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Title: Inertia-gravity waves and geostrophic turbulence
Inertia-gravity waves in the atmosphere and ocean are transported and refracted by geostrophic turbulent currents. Provided that the wave group velocity is much greater than the speed of geostrophic turbulent currents, kinetic theory can be used to obtain a comprehensive statistical description of the resulting interaction (Savva et al. , J. Fluid Mech. , vol. 916, 2021, A6). The leading-order process is scattering of wave energy along a surface of constant frequency, $\omega$ , in wavenumber space. The constant- $\omega$ surface corresponding to the linear dispersion relation of inertia-gravity waves is a cone extending to arbitrarily high wavenumbers. Thus, wave scattering by geostrophic turbulence results in a cascade of wave energy to high wavenumbers on the surface of the constant- $\omega$ cone. Solution of the kinetic equations shows establishment of a wave kinetic energy spectrum $\sim k_h^{-2}$ , where $k_h$ is the horizontal wavenumber.  more » « less
Award ID(s):
2048583
NSF-PAR ID:
10411607
Author(s) / Creator(s):
Date Published:
Journal Name:
Journal of Fluid Mechanics
Volume:
920
ISSN:
0022-1120
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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