2014/10/01 by Jacques Vanneste, Vanneste, Jacques
Earth and Planetary Sciences · Engineering · Physics and Astronomy · #Atmospheric and Oceanic Physics (physics.ao-ph) #FOS: Physical sciences #Fluid Dynamics (physics.flu-dyn) #Geophysics and Sensor Technology #Seismic Waves and Analysis #physics.ao-ph #physics.flu-dyn
paper · pdf · doi:10.48550/arxiv.1410.0253
4 pages
arxiv created 2014/10/01 · openalex publication_date 2014/10/01 · arxiv updated 2014/10/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Oceanic near-inertial waves - internal waves with frequencies close to the local Coriolis frequency f0 - are strongly influenced by the presence of mean currents. To study this influence, Young and Ben Jelloul (1997) derived an asymptotic model that describes the slow modulation of the amplitude of these waves about their rapid oscillation at frequency f0. Here we show that this model can be obtained within a variational framework, by (Whitham) averaging the Lagrangian of the hydrostatic-Boussinesq equations over the wave period 2π/f0. The derivation leads to a variational formulation of the Young-Ben Jelloul model from which its conservation laws can be obtained systematically.