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This content will become publicly available on February 25, 2026

Title: Scattering of surface waves by ocean currents: the U2H map
Ocean turbulence at meso- and submesocales affects the propagation of surface waves through refraction and scattering, inducing spatial modulations in significant wave height (SWH). We develop a theoretical framework that relates these modulations to the current that induces them. We exploit the asymptotic smallness of the ratio of typical current speed to wave group speed to derive a linear map – the U2H map – between surface current velocity and SWH anomaly. The U2H map is a convolution, non-local in space, expressible as a product in Fourier space by a factor independent of the magnitude of the wavenumber vector. Analytic expressions of the U2H map show how the SWH responds differently to the vortical and divergent parts of the current, and how the anisotropy of the wave spectrum is key to large current-induced SWH anomalies. We implement the U2H map numerically and test its predictions against WAVEWATCH III numerical simulations for both idealised and realistic current configurations.  more » « less
Award ID(s):
2048583
PAR ID:
10581369
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Cambridge University Press
Date Published:
Journal Name:
Journal of Fluid Mechanics
Volume:
1005
Issue:
A12
ISSN:
0022-1120
Page Range / eLocation ID:
1-24
Subject(s) / Keyword(s):
air/sea interactions wave-turbulence interactions surface gravity waves
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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