noaa-ocean-11195 Indian Ocean Pliocene Paired Foraminiferal d18O and Mg/Ca Data Karas, C.; Nürnberg, D.; Tiedemann, R.; Garbe-Schönberg, D. Indian Ocean Pliocene Paired Foraminiferal d18O and Mg/Ca Data 2011-05-18 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/11195 Investigator C. Karas Investigator D. Nürnberg Investigator R. Tiedemann Investigator D. Garbe-Schönberg earth science paleoclimate paleoceanography delta 18O,Cibicidoides wuellerstorfi,null,per mil,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography delta 18O,Trilobatus sacculifer,null,per mil,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography magnesium/calcium,Trilobatus sacculifer,null,millimole per mole,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography age,null,null,million years ago,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography depth,null,null,meter,null,paleoceanography,null,null,N,mbsf earth science paleoclimate paleocean geochemistry earth science paleoclimate paleocean oxygen isotopes geoscientificInformation 5994000 cal yr BP 2004000 cal yr BP Complete -20.5867 -3.915 60.5517 112.2083 -3041 -1367 Ocean Indian Ocean ODP709C>LATITUDE -3.915>LONGITUDE 60.5517 Ocean Indian Ocean ODP763A>LATITUDE -20.5867>LONGITUDE 112.2083 None Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site. English DOC/NOAA/NESDIS/NCEI National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce https://www.ncdc.noaa.gov/data-access/paleoclimatology-data DATA Center Contact Bruce Bauer bruce.a.bauer@noaa.gov paleo@noaa.gov 303-497-6280 303-497-6513

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Boulder CO 80305-3328 USA online ASCII Cyrus Karas, Dirk Nürnberg, Ralf Tiedemann, Dieter Garbe-Schönberg 2011 Paleoceanography 26 2 10.1029/2010PA001949 https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2010PA001949

To understand the gradual global cooling during the mid‐Pliocene (3.5-2.5 Myr ago) one needs to consider the tectonical constriction of tropical seaways, which affected ocean circulation and the evolution of climate. Here we use paired measurements of d18O and Mg/Ca ratios of planktonic foraminifera to reconstruct the Pliocene hydrography of the western tropical Indian Ocean (Site 709C) and changes in the Leeuwin Current in the eastern subtropical Indian Ocean (Site 763A) in response to Indonesian Gateway dynamics. Today, the Indonesian Throughflow (ITF) and, subsequently, the warm southward flowing Leeuwin Current off Western Australia are essential for the polar heat transport in the Indian Ocean. During 3.5-3 Ma, sea surface temperatures significantly dropped in the Leeuwin Current area, becoming since -3.3 Ma 2C-3C cooler than the rather unchanged sea surface temperatures from the eastern and western tropical Indian Ocean. We refer this drop in sea surface temperatures to a weakened Leeuwin Current with severe climatic effects on Western Australia induced by a tectonically reduced surface ITF. We suggest that this reduced surface ITF led to a diminished poleward heat transport in the Indian Ocean resulting in a weakened Leeuwin Current and possibly to cooling of the Benguela upwelling system. STUDY NOTES: Combined planktonic foraminiferal Mg/Ca and d18O data spanning the time period from 6-2 Ma, from 2 Indian Ocean ODP sites. Core ODP 763A is located in the subtropical eastern Indian Ocean within the present influence of the Leeuwin Current, and Core ODP 709C is located in the tropical western Indian Ocean. The ODP 709C isotope data are from Shackleton and Hall, 1990.

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/karas2011/karas2011.txt GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/karas2011/karas2011.xls USA/NOAA DIF Version 9.8.4 2018-12-11 2018-12-11