@article{PAR00007715,
  title = {{B}asin resonances in the equatorial {I}ndian {O}cean},
  author = {{H}an, {W}. {Q}. and {M}c{C}reary, {J}. {P}. and {M}asumoto, {Y}. and {V}ialard, {J}{\'e}r{\^o}me and {D}uncan, {B}.},
  editor = {},
  language = {{ENG}},
  abstract = {{P}revious studies have investigated how second-baroclinic-mode (n = 2) {K}elvin and {R}ossby waves in the equatorial {I}ndian {O}cean ({IO}) interact to form basin resonances at the semiannual (180 day) and 90-day periods. {T}his paper examines unresolved issues about these resonances, including the reason the 90-day resonance is concentrated in the eastern ocean, the time scale for their establishment, and the impact of complex basin geometry. {A} hierarchy of ocean models is used: an idealized one-dimensional (1{D}) model, a linear continuously stratified ocean model ({LCSM}), and an ocean general circulation model ({OGCM}) forced by {Q}uick {S}catterometer ({Q}uik{SCAT}) wind during 2000-08. {R}esults indicate that the eastern-basin concentration of the 90-day resonance happens because the westward-propagating {R}ossby wave is slower, and thus is damped more than the eastward-propagating {K}elvin wave. {R}esults also indicate that super-position with other baroclinic modes further enhances the eastern maximum and weakens sea level variability near the western boundary. {W}ithout resonance, although there is still significant power at 90 and 180 days, solutions have no spectral peaks at these periods. {T}he key time scale for the establishment of all resonances is the time it takes a {K}elvin wave to cross the basin and a first-meridional-mode (l = 1) {R}ossby wave to return; thus, even though the amplitude of the 90-day winds vary significantly, the 90-day resonance can be frequently excited in the real {IO}, as evidenced by satellite-observed and {OGCM}-simulated sea level. {T}he presence of the {I}ndian subcontinent enhances the influence of equatorial variability in the north {IO}, especially along the west coast of {I}ndia. {T}he {M}aldives {I}slands weaken the 180-day resonance amplitude but have little effect on the 90-day resonance, because they fall in its "node" region. {A}dditionally, resonance at the 120-day period for the n = 1 mode is noted.},
  keywords = {},
  booktitle = {},
  journal = {{J}ournal of {P}hysical {O}ceanography},
  volume = {41},
  numero = {6},
  pages = {1252--1270},
  ISSN = {0022-3670},
  year = {2011},
  DOI = {10.1175/2011jpo4591.1},
  URL = {https://www.documentation.ird.fr/hor/{PAR}00007715},
}