FN Archimer Export Format
PT J
TI Sea-level variability and semiannual rossby waves in the South-Atlantic subtropical gyre
BT 
AF LE TRAON, Pierre-Yves
   MINSTER, JF
AS 1:;2:;
FF 1:;2:;
IF 2.68
TC 24
UR https://archimer.ifremer.fr/doc/00078/18974/16623.pdf
LA English
DT Article
AB We derived the sea level variability in the South Atlantic subtropical gyre between 15-degrees and 35-degrees-S from 2 years of the Geosat exact repeat mission altimeter data. On the mesoscale, along-track wavenumber spectra are those of nonlinear dynamics with a steeper slope and stronger energy along the eastern boundary. Frequency/wavenumber spectra reveal a significant semiannual signal at a wavelength of about 500 km. West of the Walvis ridge (5-degrees-E), this signal appears to correspond to semiannual Rossby waves of 2- to 3-cm amplitude, propagating westward at 3 cm s-1, and showing latitude refraction effects. The pattern is very similar to that of annual Rossby waves as modeled by Reason et al. (1987). These waves are probably related to the semiannual wind component. However, understanding the exact mechanism for their excitation requires dynamical modeling. The large-scale variability also shows a significant semiannual component (about 6-cm amplitude and 15% of the yearly variance) in phase with climatological winds.
PY 1993
PD JUN
SO Journal Of Geophysical Research-oceans
SN 0148-0227
PU AGU
VL 98
IS C7
UT A1993LN31000003
BP 12315
EP 12326
DI 10.1029/93JC00456
ID 18974
ER

EF