Publications des scientifiques de l'IRD

Cuypers Y., Bouruet-Aubertot P., Vialard Jérôme, McPhaden M. J. (2017). Focusing of internal tides by near-inertial waves. Geophysical Research Letters, 44 (5), p. 2398-2406. ISSN 0094-8276.

Titre du document
Focusing of internal tides by near-inertial waves
Année de publication
2017
Type de document
Article référencé dans le Web of Science WOS:000398183700040
Auteurs
Cuypers Y., Bouruet-Aubertot P., Vialard Jérôme, McPhaden M. J.
Source
Geophysical Research Letters, 2017, 44 (5), p. 2398-2406 ISSN 0094-8276
The refraction of internal waves by lower-frequency near-inertial waves has been predicted theoretically, but never observed before. Here, we report observations of semi-diurnal internal tides generated by the rough topography of the Central Indian Ridge, in the presence of a strong, lower-frequency near-inertial wave field generated by a tropical storm. The semi-diurnal internal tide energy is trapped within upward propagating bands with a periodicity close to the inertial period. A ray-tracing model suggests that this trapping results from the internal tide refraction by the shear associated with near-inertial waves. This yields a strong increase of the internal tide energy and shear in space-time regions where the background flow focuses the rays, leading to the formation of caustics. This mechanism may increase vertical mixing generated by baroclinic tides in the vicinity of mid-ocean ridges in tropical regions.
Plan de classement
Limnologie physique / Océanographie physique [032]
Description Géographique
OCEAN INDIEN ; ZONE TROPICALE
Localisation
Fonds IRD [F B010069421]
Identifiant IRD
fdi:010069421
Contact