Topographic height dependence of internal wave generation by tidal flow over random topography

Abstract

Internal waves (IWs) generated by tidal flow over the seafloor play a critical role in ocean circulation and climate. We determine the dependence of the radiated IW power on topographic parameters in numerical simulations of tidal flow over two‐dimensional random topographic profiles that have the spectrum of oceanic abyssal hills. The IW power increases as the horizontal spatial resolution scale is decreased, but below a certain spatial scale the power saturates at a level less than the linear theory prediction. For increasing topographic RMS height Hrms the emergent interference of the tide and the IWs from different generation sites leads to a transition in the IW power dependence on Hrms from quadratic to linear. This transition in the scaling of the IW power depends on the slopes of a valley's nearest neighboring peaks. Our results should guide the modeling of IW generation by tidal flow over small‐scale ocean topography.

Document Details

Document Type
Pub Defense Publication
Publication Date
Oct 08, 2015
Source ID
10.1002/2015gl065650

Entities

People

  • Harry L. Swinney
  • Jiajun Zhao
  • Likun Zhang

Organizations

  • Office of Naval Research
  • University of Texas at Austin

Tags

Fields of Study

  • Physics

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Irregular Warfare and Special Operations Cyberspace Operations against Adversarial Threats.
  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers