Skip to main content
padlock icon - secure page this page is secure

Free Content A composite vertical current spectrum for strongly and weakly stratified seas and oceans

Download Article:
(PDF 6,310.3 kb)
An overall frequency (σ) spectrum φ w (σ, N, fh ) is composed for vertical current (w) observations from ocean areas with different stratifications represented by large, 100 m scale buoyancy frequency N. The horizontal Coriolis parameter is denoted by fh . In the open Atlantic Ocean, the relatively strong horizontal layering in density supports the φ w that is found in semiequilibrium under the degradation of the lowest internal wave mode. This φ w is not constant with frequency; however, its variance increases between σ = f and its peak near σ = (0.5 – 0.7) N >> f, where f denotes the local inertial frequency. In contrast, the φ w spectra from the weakly stratified deep Mediterranean and from the shallow North Sea peak at ∼ 1.1 f, except for a tidal peak in North Sea data, and fall off at a rate of σ–1 for 1.1 f < σ < Nm = 4fh , where Nm denotes maximum small-scale N. Background conditions are characterized by vertical instead of horizontal layering in density. Such spectra are best described by a nonequilibrium evolution of small-scale internal waves under a weak mean shear, which transfers variance to σ ≈ f. This φ w Np , p > 0, is contrary to the existing model of open-ocean equilibrium spectra that decrease with N (p < 0). A smooth transition between the two regimes is found to coincide with top-peak φ w for N/fh = 4.
No References for this article.
No Supplementary Data.
No Article Media
No Metrics


Document Type: Research Article

Publication date: January 1, 2015

More about this publication?
  • The Journal of Marine Research, one of the oldest journals in American marine science, publishes peer-reviewed research articles covering a broad array of topics in physical, biological and chemical oceanography. Articles that deal with processes, as well as those that report significant observations, are welcome. Biological studies involving coupling between ecological and physical processes are preferred over those that report systematics. The editors strive always to serve authors and readers in the academic oceanographic community by publishing papers vital to the marine research in the long and rich tradition of the Sears Foundation for Marine Research. We welcome you to the Journal of Marine Research.
  • Editorial Board
  • Information for Authors
  • Subscribe to this Title
  • Purchase The Sea
  • Ingenta Connect is not responsible for the content or availability of external websites
  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more