Onset of Mediterranean outflow into the North Atlantic

• Published in: Science
• Main Authors: Hernández-Molina, F. Javier, Miller, Madeline
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: American Association for the Advancement of Science 2014
• Subjects: Holloway; Tomlinson; North Atlantic
• Online Access: https://doi.org/10.1126/science.1251306

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. © 2014 American Association for the Advancement of Science. Received 24 January 2014; accepted 8 May 2014. This research used samples and data collected through the Integrated Ocean Drilling Program (IODP). The research was partially supported through the CTM 2008-06399-C04/MAR, CTM 2012-39599-C03, CGL2011-26493, CTM2012-38248, IGCP-619, INQUA 1204, and FWF P25831-N29 Projects. The Continental Margins Research Group at Royal Holloway, University of London, also contributed to the research. We thank REPSOL and TGS–NOPEC (Tomlinson Geophysical Services Inc. and Norwegian Petroleum Exploration Consultants) Geophysical Company ASA for use of an unpublished seismic record. We thank N. Khélifi (Springer, Germany) and M. Rogerson (University of Hull, UK) for discussing the changes in MOW density during the Pliocene and Quaternary, as well as the anonymous reviewers whose suggestions improved the final version of our manuscript. Data available at http://doi.pangaea.de/10.1594/ PANGAEA.832885?format=html and at the IODP web page, http:// iodp.tamu.edu/scienceops/expeditions/mediterranean_outflow.html.