The upper Mediterranean Outflow Water (MOW) paleo-oceanographic history in the Gulf of Cadiz is poorly constrained due to the lack of high-resolution records that pre-date the last glaciation. Existing proxy records concentrate on MOW variability along the middle slope of the Gulf of Cadiz. Here we present a continuous high-resolution benthic foraminifera d18O record from the upper MOW core at IODP Expedition 339 Site U1386 in the Gulf of Cadiz of the past 150000 years. Based on d18O, grain-size and Zr/Al variability comparison of our results with existing Mediterranean Sea (MD01-2472, MD95-2043), open ocean (LR04) and Gulf of Cadiz (MD99-2339) records we have gathered new insights into the evolution of the upper MOW core on glacial-interglacial timescales. The influence of the upper MOW at Site U1386 was strongest during MIS 5 and MIS 1. Similar d18O variability can be seen in the Levantine IntermediateWater (LIW) originating from the Levantine Basin of the Eastern Mediterranean Sea. We found clear indication for a vertical shift of the MOW from the upper to the middle slope of the Gulf of Cadiz during sea level lowstands coinciding with MIS 4 and MIS 2 but also during MIS 3. Additionally, our results indicate an increased upper MOW flow correlated with Heinrich Events 7 to 10 and the Younger Dryas, and also inversely relate to precession-forced monsoonal freshwater inputs into the Eastern Mediterranean. In the context of Sapropel formation,we could not find conclusive evidence of the proposed MOW shutdown in our data.

Age control points used for the construction of the chronology at Site U1386 based on the tuning of normalized bromine (Br) (Br/total counts) at IODP Site 339-U1386 derived from XRF scanning to the planktonic G. bulloides d18O record from core MD01-2444 (Barker et al., 2011; Hodell et al., 2013).

Supplement to: Kaboth, Stefanie; Bahr, André; Reichart, Gert-Jan; Jacobs, Bram; Lourens, Lucas Joost (2016): New insights into upper MOW variability over the last 150kyr from IODP 339 Site U1386 in the Gulf of Cadiz. Marine Geology, 377, 136-145