- Impacts of mesoscale activity on the water masses and circulation in the Coral Sea doi link

Auteur(s): Rousselet L., Doglioli A., Maes Christophe, Blanke Bruno, Petrenko A.

(Article) Publié: Journal Of Geophysical Research. Oceans, vol. p. (2016)

Ref HAL: hal-01393475_v1
DOI: 10.1002/2016JC011861
Exporter : BibTex | endNote

The climatological vision of the circulation within the Coral Sea is today well established withthe westward circulation of two main jets, the North Caledonian Jet (NCJ) and the North Vanuatu Jet (NVJ)as a consequence of the separation of the South Equatorial Current (SEC) on the islands of New Caledonia,Vanuatu, and Fiji. Each jet has its own dynamic and transports different water masses across the Coral Sea.The influence of mesoscale activity on mean flow and on water mass exchanges is not yet fully explored inthis region of intense activity. Our study relies on the analysis of in situ, satellite, and numerical data. Indeed,we first use in situ data from the Bifurcation cruise and from an Argo float, jointly with satellite-derivedvelocities, to study the eddy influence on the Coral Sea dynamics. We identify an anticyclonic eddy asparticipating in the transport of NVJ-like water masses into the theoretical pathway of NCJ waters. Thistransfer from the NVJ to the NCJ is confirmed over the long term by a Lagrangian analysis. In particular, thisnumerical analysis shows that anticyclonic eddies can contribute up to 70–90% of the overall eddy transferbetween those seemingly independent jets. Finally, transports calculated using S-ADCP measurements(0–500 m) show an eddy-induced sensitivity that can reach up to 15 Sv, i.e., the order of the transport of thejets.