Journal of Korea Water Resources Association (한국수자원학회논문집)

Korea Water Resources Association (한국수자원학회)
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A modification of the rip current warning system utilizing real-time observations: a database function of likelihood distributions

실시간 관측정보를 이용한 이안류 경보체계 개선 연구: 발생정도 DB함수의 활용

  • Choi, Junwoo (Coastal Research Laboratory, Department of Hydro Science and Engineering Research, Korea Institute of Civil Engineering & Building Technology)
  • 최준우 (한국건설기술연구원 수자원하천연구본부)
  • Received : 2022.09.08
  • Accepted : 2022.10.03
  • Published : 2022.10.31
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Abstract

For the rip current warning system to reduce rip-current accidents, the implementation method producing the risk index was modified. To produce fast response from the warning system based on real-time observations, the method employed the numerical results (i.e., rip current likelihoods according to the possible scenario) obtained in advance. In this study, instead of using the empirical curve-fitting functions of the previous method, the present modification utilized two-dimensional distributions (i.e., wave height and period, wave height and tidal elevation, wave height and direction, wave height and spreading of frequency-directional spectrum) of rip current likelihoods stacked in a database of the system. The wave and tidal observations in 2021 at the Haeundae coast were applied to the modified system, and its performances at several real events recorded in CCTV images were presented.

이안류 안전사고 저감을 목적으로 운영되는 실시간 이안류 경보체계에서 위험지수를 생산하는 방법을 개선하는 연구를 수행하였다. 상기 체계는 실시간 관측정보를 기반으로 신속한 이안류 위험지수를 생산할 필요가 있기 때문에 사전 수치모의 결과(즉, 발생가능 시나리오에 따른 이안류 발생정도)를 이용한다. 본 연구에서는 기존 기법의 곡선적합 경험식을 사용하는 대신에, 다변수 함수인 이안류 발생정도를 2차원 분포(예, 파고-주기, 파고-조위, 파고-파향, 파고-주파수 스펙트럼 광협도, 파고-파향 스펙트럼 광협도)로 저장하여 사용하므로 이안류 위험지수 생산 기법을 개선하였다. 2021년에 운영된 해운대 파랑 관측자료와 부산조위소의 조위정보를 개선된 방법에 적용하였고, CCTV를 통해 확인된 몇 차례의 이안류 발생사건에 대하여 관측정보와 적용한 결과를 비교하여 제시하였다.

Keywords

Acknowledgement

본 연구는 해양수산부 국립해양조사원의 "실시간 이안류 감시체계 확대 및 서비스" 사업의 지원으로 수행되었습니다.

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