FN Archimer Export Format
PT J
TI The exchange of Intermediate Water in the southeast Atlantic: Water mass transformations diagnosed from the Lagrangian analysis of a regional ocean model
BT 
AF RIMAUD, Julie
   SPEICH, Sabrina
   BLANKE, Bruno
   GRIMA, Nicolas
AS 1:2;2:2;3:1,2;4:1,2;
FF 1:;2:;3:;4:;
C1 CNRS Ifremer IRD UBO, UMR 6523, Lab Phys Oceans, FR-29238 Brest 3, France.
C2 CNRS, FRANCE
   UBO, FRANCE
IF 3.17
TC 15
TU Centre national de la recherche scientifique
   Institut de recherche pour le développement
   Institut français de recherche pour l'exploitation de la mer
   Université de Bretagne Occidentale
UR https://archimer.ifremer.fr/doc/00098/20921/18532.pdf
LA English
DT Article
CR MD 166 / BONUS-GOODHOPE
BO Marion Dufresne
AB Results from a regional ocean model and numerical Lagrangian analyses are compared with in situ measurements to describe the properties and dynamics of Antarctic Intermediate Water (AAIW) in the region of the Cape Basin. The AAIW that originates in the South Atlantic (A-AAIW) at 8 degrees W follows two branches. A southern branch, flowing mostly south of 40 degrees S, is blocked by topography and is deflected westward without significant changes in its physical properties. A northern branch crosses the Cape Basin with strong modification of its physical properties. The AAIW that originates in the Indian Ocean (I-AAIW) flows into the Atlantic Ocean via the Agulhas Current and undergoes small physical changes in the Cape Basin. In the model, the salinity ranges of A-AAIW and I-AAIW cores that reach the southeast Atlantic are 34.2-34.5 and 34.5-34.6, respectively. The modeled AAIW distribution and behavior compare well with observations, despite a bias of +0.2 in salinity. To investigate the dynamical processes involved in the interocean exchanges of these AAIW varieties, we use diagnoses based on the Okubo-Weiss parameter and the directional variations of trajectories of particles transported by the model velocity field. Our results suggest that I-AAIW flows into the Cape Basin more within eddies, and particularly within cyclones, than A-AAIW. Once the mixing of both varieties operates, physical and behavioral differences fade and the resulting AAIW flows over the Walvis Ridge in a less turbulent way as part of the Benguela Current, with salinity between 34.55 and 34.6.
PY 2012
PD AUG
SO Journal Of Geophysical Research-oceans
SN 0148-0227
PU Amer Geophysical Union
VL 117
IS C08034
UT 000308027200005
DI 10.1029/2012JC008059
ID 20921
ER

EF