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Sortable silt particle-size data and stable isotope analyses from the Corsica Trough, western Mediterranean Sea, provide a continuous palaeoceanographic record of the inflow, ventilation and vertical fluctuations of the Levantine Intermediate Water (LIW) in the northern Tyrrhenian Sea for the last 130,000 years. The results presented herein reveal that climate changes drive the Mediterranean intermediate circulation on Milankovitch to millennial timescales. Intensified intermediate inflow and ventilation in the Corsica Trough occurred throughout the last glacial interval, with a cold/fasterwarm/slower pattern existing between the Dansgaard-Oeschger climatic oscillations (including Heinrich events) and the LIW variability. By contrast, a weak intermediate ventilation characterised the Holocene and the Last Interglacial period, especially during insolation maxima and the sapropel deposition in the eastern Mediterranean. This variability probably reflects the changes of the eastern Mediterranean net evaporation, as well as the propagation to the western Mediterranean of the profound hydrographic adjustments of the Levantine Sea and adjacent areas to climate forcing. The implications for the formation and ventilation of the Western Mediterranean Deep Water (WMDW) in the northwestern Mediterranean basin, as well as for Mediterranean-Atlantic exchange through the Strait of Gibraltar are discussed. Highlights ► The LIW dynamics in the Corsica Trough is reconstructed for the last 130,000 years. ► Climate changes drive the LIW dynamics on Milankovitch to millennial timescales. ► A cold/fasterwarm/slower pattern exists between climate and the LIW variability. ► Role of LIW in deep-water formation and Mediterranean-Atlantic exchange is examined.

Sediments cored along the southwestern Iberian margin during Integrated Ocean Drilling Program Expedition 339 provide constraints on Mediterranean Outflow Water (MOW) circulation patterns from the Pliocene epoch to the present day. After the Strait of Gibraltar opened (5.33 million years ago), a limited volume of MOW entered the Atlantic. Depositional hiatuses indicate erosion by bottom currents related to higher volumes of MOW circulating into the North Atlantic, beginning in the late Pliocene. The hiatuses coincide with regional tectonic events and changes in global thermohaline circulation (THC). This suggests that MOW influenced Atlantic Meridional Overturning Circulation (AMOC), THC, and climatic shifts by contributing a component of warm, saline water to northern latitudes while in turn being influenced by plate tectonics.