@article{fdi:010049930,
  title = {{A}nnual reversal of the {E}quatorial intermediate current in the {P}acific : observations and model diagnostics},
  author = {{M}arin, {F}. and {K}estenare, {E}lodie and {D}elcroix, {T}hierry and {D}urand, {F}abien and {C}ravatte, {S}ophie and {E}ldin, {G}{\'e}rard and {B}ourdalle-{B}adie, {R}.},
  editor = {},
  language = {{ENG}},
  abstract = {{A} large reversal of zonal transport below the thermocline was observed over a period of 6 months in the western {P}acific {O}cean between 2 degrees {S} and the equator [from 26.2 {S}v (1 {S}v equivalent to 10(6) m(3) s(-1)) eastward in {O}ctober 1999 to 28.6 {S}v westward in {A}pril 2000]. {T}o document this reversal and assess its origin, an unprecedented collection of {ADCP} observations of zonal currents (2004-06), together with a realistic {OGCM} simulation of the tropical {P}acific, was analyzed. {T}he results of this study indicate that this reversal is the signature of intense annual variability in the subsurface zonal circulation at the equator, at the level of the {E}quatorial {I}ntermediate {C}urrent ({EIC}) and the {L}ower {E}quatorial {I}ntermediate {C}urrent ({L}-{EIC}). {I}n this study, the {EIC} and the {L}-{EIC} are both shown to reverse seasonally to eastward currents in boreal spring (and winter for the {L}-{EIC}) over a large depth range extending from 300 m to at least 1200 m. {T}he peak-to-peak amplitude of the annual cycle of subthermocline zonal currents at 165 degrees {E} in the model is similar to 30 cm s(-1) at the depth of the {EIC}, and similar to 20 cm s(-1) at the depth of the {L}-{EIC}, corresponding to a mass transport change as large as similar to 100 {S}v for the annual cycle of near-equatorial zonal transport integrated between 2 degrees {S} and 2 degrees {N} and between 410-and 1340-m depths. {Z}onal circulations on both sides of the equator (roughly within 2 degrees and 5.5 degrees in latitude) partially compensate for the large transport variability. {T}he main characteristics of the annual variability of middepth modeled currents and subsurface temperature (e. g., zonal and vertical phase velocities, meridional structure) are consistent, in the {OGCM} simulation, with the presence, beneath the thermocline, of a vertically propagating equatorial {R}ossby wave forced by the westward-propagating component of the annual equatorial zonal wind stress. {I}nterannual modulation of the annual variability in subthermocline equatorial transport is discussed.},
  keywords = {{PACIFIQUE}},
  booktitle = {},
  journal = {{J}ournal of {P}hysical {O}ceanography},
  volume = {40},
  numero = {5},
  pages = {915--933},
  ISSN = {0022-3670},
  year = {2010},
  DOI = {10.1175/2009jpo4318.1},
  URL = {https://www.documentation.ird.fr/hor/fdi:010049930},
}