Over het archief
Het OWA, het open archief van het Waterbouwkundig Laboratorium heeft tot doel alle vrij toegankelijke onderzoeksresultaten van dit instituut in digitale vorm aan te bieden. Op die manier wil het de zichtbaarheid, verspreiding en gebruik van deze onderzoeksresultaten, alsook de wetenschappelijke communicatie maximaal bevorderen.
Dit archief wordt uitgebouwd en beheerd volgens de principes van de Open Access Movement, en het daaruit ontstane Open Archives Initiative.
Basisinformatie over ‘Open Access to scholarly information'.
A composite vertical current spectrum for strongly and weakly stratified seas and oceans
In: Journal of Marine Research. Sears Foundation for Marine Research, Yale University: New Haven, Conn.. ISSN 0022-2402; e-ISSN 1543-9542, meer
|  |
| Author keywords |
COMPOSITE OCEAN SPECTRUM; INTERNAL WAVES; MIXING EFFECTS; VERTICAL MOTIONS; WEAK AND STRONG STRATIFICATION |
| Abstract |
An overall frequency (s) spectrum f w (s, 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 f w that is found in semiequilibrium under the degradation of the lowest internal wave mode. This f w is not constant with frequency; however, its variance increases between s = f and its peak near s = (0.5 – 0.7) N >> f, where f denotes the local inertial frequency. In contrast, the f 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 s–1 for 1.1 f < s < 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 s ˜ f. This f 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 f w for N/fh = |
IMIS is ontwikkeld en wordt gehost door het VLIZ.
