Coastal upwelling observed off the East coast of Korea and variability of passive sound detection environment

Sang-Shin Byun; Chang-Bong Cho

doi:10.7776/ASK.2022.41.6.601

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2022 Vol.41, Issue 6 Next Page

Research Article

Coastal upwelling observed off the East coast of Korea and variability of passive sound detection environment 동해 연안에서 관측된 용승현상과 수동 음탐환경의 변화

30 November 2022. pp. 601-609

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Abstract

In August 2007, coastal upwelling occurred off the east coast of Korea, and vertical water temperature and salinity data were obtained from a real-time surface ocean buoy. Based on the time series observation data, a vertical sound velocity structure was calculated before, during, and after the occurrence of the coastal upwelling, and how the coastal upwelling affects the sound propagation and detection environment through acoustic modeling considering the horizontal scale and actual seabed topography. As a result of comparing and analyzing the low-frequency (500 Hz) sound transmission loss and the target detection range by depth using the parabolic equation model, it was analyzed that if coastal upwelling occurs, a detection gain of up to about 10 dB can be expected. In addition, through this study, it was confirmed that the characteristics of sound propagation can be greatly changed even in a short period of about 2 to 3 days before and after coastal upwelling.

Keywords

East coast of Korea

Coastal upwelling

Sound propagation

Detection environment

Detection gain

2007년 8월 동해 연안에서 연안용승 현상이 발생 되었고, 이에 따른 수직적인 수온과 염분 자료가 실시간 해양관측부이를 통해 획득되었다. 시계열 관측자료를 기반으로 연안용승 발생 전·중·후의 수직적인 음속구조를 산출하였고, 연안용승의 수평적인 규모와 실제 해저지형 등을 고려한 음향모델링을 통해 연안용승이 수중의 음파 전달과 탐지환경에 어떠한 영향을 미치는지 분석하였다. 포물선 방정식 모델을 이용한 저주파(500 Hz) 음파 전달손실과 심도별 표적 탐지거리를 비교·분석한 결과, 동해 연안에서 용승이 발생하면 그렇지 않은 일반적인 음탐환경에 비해 최대 약 10 dB의 탐지이득을 기대할 수 있는 것으로 분석되었다. 또한, 이번 연구를 통해 용승 전·후 약 2 ~ 3일의 짧은 기간 내에서도 음파전달 특성이 크게 달라질 수 있음을 확인하였다.

키워드

동해연안

연안용승

음파전달

탐지환경

탐지이득

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Information

Publisher :The Acoustical Society of Korea
Publisher(Ko) :한국음향학회
Journal Title :The Journal of the Acoustical Society of Korea
Journal Title(Ko) :한국음향학회지
Volume : 41
No :6
Pages :601-609
Received Date : 2022-07-05
Revised Date : 2022-08-26
Accepted Date : 2022-10-05
DOI :https://doi.org/10.7776/ASK.2022.41.6.601

The Journal of the Acoustical Society of KoreaISSN:1225-4428(Print) 2287-3775(Online)한국음향학회

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