| Title | Mid-depth South Atlantic Ocean circulation and chemical stratification during MIS-10 to 12; implications for atmospheric CO2 |
| Author | Dickson, A.J.; Leng, M.J.; Maslin, M.A. |
| Author Affil | Dickson, A.J., University College London, Department of Geography, London, United Kingdom. Other: British Geological Survey, United Kingdom; University of Nottingham, United Kingdom |
| Source | Climate of the Past, 4(4), p.333-344, . Publisher: Copernicus, Katlenburg-Lindau, International. ISSN: 1814- 9324 |
| Publication Date | 2008 |
| Notes | In English. Part of special issue No.14, Marine isotope stage 11, edited by Tzedakis, C., McManus, J. and Wolff, E., http://www.clim- past.net/special_issue14.html; published in Climate of the Past Discussion: 5 June 2008, http://www.clim-past- discuss.net/4/667/2008/cpd-4-667-2008.html; accessed in November, 2009. 53 refs. GeoRef Acc. No: 297359. CRREL Acc. No: 64002370 |
| Index Terms | carbon isotopes; isotopes; oxygen; paleoclimatology; Pleistocene; Atlantic Ocean- -Bermuda Rise; Atlantic Ocean--Cape Basin; Antarctica--Dome C; Atlantic Ocean--Labrador Sea; Norwegian Sea; Ocean Drilling Program-- ODP Site 1063; Ocean Drilling Program--ODP Site 1085; Ocean Drilling Program--ODP Site 1089; Ocean Drilling Program--ODP Site 980; Atlantic Ocean--Rockall Bank; Southern Ocean; Antarctica; Arctic Ocean; assemblages; Atlantic Ocean; benthic taxa; Bermuda Rise; C- 13/C-12; Cape Basin; carbon; carbon dioxide; Cenozoic; cores; deep-water environment; Dome C; EPICA; Foraminifera; glacial environment; interglacial environment; Invertebrata; isotope ratios; Labrador Sea; last glacial maximum; Leg 162; Leg 172; Leg 175; Leg 177; microfossils; middle Pleistocene; MIS 11; MIS- 10; MIS-12; North Atlantic; North Atlantic Deep Water; O-18/O-16; Ocean Drilling Program; ODP Site 1063; ODP Site 1085; ODP Site 1089; ODP Site 980; paleo-oceanography; paleocirculation; paleotemperature; Protista; Quaternary; Rockall Bank; South Atlantic; stable isotopes; Wilkes Land |
| Abstract | A detailed record of benthic foraminifera carbon isotopes from the intermediate-depth South East Atlantic margin shows little glacial-interglacial variability between MIS- 12 to MIS-10, suggesting that Northern Atlantic deepwaters consistently penetrated to at least 30° S. Millennial-scale increases in either the mass or flux of northern- sourced deepwaters over the core site occurred alongside reductions in Lower North Atlantic Deep Water recorded in North Atlantic sediment cores and show that the lower and intermediate limb of the Atlantic deepwater convective cell oscillated in anti- phase during previous glacial periods. In addition, a 500 yr resolution record of the Cape Basin intermediate-deep delta 13C gradient shows that a reduction in deep Southern Ocean ventilation at the end of MIS- 11 was consistent with a modelled CO2 drawdown of ~21-30 ppm. Further increases in the Southern Ocean chemical divide during the transition into MIS-10 were completed before minimum CO2 levels were reached, suggesting that other mechanisms such as alkalinity changes were responsible for the remaining ~45 ppm drawdown. |
| URL | http://www.clim-past.net/4/333/2008/cp-4-333-2008.pdf |
| Publication Type | journal article |
| Record ID | 87511 |