Speaker: Michal Shavit (NYU)

Title: Weak turbulence of 2D internal gravity waves

Abstract:

Our work addresses a long-standing problem: describing internal wave turbulence in the ocean from the governing equations.
A promising avenue lies in the kinetic approach. But the stratified Euler equations form an anisotropic, non-canonical Hamiltonian system, making the classical wave-turbulence approach inapplicable.
We take a new route: studying the singular limit of vanishing rotation, where rotation acts as a regulator near the curve of zero-frequency slow modes. This regime is both mathematically tractable and oceanographically relevant. In this limit, we derive the turbulent spectrum of 2D weakly interacting internal gravity waves, which matches the celebrated Garrett–Munk spectrum known from observations, for the first time from first principles.