Physical Oceanography in the tropical Atlantic oxygen minimum zone ...

• Main Authors: Fischer, Tim, Banyte, Donata, Brandt, Peter, Dengler, Marcus, Krahmann, Gerd, Tanhua, Toste, Visbeck, Martin
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2013
• Subjects: Climate - Biogeochemistry Interactions in the Tropical Ocean SFB754; Gerd; Tanhua; North Atlantic
• Online Access: https://dx.doi.org/10.1594/pangaea.819311; https://doi.pangaea.de/10.1594/PANGAEA.819311

The replenishment of consumed oxygen in the open ocean oxygen minimum zone (OMZ) off northwest Africa is accomplished by oxygen transport across and along density surfaces, i.e. diapycnal and isopycnal oxygen supply. Here the diapycnal oxygen supply is investigated using a large observational set of oxygen profiles and diapycnal mixing data from years 2008 to 2010. Diapycnal mixing is inferred from different sources: (i) a large-scale tracer release experiment, (ii) microstructure profiles, and (iii) shipboard?acoustic current measurements plus density profiles. From these measurements, the average diapycnal diffusivity in the studied depth interval from 150 to 500m is estimated to be 1×10**-5 m2 s**-1, with lower and upper 95% confidence limits of 0.8×10**-5 m2 s**-1 and 1.4×10**-5 m2 s**-1. Diapycnal diffusivity in this depth range is predominantly caused by turbulence, and shows no significant vertical gradient. Diapycnal mixing is found to contribute substantially to the oxygen supply of the OMZ. Within ... : Supplement to: Fischer, Tim; Banyte, Donata; Brandt, Peter; Dengler, Marcus; Krahmann, Gerd; Tanhua, Toste; Visbeck, Martin (2013): Diapycnal oxygen supply to the tropical North Atlantic oxygen minimum zone. Biogeosciences, 10(7), 5079-5093 ...