Articles | Volume 20, issue 6
https://doi.org/10.5194/bg-20-1075-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-20-1075-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
23 Mar 2023
Research article |
| 23 Mar 2023
| 23 Mar 2023
Air–sea gas exchange in a seagrass ecosystem – results from a 3He ∕ SF6 tracer release experiment
Department of Oceanography, University of Hawai`i at Mānoa, 1000
Pope Road, Honolulu, Hawaii 96822, USA
David T. Ho
Department of Oceanography, University of Hawai`i at Mānoa, 1000
Pope Road, Honolulu, Hawaii 96822, USA
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Air-sea gas exchange regulates the Earth's climate. However, the kinetic exchange process only uses wind speed to describe, neglecting other drivers. In this study, we investigate how fetch and natural surfactants modulate the air-sea carbon dioxide exchange. Measurements from the central Baltic Sea show that limited fetch and elevated surfactants significantly suppress this exchange. A new parameterization is provided, improving regional carbon budgets and evaluations of climate solutions.
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Air-sea gas exchange regulates the Earth's climate. However, the kinetic exchange process only uses wind speed to describe, neglecting other drivers. In this study, we investigate how fetch and natural surfactants modulate the air-sea carbon dioxide exchange. Measurements from the central Baltic Sea show that limited fetch and elevated surfactants significantly suppress this exchange. A new parameterization is provided, improving regional carbon budgets and evaluations of climate solutions.
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Short summary
Seagrass meadows are productive ecosystems and bury much carbon. Understanding their role in the global carbon cycle requires knowledge of air–sea CO2 fluxes and hence the knowledge of gas transfer velocity (k). In this study, k was determined from the dual tracer technique in Florida Bay. The observed gas transfer velocity was lower than previous studies in the coastal and open oceans at the same wind speeds, most likely due to wave attenuation by seagrass and limited wind fetch in this area.
Seagrass meadows are productive ecosystems and bury much carbon. Understanding their role in the...
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