in the present work properties of rossby and inertia gravity waves are investigated based on proper orthogonal decomposition (pod) functions. the pod functions are constructed using analytical, experimental or numerical data recorded as snapshots. the pod basis can be carried out to make a reduced order model by galerkin projection of governing equations onto these functions. in this paper, the...

the spontaneous generation of inertia–gravity waves (igws) in the idealized simulation of vortical flows is investigated using the isentropic two-layer model on a sphere. the contour-advective semi-lagrangian (casl) algorithm is applied to solve the primitive equations using the potential vorticity (pv), velocity divergence, and acceleration divergence as the prognostic variables. the casl algo...

After reviewing the background, this article discusses the recently discovered examples of hybrid propagating structures consisting of vortex dipoles and comoving gravity waves undergoing wave capture. It is shown how these examples fall outside the scope of the Lighthill theory of spontaneous imbalance and, concomitantly, outside the scope of shallow-water dynamics. Besides the fact that going...

We present an experimental and modelling study of a strong gravity wave event in the upper troposphere/lower stratosphere near the Scandinavian mountain ridge. Continuous VHF radar measurements during the MaCWAVE rocket and ground-based measurement campaign were performed at the Norwegian Andoya Rocket Range (ARR) near Andenes (69.3 N, 16 E) in January 2003. Detailed gravity wave investigations...

balance, breakdown of balance, and generation of inertia–gravity waves in vortical flows are fundamental topics of prime importance in geophysical fluid dynamics. this research aims to find the optimum balance relation as well as the rossby-number variation of the spontaneous generation of inertia–gravity waves in a baroclinic, two-layer, boussinesq model on a doubly-periodic f-plane geometry f...

Resonant excitation of coastal Kelvin waves by free inertia–gravity waves impinging on the coast is studied in the framework of the simplest baroclinic model: two-layer rotating shallow water with an idealized straight coast. It is shown that, with respect to the previous results obtained with the one-layer model, new resonances leading to a possible excitation of Kelvin waves appear. The most ...

Using a fine resolution numerical model (40002 × 2 grid-points) of the two-layer shallow-water equations of the mid-latitude β-plane dynamics, it is shown that there is no sudden breakdown of balance in the turbulent enstrophy cascade but a faint and continuous emission of inertia–gravity waves. The wave energy accumulates in the equator-ward region of the domain due to the Coriolis parameter d...