FN Archimer Export Format PT J TI Modal analysis of internal wave propagation and scattering over large-amplitude topography BT AF Lahaye, Noe Llewellyn Smith, Stefan G. AS 1:1;2:2; FF 1:;2:; C1 Univ. Brest, CNRS, IRD, Ifremer, Laboratoire d’Océanographie Physique et Spatiale (LOPS), IUEM, Brest, France Department of Mechanical and Aerospace Engineering, Jacobs School of Engineering and Scripps Insitution of Oceanography, UCSD, La Jolla CA, USA C2 CNES, FRANCE UNIV CALIF SAN DIEGO, USA SI BREST SE PDG-ODE-LOPS UM LOPS IF 3.373 TC 0 UR https://archimer.ifremer.fr/doc/00590/70186/68202.pdf LA English DT Article AB Coupled-mode equations describing the propagation and scattering of internal waves over large amplitude arbitrary topography in a two-dimensional stratified fluid are derived. They consist of a simple set of ordinary differential equations describing the evolution of modal amplitudes, based on an orthogonality condition that allows one to distinguish leftward and rightward propagating modes. The coupling terms expressing exchange of energy between mode are given in a analytical form using perturbation theory. This allows the derivation of a weak-topography approximate solution, generalizing previous linear solutions for a barotropic forcing (Llewellyn Smith and Young 2002). In addition, the orthogonality condition derived is valid for a different set of eigenmode defined on a sloping bottom, which shows a better convergence rate compared to the standard set of modes. The present work provides a useful and simple framework for the investigation of internal wave propagation in an inhomogeneous ocean, along with theoretical insight. PY 2020 SO Journal of Physical Oceanography SN 0022-3670 PU American Meteorological Society VL 50 BP 305 EP 321 DI 10.1175/JPO-D-19-0005.1 ID 70186 ER EF