Age determination and paleotemperatures of sediment core MD95-2043 in the Alboran Sea

Past sea surface temperature (SST) evolution in the Alboran Sea (western Mediterranean) during the last 50,000 years has been inferred from the study of C37 alkenones in International Marine Global Change Studies MD952043 core. This record has a time resolution of ~200 years allowing the study of millennial-scale and even shorter climatic changes. The observed SST curve displays characteristic sequences of extremely rapid warming and cooling events along the glacial period. Comparison of this Alboran record with delta18O from Greenland ice (Greenland Ice Sheet Project 2 core) shows a strong parallelism between these SST oscillations and the Dansgaard-Oeschger events. Five prominent cooling episodes standing out in the SST profile are accompanied by an anomalous high abundance of Neogloboquadrina pachyderma sinistral which is confined to the duration of these cold intervals. These features and the isotopic record reflect drastic changes in the surface hydrography of the Alboran Sea in association with Heinrich events Hl-5.

过去5万年来阿尔沃兰海（西地中海）的海表温度（Sea Surface Temperature, SST）演化历程，可通过对国际海洋全球变化研究（International Marine Global Change Studies）MD952043岩芯中的C37烯酮类化合物开展分析得以反演。该记录的时间分辨率约为200年，足以支撑千年尺度乃至更短时间尺度的气候变化研究。观测到的海表温度曲线在冰期阶段呈现出一系列特征性的极速增温与降温事件序列。将该阿尔沃兰海记录与格陵兰冰芯（格陵兰冰盖计划2岩芯，Greenland Ice Sheet Project 2 core）中的δ¹⁸O记录进行对比后可见，海表温度振荡与丹斯果-奥什格尔事件（Dansgaard-Oeschger events）存在显著的同步性。海表温度序列中凸显出5个显著的降温事件，这些事件均伴随左旋厚壳新球虫（Neogloboquadrina pachyderma sinistral）丰度的异常升高，且该浮游有孔虫的高丰度仅局限于对应冷期的时段内。上述特征与同位素记录均反映出，阿尔沃兰海表层水文环境与海因里希事件（Heinrich events）Hl-5相关联的剧烈变化。