FN Archimer Export Format PT J TI Extratropical sources of equatorial Pacific upwelling in an OGCM BT AF RODGERS, KB BLANKE, Bruno MADEC, G AUMONT, O CIAIS, P DUTAY, JC AS 1:;2:;3:;4:;5:;6:; FF 1:;2:;3:;4:;5:;6:; C1 IPSI, LSCE, F-91191 Gif Sur Yvette, France. UBO, IFREMER, CNRS, Lab Phys Oceans, Brest, France. Univ Paris 06, IRD, CNRS, LODYC, F-75252 Paris 05, France. C2 IPSI, FRANCE UNIV BRETAGNE OCCIDENTALE, FRANCE UNIV PARIS 06, FRANCE SI UBO SE PDG-DRO-UMLPO IN WOS Ifremer jusqu'en 2018 copubli-univ-france IF 2.422 TC 69 UR https://archimer.ifremer.fr/doc/00000/10613/9403.pdf LA English DT Article AB The extratropical sources of equatorial undercurrent (EUC) water have been identified for an ocean circulation model using Lagrangian trajectory analysis. It has been found that the EUC waters emenate from a wide range of latitudes in the Pacific basin, with its densest constituent watermass being Subantarctic Mode Water (SAMW) from 50degreesS. Further analysis of the basin-scale circulation fields has revealed significant advective diapycnal mass fluxes associated with intergyre exchange. As a result of these diapycnal mass fluxes, the EUC transport as a function of density at 151degreesW (an Eulerian diagnostic) looks quite different from the original subduction rate as a function of density for the same collection of water particles. This implicates diapycnal vertical mixing as an important player in determining the preferred density horizon of maximum EUC transport along the equator. In summary, these results illustrate an important interdependence between advective and diapycnal mixing processes associated with basin-scale inter-gyre and inter-basin exchange in determining the mean equatorial stratification and EUC structure. PY 2003 SO Geophysical Research Letters SN 0094-8276 PU Amer Geophysical Union VL 30 IS 2 UT 000182892800004 DI 10.1029/2002GL016003 ID 10613 ER EF