we obtain glacial-Holocene-SST records for the marginal northwest Pacific and the Western Bering Sea. Our TEXL86-based records and existing alkenone data suggest that during the past 15.5 ka, SSTs in the northwest Pacific and the Western Bering Sea closely followed millennial-scale climate fluctuations known from Greenland ice cores, indicating rapid atmospheric teleconnections with abrupt climate changes in the North Atlantic. Our SST reconstructions indicate that in the Western Bering Sea SSTs drop significantly during Heinrich Stadial 1 (HS1), similar to the known North Atlantic climate history. In contrast, progressively rising SST in the northwest Pacific is different to the North Atlantic climate development during HS1. Similarities between the northwest Pacific SST and climate records from the Gulf of Alaska point to a stronger influence of Alaskan Stream waters connecting the eastern and western basin of the North Pacific during this time. During the Holocene, dissimilar climate trends point to reduced influence of the Alaskan Stream in the northwest Pacific.已有研究指出，末次冰期-间冰期过渡阶段的北太平洋海表温度（Sea Surface Temperature, SST）演化过程与北大西洋气候振荡存在紧密联系。然而在冰消期早期与末次冰盛期（Last Glacial Maximum）阶段，北太平洋亚北极西北海域与白令海的SST演化约束程度极低——这是由于当前多数冰消期SST记录均基于烯酮古温计（alkenone paleothermometry），而该方法在北太平洋亚北极区域15 ka B.P.之前的时段存在应用局限。本研究通过应用TEXL86温度代用指标（TEXL86 temperature proxy），获取了西北太平洋边缘海域与白令海西部的冰期-全新世SST记录。基于TEXL86的记录与已有的烯酮古温计数据表明，在过去15.5 ka期间，西北太平洋与白令海西部的SST变化紧密跟随格陵兰冰芯记录所揭示的千年尺度气候波动，这表明该区域与北大西洋突发性气候变化间存在快速大气遥相关作用。本研究的SST重建结果显示，白令海西部的SST在海因里希 Stadial 1（Heinrich Stadial 1, HS1）期间出现显著下降，这与已知的北大西洋气候历史特征相似。与之形成对比的是，西北太平洋的SST呈现逐步上升的趋势，这与HS1期间的北大西洋气候演化特征截然不同。西北太平洋SST与阿拉斯加湾气候记录间的相似性，暗示彼时连接北太平洋东西海盆的阿拉斯加流（Alaskan Stream）水体对该区域的影响更为显著。进入全新世之后，两者间的气候趋势差异表明，阿拉斯加流对西北太平洋的影响有所减弱。