Instabilities of Internal Gravity Wave Beams: insights from experimental and analytical approaches
Internal gravity waves play a primary role in geophysical fluids: they contribute significantly to mixing in the ocean and they redistribute energy and momentum in the middle atmosphere. Until recently, most of the studies were focused on plane-wave solutions. However, these solutions are not a satisfactory description of most geophysical manifestations of internal gravity waves, and it is now recognized that internal wave beams with a locally confined profile are ubiquitous in the geophysical context.

We will discuss the reason for their ubiquity in stratified fluids, since they are solutions of the nonlinear governing equations. Moreover, in the light of the recent experimental and analytical studies of those internal gravity beams, it is timely to discuss the two main mechanisms of instability for those beams: the triadic resonant instability and the streaming instability.
Date: 20 February 2017, 11:30
Venue: Atmospheric, Oceanic and Planetary Physics, off Parks Road OX1 3PU
Venue Details: Dobson Lecture Room
Speaker: Thierry Dauxois (Ecole Normale Superieure de Lyon)
Organising department: Department of Physics
Organiser: Andrew Wells (Atmospheric, Oceanic & Planetary Physics, University of Oxford; & Wolfson College)
Part of: Geophysical & Nonlinear Fluid Dynamics Seminars
Booking required?: Not required
Audience: Members of the University only
Editor: Andrew Wells