FN Archimer Export Format
PT J
TI Time-Mean Flow as the Prevailing Contribution to the Poleward Heat Flux across the Southern Flank of the Antarctic Circumpolar Current: A Case Study in the Fawn Trough, Kerguelen Plateau
BT 
AF SEKMA, H.
   PARK, Y. -H.
   VIVIER, F.
AS 1:1;2:1;3:2;
FF 1:;2:;3:;
C1 Museum Natl Hist Nat, LOCEAN, IPSL, F-75231 Paris 05, France.
   Univ Paris 06, LOCEAN, IPSL, CNRS, Paris, France.
C2 MNHN, FRANCE
   UNIV PARIS 06, FRANCE
IF 2.871
TC 11
TU Centre national d'études spatiales
   Centre national de la recherche scientifique
   Commissariat à l'énergie atomique et aux énergies alternatives
   ELECTRICITE DE FRANCE
   Institut de recherche pour le développement
   Muséum national d'histoire naturelle
   Observatoire de Paris
   Université Paris Diderot
   Université Paris-Est Créteil Val-de-Marne
   Université Paris-Sud
   Université Pierre et Marie Curie
   Université de Cergy-Pontoise
   Université de Versailles Saint-Quentin-en-Yvelines
   École nationale des ponts et chaussées
   École normale supérieure de Paris
   École polytechnique
   École pratique des hautes études
UR https://archimer.ifremer.fr/doc/00181/29196/27591.pdf
LA English
DT Article
CR MD 172 / TRACK-1
   MD 174 / TRACK-2
BO Marion Dufresne
AB The major mechanisms of the oceanic poleward heat flux in the Southern Ocean are still in debate. The long-standing belief stipulates that the poleward heat flux across the Antarctic Circumpolar Current (ACC) is mainly due to mesoscale transient eddies and the cross-stream heat flux by time-mean flow is insignificant. This belief has recently been challenged by several numerical modeling studies, which stress the importance of mean flow for the meridional heat flux in the Southern Ocean. Here, this study analyzes moored current meter data obtained recently in the Fawn Trough, Kerguelen Plateau, to estimate the cross-stream heat flux caused by the time-mean flow and transient eddies. It is shown that the poleward eddy heat flux in this southern part of the ACC is negligible, while that from the mean flow is overwhelming by two orders of magnitude. This is due to the unusual anticlockwise turning of currents with decreasing depth, which is associated with significant bottom upwelling engendered by strong bottom currents flowing over the sloping topography of the trough. The circumpolar implications of these local observations are discussed in terms of the depth-integrated linear vorticity budget, which suggests that the six topographic features along the southern flank of the ACC equivalent to the Fawn Trough case would yield sufficient poleward heat flux to balance the oceanic heat loss in the subpolar region. As eddy activity on the southern flank of the ACC is too weak to transport sufficient heat poleward, the nonequivalent barotropic structure of the mean flow in several topographically constricted passages should accomplish the required task.
PY 2013
PD MAR
SO Journal Of Physical Oceanography
SN 0022-3670
PU Amer Meteorological Soc
VL 43
IS 3
UT 000317114800007
BP 583
EP 601
DI 10.1175/JPO-D-12-0125.1
ID 29196
ER

EF