Publications des scientifiques de l'IRD

Jullien S., Masson S., Oerder V., Samson G., Colas François, Renault Lionel. (2020). Impact of ocean-atmosphere current feedback on ocean mesoscale activity : regional variations and sensitivity to model resolution. Journal of Climate, 33 (7), p. 2585-2602. ISSN 0894-8755.

Titre du document
Impact of ocean-atmosphere current feedback on ocean mesoscale activity : regional variations and sensitivity to model resolution
Année de publication
2020
Type de document
Article référencé dans le Web of Science WOS:000517554400001
Auteurs
Jullien S., Masson S., Oerder V., Samson G., Colas François, Renault Lionel
Source
Journal of Climate, 2020, 33 (7), p. 2585-2602 ISSN 0894-8755
Ocean mesoscale eddies are characterized by rotating-like and meandering currents that imprint the low-level atmosphere. Such a current feedback (CFB) has been shown to induce a sink of energy from the ocean to the atmosphere, and consequently to damp the eddy kinetic energy (EKE), with an apparent regional disparity. In a context of increasing model resolution, the importance of this feedback and its dependence on oceanic and atmospheric model resolution arise. Using a hierarchy of quasi-global coupled models with spatial resolutions varying from 1/4 degrees to 1/12 degrees, the present study shows that the CFB induces a negative wind work at scales ranging from 100 to 1000 km, and a subsequent damping of the mesoscale activity by 30% on average, independently of the model resolution. Regional variations of this damping range from 20% in very rich eddying regions to 40% in poor eddying regions. This regional modulation is associated with a different balance between the sink of energy by eddy wind work and the source of EKE by ocean intrinsic instabilities. The efficiency of the CFB is also shown to be a function of the surface wind magnitude: the larger the wind, the larger the sink of energy. The CFB impact is thus related to both wind and EKE. Its correct representation requires both an ocean model that resolves the mesoscale field adequately and an atmospheric model resolution that matches the ocean effective resolution and allows a realistic representation of wind patterns. These results are crucial for including adequately mesoscale ocean-atmosphere interactions in coupled general circulation models and have strong implications in climate research.
Plan de classement
Sciences fondamentales / Techniques d'analyse et de recherche [020] ; Sciences du milieu [021] ; Limnologie physique / Océanographie physique [032]
Localisation
Fonds IRD [F B010078009]
Identifiant IRD
fdi:010078009
Contact