Numerical Simulations of Internal Tide Dynamics in a Steep Submarine Canyon
Abstract
This study investigates three-dimensional semidiurnal internal tide (IT) energetics in the vicinity of La Jolla Canyon, a steep shelf submarine canyon off the Southern California coast, with the Stanford Unstructured Nonhydrostatic Terrain-Following Adaptive Navier–Stokes Simulator (SUNTANS) numerical simulator. Numerical simulations show vertical structure and temporal phasing consistent with detailed field observations. ITs induce large (approximately 34 m from peak to peak) isotherm displacements and net onshore IT energy flux up to 200 W m−1. Although the net IT energy flux is onshore, the steep supercritical slope around the canyon results in strong reflection. The model provides the full life span of internal tides around the canyon, including internal tide generation, propagation, and dissipation. ITs propagate into the canyon from the south and are reflected back toward offshore from the canyon’s north side. In the inner part of the canyon, elevated mixing occurs in the middle layer due to an interaction between incident mode-1 ITs and reflected higher-mode ITs. The magnitude of IT flux, generation, and dissipation on the south side of the canyon are higher than those on the north side. An interference pattern in horizontal kinetic energy and available potential energy with a scale of approximately 20–50 km arises due to low-mode wave reflections. Our results provide new insight into IT dynamics associated with a small-scale canyon topography.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 01, 2023
- Source ID
- 10.1175/jpo-d-23-0040.1
Entities
People
- Andrea Rodriguez-marin Freudmann
- Andrew J. Lucas
- Eiji Masunaga
- Matthew H. Alford
Organizations
- Ibaraki University
- Japan Society for the Promotion of Science
- Office of Naval Research Global
- University of California
- University of California, San Diego