Iberian Margin sea surface temperature during MIS 15 to 9 (580–300 ka): Glacial suborbital variability versus interglacial stability
Iberian Margin sea surface temperature during MIS 15 to 9 (580–300 ka): Glacial suborbital variability versus interglacial stability
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DOI：
10.1029/2010pa001927
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发表时间：
2010-12
期刊：
影响因子：
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通讯作者：
T. Rodrigues;A. Voelker;J. Grimalt;F. Abrantes;F. Naughton
中科院分区：
文献类型：
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作者：
T. Rodrigues;A. Voelker;J. Grimalt;F. Abrantes;F. Naughton
[1]基于里斯本北部Estremadura Spur海洋深海岩芯MD03-2699的生物标志物分析，重建了西伊比利亚边缘过去的海表水条件，为海洋同位素阶段（MIS） 15至MIS 9 （580 ~ 300 ka）的轨道和亚轨道尺度气候变化提供了新的认识。我们使用基于生物标志物的代理记录，如烯酮不饱和指数来估计海表温度（SST），总烯酮浓度来重建浮游植物生产力，以及陆地生物标志物来评估大陆输入。研究结果将现有的生物标志物记录，即伊比利亚边缘的海温，延长到第六个气候周期（580 ka）。稳定间冰期的一般趋势与以高频变率为特征的冰期和冰川开始期形成对比。因此，几次短暂的气候变冷可以通过海温的大幅下降、冰筏碎屑的出现和四不饱和烯酮C37:4的高百分比来确定。其中一些事件非常寒冷，其总体趋势与最后一次冰期著名的海因里希事件相似。我们确定了580至300 ka之间的8个heinrich型事件。在MIS 15和MIS 9之间检测到的总体消冰模式与表征最近气候周期的总体趋势相似，即以两次冷却为标志，中间间隔着短暂的变暖事件，这可能反映了极锋向南、向北和向南的迁移。
[1] Past sea surface water conditions of the western Iberian Margin were reconstructed based on biomarker analyses of a marine deep sea core MD03-2699 from the Estremadura Spur north off Lisbon, providing new insights into orbital and suborbital-scale climate variability between marine isotope stage (MIS) 15 to MIS 9 (580 to 300 ka). We use biomarker-based proxy records such as the alkenone unsaturated index to estimate sea surface temperature (SST), the total alkenone concentration to reconstruct phytoplankton productivity, and terrestrial biomarkers to evaluate the continental input. The results extend the existing biomarker record, namely the SST for the Iberian Margin, back to the sixth climatic cycle (580 ka). A general trend of stable interglacials contrasts with glacial periods and glacial inceptions which are marked by high-frequency variability. Thus, several short-lived climatic coolings were identified by large SST decreases, the occurrence of ice-rafted detritus and high percentages of the tetraunsaturated alkenone C37:4. Some of these events were extremely cold and similar in their general trends to the well-known Heinrich events of the last glaciation. We identified eight Heinrich-type events between 580 and 300 ka. The general deglaciation pattern detected between MIS 15 and MIS 9 is similar in their general trends to that characterizing the more recent climatic cycles, i.e., marked by two coolings separated by a short warming episode which may reflect the southward, northward, and southward migration of the Polar Front.