Near-inertial wave propagation between stratified and homogeneous layers: Simulating transition

22 May 2024


(1) Hans van Haren, NIOZ Royal Netherlands Institute for Sea Research, P.O. Box 59, 1790 AB Den Burg, the Netherlands.

Abstract and Intro



Simulating Transition


Conclusions and References

4 Simulating transition

Following modelling by Gerkema and Exarchou (2008), an instantaneous solution of a linear 2-D z,y flat-bottom analytic simulation of IGW-propagation using 20 vertical modes in a non-traditional approach shows propagating waves from left to right, crossing an interface between homogeneous and uniformly stratified layers (Fig. 7). A single fixed frequency of motions is used in the calculation. Here, only results are shown for near-inertial frequency vertical motions, albeit distinction is studied between just-super- and just-sub-inertial motions. Only frequencies are chosen in the range (1) that will yield free IGW-propagation in both layers. This naturally limits the frequency-range to near-inertial frequencies.

In principle, the above simulation could compare well with some of the observations of abrupt phase changes in amplitude and direction of w across abrupt changes in density, provided we can transfer [z, t] to [z, y]. However, this is not so obvious (see also Gerkema and Exarchou (2008), despite some of the similar qualitative results given above, notably the abrupt changes in phase and associated amplitude variations.

This paper is available on arxiv under CC 4.0 license.