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Satellite Observations of Imprint of Oceanic Current on Wind Stress by Air-Sea Coupling.

ABSTRACT: Mesoscale eddies are present everywhere in the ocean and partly determine the mean state of the circulation and ecosystem. The current feedback on the surface wind stress modulates the air-sea transfer of momentum by providing a sink of mesoscale eddy energy as an atmospheric source. Using nine years of satellite measurements of surface stress and geostrophic currents over the global ocean, we confirm that the current-induced surface stress curl is linearly related to the current vorticity. The resulting coupling coefficient between current and surface stress (s? [N s m-3]) is heterogeneous and can be roughly expressed as a linear function of the mean surface wind. s? expresses the sink of eddy energy induced by the current feedback. This has important implications for air-sea interaction and implies that oceanic mean and mesoscale circulations and their effects on surface-layer ventilation and carbon uptake are better represented in oceanic models that include this feedback.

SUBMITTER: Renault L

PROVIDER: S-EPMC5735162 | biostudies-other | 2017 Dec

REPOSITORIES: biostudies-other

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Satellite Observations of Imprint of Oceanic Current on Wind Stress by Air-Sea Coupling.

Renault Lionel L McWilliams James C JC Masson Sebastien S

Scientific reports 20171218 1

Mesoscale eddies are present everywhere in the ocean and partly determine the mean state of the circulation and ecosystem. The current feedback on the surface wind stress modulates the air-sea transfer of momentum by providing a sink of mesoscale eddy energy as an atmospheric source. Using nine years of satellite measurements of surface stress and geostrophic currents over the global ocean, we confirm that the current-induced surface stress curl is linearly related to the current vorticity. The ...[more]

PMID: 29255277

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