Journal of Oceanography

, Volume 63, Issue 3, pp 483–490 | Cite as

Frequency-wavenumber spectra of equatorial waves detected from satellite altimeter data

  • Yoshinobu Wakata
Short Contribution


The sea surface height anomaly in the Pacific equatorial area was separated into equatorial modes using satellite altimeter data. The power-spectral density (PSD) was obtained for the east-west wavenumber and frequency for each separated mode. The PSD distribution was compared with the theoretical dispersion curve for the equatorial modes derived by Matsuno (1966). The first Rossby modes have a high-density distribution that is slightly lower than the theoretical dispersion curve, but the Kelvin mode and the higher Rossby modes have high-density distribution that almost matches each dispersion curve. Results of analyses of satellite observational data show that wave motion near the equator mainly shows characteristics of equatorial waves, especially for a intraseasonal time scale.


Equatorial wave mode separation TOPEX/POSEIDON sea surface height Pacific Ocean 


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Copyright information

© The Oceanographic Society of Japan/TERRAPUB/Springer 2007

Authors and Affiliations

  1. 1.Research Institute for Applied MechanicsKyushu UniversityKasuga-kohen, Kasuga-shi, FukuokaJapan

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