Examination of the North Pacific Ocean in the Spectral Domain Using GeosatAltimeter Data and a Numerical Ocean Model

摘要

The sea surface height (SSH) variations of the North Pacific ocean and theKuroshio Extension region, in particular, are examined by frequency and wavenumber decompositions of a 1/80, six-layer primitive equation Pacific Ocean model and of the Geosat Exact Repeat Mission (ERM) data. Both data sets exhibit peaks in variability at 1 and 2 cycles per year over much of the Kuroshio Extension region. Annual variations of equatorial currents in both data sets are similar in both space and time, with the variations in the South Equatorial Current appearing as annual westward propagations. Annual variations in the strength of the Kuroshio Extension are manifested mainly through changes in the strength of the recirculation gyres on the southern side of the current. Annual transport maxima for the Kuroshio Extension occur around late October for both the model and Geosat.