Nonlinearity in the oceans: what lies beneath?
Laboratoire de Physique, ENS Lyon
We present on overview of the physics of internal gravity waves, these being hydrodynamic waves beneath the ocean surface, which have unexpected properties for a physicist. We begin by focusing on the generation of localized waves at the interface between sharply defined layers of different fluid density, before proceeding to consider internal gravity waves in more realistic systems with continuous density stratification. Using experiments ranging from simple to elaborate, in combination with fundamental theoretical ideas, the talk will elucidate striking nonlinear phenomena of internal gravity waves, including: the formation of the largest amplitude internal solitary waves on record, the focusing of energy by internal wave attractors, and the cascade towards internal wave driven turbulence.