During the last glacial period, climate conditions in the North Atlantic region were determined by the alternation of relatively warm interstadials and relatively cool stadials, with superimposed rapid warming (Dansgaard‐Oeschger) and cooling (Heinrich) events. So far little is known about the impact of these rapid climate shifts on the seasonal variations in sea surface temperature (SST) within the North Atlantic region. Here, we present a high‐resolution seasonal SST record for the past 152 kyrs derived from Integrated Ocean Drilling Program “Shackleton” Site U1385, offshore Portugal. Assemblage counts of dinoflagellates cysts (dinocysts) in combination with a modern analog technique (MAT), and regression analyses were used for the reconstructions. We compare our records with previously published SST records from the same location obtained from the application of MAT on planktonic foraminifera. Our dinocyst‐based reconstructions confirm the impression of the Greenland stadials and interstadials offshore the Portuguese margin and indicate increased seasonal contrast of temperature during the cold periods of the glacial cycle (average 9.0 °C, maximum 12.2 °C) with respect to present day (5.1 °C), due to strong winter cooling by up to 8.3 °C. Our seasonal temperature reconstructions are in line with previously published data, which showed increased seasonality due to strong winter cooling during the Younger Dryas and the Last Glacial Maximum over the European continent and North Atlantic region. In addition, we show that over longer time scales, increased seasonal contrasts of temperature remained characteristic of the colder phases of the glacial cycle.

中文翻译：

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“沙克尔顿遗址”U1385​​ 过去约 150 公里的千禧年尺度气候变率和基于甲藻包囊的季节性变化。

在末次冰期期间，北大西洋地区的气候条件是由相对温暖的间质层和相对凉爽的间质层的交替决定的，并叠加快速变暖（Dansgaard-Oeschger）和变冷（Heinrich）事件。迄今为止，人们对这些快速气候变化对北大西洋地区海面温度（SST）季节性变化的影响知之甚少。在这里，我们展示了来自葡萄牙近海综合海洋钻探计划“沙克尔顿”站点 U1385​​ 的过去 152 公里的高分辨率季节性海表温度记录。甲藻包囊（甲藻）的组合计数与现代模拟技术（MAT）相结合，并使用回归分析进行重建。我们将我们的记录与之前发布的同一地点的 SST 记录进行比较，该记录是通过对浮游有孔虫应用 MAT 获得的。我们基于恐龙囊的重建证实了葡萄牙边缘近海格陵兰岛的斯塔迪尔和间质的印象，并表明在冰川周期的寒冷时期（平均 9.0 °C，最高 12.2 °C）相对于现在的温度季节对比有所增加（ 5.1 °C），由于冬季强烈降温高达 8.3 °C。我们的季节性温度重建与之前发布的数据一致，该数据显示，由于欧洲大陆和北大西洋地区新仙女木期和末次盛冰期期间的冬季强烈降温，季节性有所增加。此外，我们发现，在较长的时间尺度上，温度的季节对比增加仍然是冰川周期较冷阶段的特征。