A modification of the rip current warning system utilizing real-time observations: a database function of likelihood distributions

Junwoo Choi

doi:10.3741/JKWRA.2022.55.10.843

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2022 Vol.55, Issue 10 Preview Page

Technical Note

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

31 October 2022. pp. 843-854

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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.

Keywords

Rip-current warning system

Rip-current risk index

Rip-current likelihood

Real-time observation

Numerical simulation

Haeundae beach

FUNWAVE

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.

키워드

이안류 경보

이안류 위험지수

이안류 발생정도

실시간 관측

수치모의

해운대

FUNWAVE

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Information

Publisher :KOREA WATER RESOURECES ASSOCIATION
Publisher(Ko) :한국수자원학회
Journal Title :Journal of Korea Water Resources Association
Journal Title(Ko) :한국수자원학회 논문집
Volume : 55
No :10
Pages :843-854
Received Date : 2022-09-08
Revised Date : 2022-09-27
Accepted Date : 2022-10-03
DOI :https://doi.org/10.3741/JKWRA.2022.55.10.843

Journal of Korea Water Resources Association ISSN:2799-8746(Print) 2799-8754(Online) 한국수자원학회 논문집

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