Evidence for enhanced convection of North Pacific Intermediate Water to the low-latitude Pacific under glacial conditions

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doi: 10.1002/2016PA002994
Author(s): Max, Lars; Rippert, N.; Lembke-Jene, L.; Mackensen, A.; Nürnberg, D.; Tiedemann, R.
Author Affiliation(s): Primary:
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
Helmholtz Centre for Ocean Research Kiel, Germany
Volume Title: Paleoceanography
Source: Paleoceanography, 32(1), p.41-55. Publisher: American Geophysical Union, Washington, DC, United States. ISSN: 0883-8305 CODEN: POCGEP
Note: In English. 81 refs.; illus., incl. sketch map
Summary: We provide high-resolution foraminiferal stable carbon isotope (δ13C) records from the subarctic Pacific and Eastern Equatorial Pacific (EEP) to investigate circulation dynamics between the extratropical and tropical North Pacific during the past 60 kyr. We measured the δ13C composition of the epibenthic foraminiferal species Cibicides lobatulus from a shallow sediment core recovered from the western Bering Sea (SO201-2-101KL; 58°52.52'N, 170°41.45'E; 630 m water depth) to reconstruct past ventilation changes close to the source region of Glacial North Pacific Intermediate Water (GNPIW). Information regarding glacial changes in the δ13C of subthermocline water masses in the EEP is derived from the deep-dwelling planktonic foraminifera Globorotaloides hexagonus at ODP Site 1240 (00°01.31'N, 82°27.76'W; 2921 m water depth). Apparent similarities in the long-term evolution of δ13C between GNPIW, intermediate waters in the eastern tropical North Pacific and subthermocline water masses in the EEP suggest the expansion of relatively 13C-depleted, nutrient-enriched, and northern sourced intermediate waters to the equatorial Pacific under glacial conditions. Further, it appears that additional influence of GNPIW to the tropical Pacific is consistent with changes in nutrient distribution and biological productivity in surface waters of the glacial EEP. Our findings highlight potential links between North Pacific mid-depth circulation changes, nutrient cycling, and biological productivity in the equatorial Pacific under glacial boundary conditions. Abstract Copyright (2016) American Geophysical Union. All Rights Reserved.
Year of Publication: 2017
Research Program: ODP Ocean Drilling Program
Key Words: 02 Geochemistry; 24 Surficial Geology, Quaternary Geology; Bering Sea; C-13/C-12; Carbon; Cenozoic; Cibicides; Cibicides lobatulus; East Pacific; Equatorial Pacific; Foraminifera; Glaciation; Globorotaloides; Globorotaloides hexagonus; Holocene; Invertebrata; Isotope ratios; Isotopes; Leg 202; Marine environment; Microfossils; North Pacific; North Pacific Intermediate Water; O-18/O-16; ODP Site 1240; Ocean Drilling Program; Orbitoidacea; Oxygen; Pacific Ocean; Paleo-oceanography; Paleoclimatology; Paleoenvironment; Panama Basin; Pleistocene; Protista; Quaternary; Rotaliina; Stable isotopes; Upper Pleistocene
Coordinates: N000100 N000100 W0822800 W0822800
N585300 N585300 E1704200 E1704200
Record ID: 2017020820
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from John Wiley & Sons, Chichester, United Kingdom