Stable isotope record of foraminifera from the subarctic Pacific ...

• Published in: Climate Research
• Main Authors: Zahn, Rainer, Pedersen, Thomas F, Bornhold, Brian D, Mix, Alan C
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 1991
• Subjects: Piston corer; Helmholtz Centre for Ocean Research Kiel GEOMAR; Gulf of Alaska; Pacific; Pedersen; North Atlantic; Subarctic; Alaska
• Online Access: https://dx.doi.org/10.1594/pangaea.733998; https://doi.pangaea.de/10.1594/PANGAEA.733998

Benthic (Uvigerina spp., Cibicidoides spp., Gyroidinoides spp.) and planktonic (N. pachyderma sinistral, G. bulloides) stable isotope records from three core sites in the central Gulf of Alaska are used to infer mixed-layer and deepwater properties of the late glacial Subarctic Pacific. Glacial-interglacial amplitudes of the planktonic delta18O records are 1.1-1.3 per mil, less than half the amplitude observed at core sites at similar latitudes in the North Atlantic; these data imply that a strong, negative deltaw anomaly existed in the glacial Subarctic mixed layer during the summer, which points to a much stronger low-salinity anomaly than exists today. If true, the upper water column in the North Pacific would have been statically more stable than today, thus suppressing convection even more efficiently. This scenario is further supported by vertical (i.e., planktic versus benthic) delta18O and delta13C gradients of >1 per mil, which suggest that a thermohaline link between Pacific deep waters and the ... : Supplement to: Zahn, Rainer; Pedersen, Thomas F; Bornhold, Brian D; Mix, Alan C (1991): Water mass conversion in the glacial subarctic Pacific (54°N, 148°W): physical constraints and the benthic-planktonic stable isotope record. Paleoceanography, 6(5), 543-560 ...