Contribution of Sea-State Dependent Bubbles to Air-Sea Carbon Dioxide Fluxes

• Published in: Geophysical Research Letters
• Main Authors: Reichil, B. G., Deike, L.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Amer Geophysical Union 2020
• Subjects: Pacific; North Atlantic
• Online Access: https://archimer.ifremer.fr/doc/00676/78838/81092.pdf; https://doi.org/10.1029/2020GL087267; https://archimer.ifremer.fr/doc/00676/78838/

Breaking surface ocean waves produce bubbles that are important for air-sea gas exchanges, particularly during high winds. In this study we estimate air-sea CO2 fluxes globally using a new approach that considers the surface wave contribution to gas fluxes. We estimate that 40% of the net air-sea CO2 flux is via bubbles, with annual, seasonal, and regional variability. When compared to traditional gas-flux parameterization methods that consider the wind speed alone, we find high-frequency (daily to weekly) differences in the predicted gas flux using the sea-state dependent method at spatial scales related to atmospheric weather (10 to 100 km). Seasonal net differences in the air-sea CO2 flux due to the sea-state dependence can exceed 20%, with the largest values associated with North Atlantic and North Pacific winter storms. These results confirm that bubbles are important for global gas-flux dynamics and that sea-state dependent parameterizations may improve performance of global coupled models.