Scales and dynamics of Submesoscale Coherent Vortices formed by deep convection in the northwestern Mediterranean Sea
|Author(s)||Bosse Anthony1, Testor Pierre1, Houpert Loic2, Damien Pierre3, Prieur Louis4, Hayes Daniel5, Taillandier Vincent4, Durrieu De Madron Xavier6, D'Ortenzio Fabrizio4, Coppola Laurent4, Karstensen Johannes7, Mortier Laurent8|
|Affiliation(s)||1 : UPMC Univ Paris 06, Sorbonne Univ, CNRS, IRD,MNHN,IPSL,Lab Oceanog & Climatol,UMR 7159, Paris, France.
2 : Scottish Assoc Marine Sci, Oban, Argyll, Scotland.
3 : Ctr Invest Cient & Educ Super Ensenada, Dept Oceanog Fis, Ensenada, Baja California, Mexico.
4 : UPMC Univ Paris 06, Sorbonne Univ, Lab Oceanog Villefranche, Observ Oceanol,UMR 7093, Villefranche Sur Mer, France.
5 : Univ Cyprus, Oceanog Ctr, Nicosia, Cyprus.
6 : Univ Perpignan, CNRS, Ctr Rech & Format Environm Mediterraneens, Perpignan, France.
7 : Helmholtz Zentrum Ozeanforsch, GEOMAR, Kiel, Germany.
8 : ENSTA Paristech, Palaiseau, France.
|Source||Journal Of Geophysical Research-oceans (2169-9275) (Amer Geophysical Union), 2016-10 , Vol. 121 , N. 10 , P. 7716-7742|
|WOS© Times Cited||55|
|Keyword(s)||Submesoscale Coherent Vortices, deep convection, deep waters transport, Mediterranean Sea|
|Abstract||Since 2010, an intense effort in the collection of in situ observations has been carried out in the northwestern Mediterranean Sea thanks to gliders, profiling floats, regular cruises, and mooring lines. This integrated observing system enabled a year-to-year monitoring of the deep waters formation that occurred in the Gulf of Lions area during four consecutive winters (2010–2013). Vortical structures remnant of wintertime deep vertical mixing events were regularly sampled by the different observing platforms. These are Submesoscale Coherent Vortices (SCVs) characterized by a small radius (∼5–8 km), strong depth-intensified orbital velocities (∼10–20 cm s−1) with often a weak surface signature, high Rossby (∼0.5) and Burger numbers O(0.5–1). Anticyclones transport convected waters resulting from intermediate (∼300 m) to deep (∼2000 m) vertical mixing. Cyclones are characterized by a 500–1000 m thick layer of weakly stratified deep waters (or bottom waters that cascaded from the shelf of the Gulf of Lions in 2012) extending down to the bottom of the ocean at ∼2500 m. The formation of cyclonic eddies seems to be favored by bottom-reaching convection occurring during the study period or cascading events reaching the abyssal plain. We confirm the prominent role of anticyclonic SCVs and shed light on the important role of cyclonic SCVs in the spreading of a significant amount (∼30%) of the newly formed deep waters away from the winter mixing areas. Since they can survive until the following winter, they can potentially have a great impact on the mixed layer deepening through a local preconditioning effect.|