Using a regional ocean model to understand the structure and variability of acoustic arrivals in Fram Strait

Abstract

A regional ocean model for Fram Strait provides a framework for interpretation of the variability and structure of acoustic tomography arrivals. The eddy-permitting model (52 vertical levels and 4.5 km horizontal resolution) was evaluated using long-term moored hydrography data and time series of depth-range averaged temperature obtained from the inversion of acoustic tomography measurements. Geometric ray modeling using the ocean model fields reproduces the measured arrival structure of the acoustic tomography experiment. The combination of ocean and acoustic models gives insights into acoustic propagation during winter and spring. Moreover, overlapping arrivals coming from different vertical angles can be resolved and explained. The overlapping arrival of purely refracted rays and surface-reflected/bottom-reflected (SRBR) rays has implications for the inversion of tomography data in Fram Strait. The increased knowledge about the ray-length variations of SRBR rays is valuable for choosing appropriate observation kernels for the data assimilation of acoustic tomography data in Fram Strait.

Document Details

Document Type
Pub Defense Publication
Publication Date
Feb 01, 2020
Source ID
10.1121/10.0000513

Entities

People

  • Bruce D. Cornuelle
  • Florian Geyer
  • Hanne Sagen
  • Heriberto J. Vázquez
  • Matthew R. Mazloff

Organizations

  • Nansen Environmental and Remote Sensing Center
  • National Aeronautics and Space Administration
  • National Science Foundation
  • Office of Naval Research Global
  • University of California, San Diego

Tags

Readers

  • Acoustical Oceanography.
  • Computational Modeling and Simulation
  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers