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International Ocean Discovery Program Expedition 361 Preliminary Report South African Climates (Agulhas LGM Density Profile)

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International Ocean Discovery Program Expedition 361 Preliminary Report South African Climates (Agulhas LGM Density Profile) International Ocean Discovery Program Expedition 361 Preliminary Report South African Climates (Agulhas LGM Density Profile) 30 January–31 March 2016 Ian R. Hall, Sidney R. Hemming, Leah J. LeVay, and the Expedition 361 Scientists Publisher’s notes Core samples and the wider set of data from the science program covered in this report are under moratorium and accessible only to Science Party members until 30 September 2017. This publication was prepared by the JOIDES Resolution Science Operator (JRSO) at Texas A&M University (TAMU) as an account of work performed under the International Ocean Discovery Pro- gram (IODP). Funding for IODP is provided by the following international partners: National Science Foundation (NSF), United States Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan European Consortium for Ocean Research Drilling (ECORD) Ministry of Science and Technology (MOST), People’s Republic of China Korea Institute of Geoscience and Mineral Resources (KIGAM) Australia-New Zealand IODP Consortium (ANZIC) Ministry of Earth Sciences (MoES), India Coordination for Improvement of Higher Education Personnel, Brazil (CAPES) Portions of this work may have been published in whole or in part in other International Ocean Discovery Program documents or publications. Disclaimer Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the participating agencies, TAMU, or Texas A&M Research Foundation. Copyright Except where otherwise noted, this work is licensed under a Creative Commons Attribution License. Unrestricted use, distribution, and reproduction is permitted, provided the original author and source are credited. Citation Hall, I.R., Hemming, S.R., LeVay, L.J., and the Expedition 361 Scientists, 2016. Expedition 361 Preliminary Report: South African Climates (Agulhas LGM Density Profile). International Ocean Discovery Program. http://dx.doi.org/10.14379/iodp.pr.361.2016 ISSN World Wide Web: 2372-9562 May 2016 I.R. Hall et al. Expedition 361 Preliminary Report Expedition 361 Scientific Participants Expedition 361 scientists Ian R. Hall Thibaut Caley Jens Gruetzner Co-Chief Scientist Sedimentologist Physical Properties Specialist/Logging Department of Earth Sciences EPOC, UMR CNRS 5805 Scientist Cardiff University University of Bordeaux Geosciences Main College, Park Place, PO Box 914 Allee Geoffroy saint Hilaire Alfred-Wegener-Institut for Polar and Cardiff Wales CF10 3AT 33615 Pessac Marine Research United Kingdom France Am Alten Hafen 26 [email protected] [email protected] 27568 Bremenhaven Germany Sidney R. Hemming Alejandra Cartagena-Sierra [email protected] Co-Chief Scientist Sedimentologist Lamont-Doherty Earth Observatory Department of Civil Engineering & Xibin Han Columbia University Geological Sciences Sedimentologist 61 Route 9W University of Notre Dame Second Institute of Oceanography Palisades NY 10964 125 Fitzpatrick Hall (SOA) USA Notre Dame IN 46556 Key Laboratory of Submarine Science [email protected] USA 36 Baochubeilu [email protected] Hangzhou City Leah J. LeVay China Expedition Project Manager/Staff Scien- Christopher D. Charles [email protected] tist Stratigraphic Correlator International Ocean Discovery Pro- Scripps Institution of Oceanography Sophia K.V. Hines gram University of California, San Diego Inorganic Geochemist Texas A&M University La Jolla CA 92093-0220 Division of Geological and Planetary 1000 Discovery Drive USA Sciences College Station TX 77845 [email protected] California Institute of Technology USA 1200 East California Boulevard, MC Jason J. Coenen [email protected] 131-24 Paleontologist (diatoms) Pasadena CA 91125 Stephen R. Barker Department of Geology USA Stratigraphic Correlator Northern Illinois University [email protected] School of Earth and Ocean Sciences 235 North Sacramento Street, Unit F Cardiff University Sycamore IL 60178 Francisco J. Jimenez Espejo Main Building, Park Place USA Physical Properties Specialist Cardiff Wales CF10 3AT [email protected] Institute of Biogeosciences United Kingdom Japan Agency for Marine-Earth Science Julien G. Crespin [email protected] and Technology (JAMSTEC) Sedimentologist Natsushima-cho 2-15 Melissa A. Berke EPOC, UMR CNRS 5805 Yokosuka 237-0061 Organic Geochemist University of Bordeaux Japan Department of Civil Engineering & Allee Geoffroy saint Hilaire [email protected] Geological Sciences 33615 Pessac University of Notre Dame France Janna Just 156 Fitzpatrick Hall [email protected] Paleomagnetist Notre Dame IN 46556 Geologisches Institut Allison M. Franzese USA Universität Kõln Inorganic Geochemist [email protected] Zühlpicher Strasse 49a Natural Sciences Department 50674 Cologne Luna Brentegani School of Earth and Environmental Sci- Germany Paleontologist (nannofossils) ences [email protected] Earth and Environmental Sciences Hostos Community College (CUNY) University of Technology Queensland 500 Grand Concourse Gardens Point Campus Bronx NY 10451 Brisbane QLD 4000 USA Australia [email protected] [email protected] 3 I.R. Hall et al. Expedition 361 Preliminary Report Andreas Koutsodendris Thiago Pereira dos Santos Deborah Tangunan Sedimentologist Paleontologist (planktonic foraminifers) Paleontologist (nannofossils) Institute of Earth Sciences Institute for Geosciences Department of Geosciences University of Heidelberg Universidade Federal Fluminense (UFF) University of Bremen Im Neuenheimer Feld 234 Rio de Janeiro 24020 Klagenfurterstrasse 69120 Heidelberg Brazil 28359 Bremen Germany [email protected] Germany [email protected] [email protected] Rebecca Robinson heidelberg.de Inorganic Geochemist Jeroen J.L. van der Lubbe Kaoru Kubota Graduate School of Oceanography Paleomagnetist Sedimentologist University of Rhode Island Department of Sedimentology Atmosphere and Ocean Research Insti- South Ferry Road University Amsterdam tute Narragansett RI 02882 1081 Amsterdam University of Tokyo USA Netherlands 5-1-5 Kashiwano-ha [email protected] [email protected] Kashiwashi Chiba 277-8564 John M. Rolison Masako Yamane Japan Inorganic Geochemist Sedimentologist [email protected] Chemistry Department Department of Biogeochemistry Nambiyathodi Lathika University of Otago Japan Agency for Marine-Earth Science Physical Properties Specialist PO Box 56 and Technology (JAMSTEC) Ice Core Laboratory Dunedin 9054 2-15 Natsushima-cho, Yokosuka National Centre for Antarctic and New Zealand Kanagawa 237-0061 Ocean Research (NCAOR) [email protected] Japan Head Land Sada [email protected] Margit H. Simon Vasco da Gama Goa 403804 Paleontologist (benthic foraminifers) Hucai Zhang India Uni Research Climate and Bjerknes Sedimentologist [email protected] Centre for Climate Research Lab of Plateau Lake Ecology and Global Richard D. Norris Allégaten 55 Change Paleontologist (planktonic foraminifers) 5007 Bergen Yunnan Normal University Scripps Institution of Oceanography Norway 1 Yuhua District University of California, San Diego [email protected] Kunming Chengong 650500 9500 Gilman Drive China LaJolla CA 92093-0244 [email protected] USA [email protected] Education and Outreach Nina Rooks-Cast Education/Outreach Officer Mount Pleasant High School Providence RI USA [email protected] Siem Offshore AS Officials Steve Bradley Wayne Malone Master of the Drilling Vessel Offshore Installation Manager 4 I.R. Hall et al. Expedition 361 Preliminary Report Technical Support Alexis Armstrong Timothy Fulton Michael Hodge Core Laboratory (temporary) Imaging Specialist Marine Computer Specialist Lisa Brandt Clayton Furman Jon Howell Chemistry Laboratory Logging Engineer Application Developer Timothy Bronk James Gillette Michael Meiring Assistant Laboratory Officer Marine Computer Specialist Staff Electronics Designer Chad Broyles Randy Gjesvold William Mills Curatorial Specialist Marine Instrumentation Specialist Laboratory Officer Lisa Crowder Rachael Gray Algie Morgan Assistant Laboratory Officer Chemistry Laboratory Application Developer Benjamin Daniel Kevin Grigar Beth Novak Thin Section Laboratory Operations Superintendent Paleomagnetism Laboratory Keith Dupuis Margaret Hastedt Lars Thorsen Publications Specialist Physical Properties Laboratory Core Laboratory (temporary) Seth Frank Sandra Herrmann Garrick Van Rensburg X-ray Laboratory Core Laboratory Marine Instrumentation Specialist 5 I.R. Hall et al. Expedition 361 Preliminary Report Abstract water into the South Atlantic stimulates regional buoyancy anoma- lies that ultimately impact convective activity in the northern North International Ocean Discovery Program (IODP) Expedition 361 Atlantic, plausibly acting as a contributor to the basin-wide Atlantic drilled six sites on the southeast African margin and in the Indian- Meridional Overturning Circulation (AMOC) (Figure F1) (Weijer, Atlantic ocean gateway, southwest Indian Ocean, from 30 January 2000; Weijer et al., 2002; Knorr and Lohmann, 2003; Van Sebille et to 31 March 2016. In total, 5175 m of core was recovered, with an al., 2009; Biastoch et al., 2008, 2009a). The numerical simulations average recovery of 102%, during 29.7 days of on-site operations. specifically point to Agulhas leakage as a potential modulator of the The sites, situated in the Mozambique Channel at locations directly AMOC and a rheostat for the ventilation of the deep ocean. Hence influenced by discharge from the Zambezi and Limpopo River the significance of
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