Keerthi M. G. auteur aut IRD Lengaigne Matthieu auteur aut IRD Drushka K. auteur aut IRD Vialard Jérôme auteur aut IRD Montegut C. D. auteur aut IRD Pous S. auteur aut IRD Levy M. auteur aut IRD Muraleedharan P. M. auteur aut IRD text journalArticle eng text/pdf born digital access In this paper, we use an observational dataset built from Argo in situ profiles to describe the main large-scale patterns of intraseasonal mixed layer depth (MLD) variations in the Indian Ocean. An eddy permitting (0.25A degrees) regional ocean model that generally agrees well with those observed estimates is then used to investigate the mechanisms that drive MLD intraseasonal variations and to assess their potential impact on the related SST response. During summer, intraseasonal MLD variations in the Bay of Bengal and eastern equatorial Indian Ocean primarily respond to active/break convective phases of the summer monsoon. In the southern Arabian Sea, summer MLD variations are largely driven by seemingly-independent intraseasonal fluctuations of the Findlater jet intensity. During winter, the Madden-Julian Oscillation drives most of the intraseasonal MLD variability in the eastern equatorial Indian Ocean. Large winter MLD signals in northern Arabian Sea can, on the other hand, be related to advection of continental temperature anomalies from the northern end of the basin. In all the aforementioned regions, peak-to-peak MLD variations usually reach 10 m, but can exceed 20 m for the largest events. Buoyancy flux and wind stirring contribute to intraseasonal MLD fluctuations in roughly equal proportions, except for the Northern Arabian Sea in winter, where buoyancy fluxes dominate. A simple slab ocean analysis finally suggests that the impact of these MLD fluctuations on intraseasonal sea surface temperature variability is probably rather weak, because of the compensating effects of thermal capacity and sunlight penetration: a thin mixed-layer is more efficiently warmed at the surface by heat fluxes but loses more solar flux through its lower base. specialized OCEAN INDIEN ZONE TROPICALE 032 46 7-8 2633-2655 2016 0930-7575 https://www.documentation.ird.fr/hor/fdi:010066758 10.1007/s00382-015-2721-z 0930-7575 [F B010066758] https://www.documentation.ird.fr/hor/fdi:010066758 https://www.documentation.ird.fr/intranet/publi/2016/05/010066758.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2016-06-02 2017-08-23 fdi:010066758 fre