Variations in Mediterranean thermohaline circulation of the Quaternary are still not well constrained whereas they have been considered to have an influence on the Atlantic Meridional Overturning Circulation and on the oxygenation of waters in the deep basins of the Mediterranean Sea. εNd analyses have been carried out on planktonic foraminifera of cores collected in the central Mediterranean Sea to constrain water mass exchange between the Eastern and Western Mediterranean Sea (EMS and WMS) during the last climatic cycle. εNd records from the WMS and EMS display similar higher values during warm substages of interglacial Marine Isotopic Stage (MIS) 1 and 5. This suggests an efficient connection between the two Mediterranean sub‐basins and the transfer of radiogenic waters to the Tyrrhenian Sea via the Levantine Intermediate Water (LIW). Conversely, during glacial MIS, εNd of the intermediate depth of the Tyrrhenian Sea are less radiogenic than the EMS, implying limited hydrological connection between sub‐basins during low sea‐level stands. Superimposed on these glacial‐interglacial variations, increased εNd occurred during Heinrich Stadial events. This suggests a reduction in the formation of unradiogenic WIW in the Gulf of Lions due to the input of relatively fresh surface Atlantic water to the WMS and/or the inflow of radiogenic glacial LIW and upper EMDW to the Tyrrhenian Sea as a result of an active EMS convection related to saltier and colder conditions. Such potential millennial‐scale pulses of LIW intrusion into the Tyrrhenian Sea may have led to an enhanced Mediterranean Outflow Water intensity in the Gibraltar Strait.

中文翻译：

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最后一次气候周期中地中海中间水团的变化-有孔虫钕同位素的新约束

第四纪地中海热盐环流的变化仍然没有得到很好的限制，尽管它们被认为对大西洋子午线翻转环流和地中海深水域的水的氧化有影响。已对地中海中部采集的岩心的浮游有孔虫进行了εNd分析，以限制最后一个气候周期中东地中海和西地中海（EMS和WMS）之间的水质交换。来自WMS和EMS的εNd记录在冰间期海洋同位素阶段（MIS）1和5的温暖子阶段显示出相似的较高值。这表明两个地中海子盆地之间的有效联系以及放射源性水通过第一个向第勒尼安海的转移黎凡特中级水（LIW）。相反，在冰川期MIS期间，第勒尼安海中间深度的εNd不如EMS放射源，这意味着在低海平面站期间，各流域之间的水文联系有限。在这些海冰间变化的叠加下，海因里希（Heinrich）Stadial事件发生的εNd增加。这表明，由于活跃的活动，由于向WMS输入了相对较新的地表大西洋水和/或向第勒尼安海流入了放射源性冰川LIW和上部EMDW，导致了狮子湾非放射性WIW的形成减少。与更咸和更冷的条件有关的EMS对流。LIW侵入第勒尼安海的这种潜在的千年尺度脉动可能导致直布罗陀海峡的地中海流出水强度增加。