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Influence of northwest Pacific productivity on North Pacific Intermediate Water oxygen concentrations during the Bølling-Ållerød interval (14.7-12.9 ka)

John Crusius·Thomas F. Pedersen·Stephanie Kienast·Lloyd D. Keigwin·Laurent Labeyrie
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Abstract

Elevated productivity in the northwest Pacific is suggested as a new possible control driving past intervals of low-O 2 intermediate water along the western continental margin of North America. According to this mechanism, O 2 consumption would occur near the site of formation of North Pacific Intermediate Water (NPIW), due to increased respiration of organic carbon in response to a high-productivity event. Evidence is provided for such a productivity increase during the Bølling-Ållerød interval (14.7–12.9 ka), a time when laminated sediments were deposited along the northern California margin. By this mechanism, low-O 2 events in intermediate waters off the western North American margin could occur without significant changes in the rate of NPIW ventilation.

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John Crusius, Thomas F. Pedersen, Stephanie Kienast, Lloyd D. Keigwin, Laurent Labeyrie. 2004. Influence of northwest Pacific productivity on North Pacific Intermediate Water oxygen concentrations during the Bølling-Ållerød interval (14.7-12.9 ka). https://doi.org/10.1130/g20508.1

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