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Abstract Wave breaking induced bubbles contribute a significant part of air‐sea gas fluxes. Recent modeling of the sea state dependent CO2flux found that bubbles contribute up to ∼40% of the total CO2air‐sea fluxes (Reichl & Deike, 2020,https://doi.org/10.1029/2020gl087267). In this study, we implement the sea state dependent bubble gas transfer formulation of Deike and Melville (2018,https://doi.org/10.1029/2018gl078758) into a spectral wave model (WAVEWATCH III) incorporating the spectral modeling of the wave breaking distribution from Romero (2019,https://doi.org/10.1029/2019gl083408). We evaluate the accuracy of the sea state dependent gas transfer parameterization against available measurements of CO2gas transfer velocity from 9 data sets (11 research cruises, see Yang et al. (2022,https://doi.org/10.3389/fmars.2022.826421)). The sea state dependent parameterization for CO2gas transfer velocity is consistent with observations, while the traditional wind‐only parameterization used in most global models slightly underestimates the observations of gas transfer velocity. We produce a climatology of the sea state dependent gas transfer velocity using reanalysis wind and wave data spanning 1980–2017. The climatology shows that the enhanced gas transfer velocity occurs frequently in regions with developed sea states (with strong wave breaking and high significant wave height). The present study provides a general sea state dependent parameterization for gas transfer, which can be implemented in global coupled models.
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Modulation of Bubble‐Mediated CO 2 Gas Transfer Due To Wave‐Current Interactions
Abstract Wave breaking modulates air‐sea fluxes of energy, momentum, heat, and gases. Building on recent advances in the modeling of CO2gas exchange and wave breaking, we investigate the variability of bubble‐mediated gas transfer coefficients due to wave‐current interactions. Submesoscale current gradients strongly modulate wave breaking, which can enhance the bubble‐mediated gas transfer coefficient along temperature fronts and cold filaments. The enhancement of the gas transfer coefficient is over relatively small areas averaging out over larger regions. However, the correlation between positively anomalous gas transfer coefficients and regions with strong downwelling could potentially enhance CO2exchange over regions with increased submesoscale activity. An empirical scaling based on the mean wave period, root‐mean‐square current gradients, and friction velocity can explain the root‐mean‐square differences of gas transfer coefficients computed from solutions with and without current forcing.
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- PAR ID:
- 10380918
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 49
- Issue:
- 22
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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