Show simple item record

contributor authorFarrar, J. Thomas
date accessioned2017-06-09T16:20:26Z
date available2017-06-09T16:20:26Z
date copyright2008/08/01
date issued2008
identifier issn0022-3670
identifier otherams-66069.pdf
identifier urihttp://onlinelibrary.yabesh.ir/handle/yetl/4207364
description abstractSpectral techniques applied to altimetry data are used to examine the dispersion relation and meridional sea level structure of wavelike variability with periods of about 20 to 200 days in the equatorial Pacific Ocean. Zonal wavenumber?frequency power spectra of sea surface height, when averaged over about 7°S?7°N, exhibit spectral peaks near the theoretical dispersion curves of first baroclinic-mode equatorial Kelvin and Rossby waves. There are distinct, statistically significant ridges of power near the first and second meridional-mode Rossby wave dispersion curves. Sea level variability near the theoretical Kelvin wave and first meridional-mode Rossby wave dispersion curves is dominantly (but not perfectly) symmetric about the equator, while variability near the theoretical second meridional-mode Rossby wave dispersion curve is dominantly antisymmetric. These results are qualitatively consistent with expectations from classical or shear-modified theories of equatorial waves. The meridional structures of these modes resemble the meridional modes of equatorial wave theory, but there are some robust features of the meridional profiles that were not anticipated. The meridional sea level structure in the intraseasonal Kelvin wave band closely resembles the theoretically expected Gaussian profile, but sea level variability coherent with that at the equator is detected as far away as 11.75°S, possibly as a result of the forced nature of these Kelvin waves. Both first and second meridional-mode Rossby waves have larger amplitude in the Northern Hemisphere. The meridional sea level structure of tropical instability waves closely resembles that predicted by Lyman et al. using a model linearized about a realistic equatorial zonal current system.
publisherAmerican Meteorological Society
titleObservations of the Dispersion Characteristics and Meridional Sea Level Structure of Equatorial Waves in the Pacific Ocean
typeJournal Paper
journal volume38
journal issue8
journal titleJournal of Physical Oceanography
identifier doi10.1175/2007JPO3890.1
journal fristpage1669
journal lastpage1689
treeJournal of Physical Oceanography:;2008:;Volume( 038 ):;issue: 008
contenttypeFulltext


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record