Cross-Slope Acoustic Scattering and Transmission Experiment (CASTEx) in the Northeastern South China Sea

Abstract

Sound transmission in the sloping environment of the South China Sea (SCS) shows inherent spatial and temporal instabilities or fluctuations that can be attributed to environmental factors. From 2001 to 2015, a series of joint TaiwaneseU.S. field experiments were conducted in the SCS, for example ASIAEX, VNAS/WISE, and SCOPE/NLIWI; further, sand dune acoustic experiments were also conducted to survey the regional oceanic variabilities and the temporal and spatial variabilities in acoustic propagation in the SCS. The synthesis of the acoustic results obtained through experimentation provides information on the nature of dependency of signal fluctuations on the locale, orientation, range, and strength of nonlinear internal waves (NIWs); the acoustic results also provide insights into the subaqueous sand waves. However, the combined effects of NIWs, sand waves, and topographic variation are still unknown. Further, the potential impact on long-range cross-slope acoustic transmission, with respect to both phenomenology and statistics, is also not clearly understood. To address these issues, we focus on the existing problems on acoustic variations in the northeastern (NE) SCS, from the upper slope, through areas with bedforms and shelf break, and to the shelf regime. Subsequently, the areas are accessed contrariwise as well.

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Document Details

Document Type
Technical Report
Publication Date
Dec 26, 2020
Accession Number
AD1118654

Entities

People

  • Yung-sheng Chiu

Tags

Communities of Interest

  • Sensors

DTIC Thesaurus Topics

  • Acoustic Equipment
  • Acoustic Propagation
  • Acoustic Scattering
  • Acoustics
  • Chirp Sonar
  • Core Sampling
  • Data Analysis
  • Deployment
  • Frequency
  • Grain Size
  • Internal Waves
  • Measurement
  • Reflection
  • Scattering
  • Solitons
  • Sonar
  • Sound Transmission
  • South China Sea
  • Surveys
  • Three Dimensional
  • Two Dimensional
  • Waves

Readers

  • Coastal Oceanography
  • Urban Planning and Geography.
  • Wave Propagation and Nonlinear Chaotic Dynamics.