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Title: Air‐Sea Gas Transfer: Determining Bubble Fluxes With In Situ N 2 Observations
Abstract

Oxygen measurements by in situ sensors on remote platforms are used to determine net biological oxygen fluxes in the surface ocean. On an annual basis these fluxes are stoichiometrically related to the export of organic carbon from the upper ocean (the ocean's biological carbon pump). In situ measurements on remote platforms make it feasible to observe the annual biological oxygen flux globally, but the accuracy of these estimates during periods of high winds depends on model‐determined fluxes by bubble processes created by breaking waves. We verify the importance of bubble processes in the gas exchange model of Liang et al. (2013,https://doi.org/10.1002gbc.20080) using surface‐ocean N2gas measurements determined from observations of dissolved gas pressure and oxygen concentrations every 3 hr on a mooring in the northeast subarctic Pacific at Ocean Station Papa. The changes in N2concentration during 10 separate monthlong periods in the winters between 2007 and 2016 indicate that bubble processes in the gas exchange model are over predicted by about a factor of 3 at this location. (The bubble mass transfer coefficients must be multiplied by 0.37 ± 0.14 to match the observations.) These results can be used to adjust model‐determined bubble fluxes to yield more accurate measurements of net biological oxygen production until the next generation gas‐exchange models are developed.

 
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NSF-PAR ID:
10461289
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Journal of Geophysical Research: Oceans
Volume:
124
Issue:
4
ISSN:
2169-9275
Page Range / eLocation ID:
p. 2716-2727
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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