Article
 

Oceanic Isopycnal Slope Spectra. Part I: Internal Waves

Öffentlich Deposited

Herunterladbarer Inhalt

PDF Herunterladen
https://ir.library.oregonstate.edu/concern/articles/dv13zv85z

Descriptions

Attribute NameValues
Creator
Abstract
  • Horizontal tow measurements of internal waves are rare and have been largely supplanted in recent decades by vertical profile measurements. Here, estimates of isotherm displacements and turbulence dissipation rate from a towed vehicle deployed near Hawaii are presented. The displacement data are interpreted in terms of horizontal wavenumber spectra of isopycnal slope. The spectra span scales from 5 km to 0.1 m, encompassing both internal waves and turbulence. The turbulence subrange is identified using a standard turbulence fit, and the rest of the motions are deemed to be internal waves. The remaining subrange has a slightly red slope (ϕ ~ kₓ⁻¹/²) and vertical coherences compatible with internal waves, in agreement with previous towed measurements. However, spectral amplitudes in the internal wave subrange exhibit surprisingly little variation despite a four-order-of-magnitude change in turbulence dissipation rate observed at the site. The shape and amplitude of the horizontal spectra are shown to be consistent with observations and models of vertical internal wave spectra that consist of two subranges: a “linear” subrange (ϕ ~ k⁰𝓏) and a red “saturated” subrange (ϕ ~ k𝓏⁻¹). These two subranges are blurred in the transformation to horizontal spectra, yielding slopes close to those observed. The saturated subrange does not admit amplitude variations in the spectra yet is an important component of the measured horizontal spectra, explaining the poor correspondence with the dissipation rate.
Resource Type
DOI
Date Available
Date Issued
Citation
  • Klymak, Jody M., James N. Moum, 2007: Oceanic Isopycnal Slope Spectra. Part I: Internal Waves. J. Phys. Oceanogr., 37, 1215–1231.
Journal Title
Journal Volume
  • 37
Journal Issue/Number
  • 5
Urheberrechts-Erklärung
Funding Statement (additional comments about funding)
  • This work was funded by the National Science Foundation Grants 9819531 and 9819522.
Publisher
Peer Reviewed
Language
Replaces

Beziehungen

Parents:

This work has no parents.

Artikel