FN Archimer Export Format
PT J
TI A PV-approach for dense water formation along fronts: Application to the Northwestern Mediterranean
BT 
AF GIORDANI, Herve
   LEBEAUPIN-BROSSIER, Cindy
   LEGER, Fabien
   CANIAUX, Guy
AS 1:1;2:1;3:1;4:1;
FF 1:;2:;3:;4:;
C1 Meteo France, CNRS, UMR 3589, Ctr Natl Rech Meteorol CNRM GAME, Toulouse 01, France.
C2 CNRM (METEO FRANCE), FRANCE
IF 2.711
TC 14
UR https://archimer.ifremer.fr/doc/00466/57755/60023.pdf
LA English
DT Article
CR MOOSE-GE
AB The mechanisms of dense water formation (sigma > 29: 0 kgm(-3)) at work in the baroclinic cyclonic gyre of the North-Western Mediterranean basin are investigated through a PV-budget (PV: Potential Vorticity). The PV-budget is diagnosed from an eddy-resolving (1/36 degrees) ocean simulation driven in surface by hourly air-sea fluxes provided by a nonhydrostatic atmospheric model at 2: 5 km resolution. The PV-budget is controlled by the diabatic, frictional, and advective PV-fluxes. Around the gyre the surface diabatic PV-flux dominates the PV-destruction, except along the northern branch of the North Current where the surface frictional PV-flux is strongly negative. In this region, the bathymetry stabilizes the front and maintains the current northerly in the same direction as the dominant northerly wind. This configuration leads to optimal wind-current interactions and explains the preponderance of frictional PV-destruction on diabatic PVdestruction. This mechanical forcing drives a cross-front ageostrophic circulation which subducts surface low-PV waters destroyed by wind on the dense side of the front and obducts high-PV waters from the pycnocline on the light side of the front. The horizontal PV-advections associated with the geostrophic cyclonic gyre and turbulent entrainment at the pycnocline also contribute to the PV-refueling in the frontal region. The surface nonadvective PV-flux involves energy exchanges down to 21400 Wm(-2) in the frontal zone: this flux is 3.5 times stronger than atmospheric buoyancy flux. These energy exchanges quantify the coupling effects between the surface atmospheric forcing with the oceanic frontal structures at submesoscale. 
PY 2017
PD FEB
SO Journal Of Geophysical Research-oceans
SN 2169-9275
PU Amer Geophysical Union
VL 122
IS 2
UT 000398063100014
BP 995
EP 1015
DI 10.1002/2016JC012019
ID 57755
ER

EF