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| Titel |
A simple mixing explanation for late Pleistocene changes in the Pacific-South Atlantic benthic δ13C gradient |
| VerfasserIn |
L. E. Lisiecki |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1814-9324
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| Digitales Dokument |
URL |
| Erschienen |
In: Climate of the Past ; 6, no. 3 ; Nr. 6, no. 3 (2010-05-07), S.305-314 |
| Datensatznummer |
250003544
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| Publikation (Nr.) |
 copernicus.org/cp-6-305-2010.pdf |
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| Zusammenfassung |
| The fact that the deep-ocean benthic δ13C minimum shifted from the
North Pacific to the South Atlantic during the Last Glacial Maximum is often
interpretted as evidence of a change in deep water circulation, such as the
development of deep water ventilation in the North Pacific or a decrease in
Southern Ocean overturning. This study re-evaluates the implications of
changes in benthic δ13C gradients by comparing Pacific Deep Water
(PDW) δ13C measurements with the values expected for the null
hypothesis that PDW ventilation sources remained unchanged throughout the
Late Pleistocene. The δ13C compositions of PDW, Northern Component
Water (NCW) and Southern Component Water (SCW) are estimated from regional
benthic δ13C stacks of 3–6 sites. Changes in PDW δ13C
and PDW-SCW δ13C gradients over the past 800 kyr are found to be
well described by a constant mixture of 60% NCW and 40% SCW plus a constant
Pacific remineralization offset of −0.5‰. Thus, a change in
PDW ventilation cannot be inferred solely on the basis of changes in the
Pacific-South Atlantic benthic δ13C gradient. |
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