Journal of Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회논문집)

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
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A Study on Calibration of Underestimated Wave Heights Measured by Wave and Tide Gauge (WTG)

저평가된 수압식 파고계(WTG) 관측 파고값 보정방안 연구

  • Jeong, Weon Mu (Maritime ICT R&D Center, Korea Institute of Ocean Science and Technology) ;
  • Chang, Yeon S. (Maritime ICT R&D Center, Korea Institute of Ocean Science and Technology) ;
  • Oh, Sang-Ho (Coastal Development and Ocean Energy Research Center, Korea Institute of Ocean Science and Technology) ;
  • Baek, Won Dae (Maritime ICT R&D Center, Korea Institute of Ocean Science and Technology)
  • 정원무 (한국해양과학기술원 해양ICT융합연구센터) ;
  • 장연식 (한국해양과학기술원 해양ICT융합연구센터) ;
  • 오상호 (한국해양과학기술원 연안개발.에너지연구센터) ;
  • 백원대 (한국해양과학기술원 해양ICT융합연구센터)
  • Received : 2020.08.13
  • Accepted : 2020.09.09
  • Published : 2020.10.31
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Abstract

It has been reported that the wave heights measured by Wave and Tide gauges (WTG) have been underestimated, and thus it is important to improve its measuring accuracy for enhancing estimation of harbor tranquility. In this study, the significant wave heights from WTG were calibrated using measured data from AWAC and Waverider buoys moored at the same four locations with the WTG. It was observed that the product of significant wave height and peak wave period, HT, was not underestimated but linearly proportional between the measurements by two instruments. This linearity was applied to develop 3rd order polynomial functions that best represented the relationship between HT and significant wave heights measured by WTG. These functions were then applied to calibrate the WTG significant wave heights that were lower than 0.7 m, the critical value established for the low waves in this study. The results showed that the linearity between the AWAC (or Waverider buoy) and calibrated wave heights were improved, and the magnitude of underestimated WTG wave heights were increased to be more realistic. The results of this study are expected to be effectively applied for other data sets obtained by WTG only, to increase the observation accuracy of WTG and to improve the estimation of harbor tranquility.

수압식 파고계(WTG)로 관측한 파고가 저파랑 환경에서 저평가되는 문제가 제기되어 왔으며 이 자료를 보정하여 관측오차를 줄이는 것은 WTG 실측자료를 사용해 항만정온도 기준을 개선하는데 매우 중요하다고 할 수 있다. 본 연구에서는 네 지점에서 관측한 AWAC 및 부이식 파고계(Waverider buoy) 자료를 사용하여 동일 지점에서 관측한 WTG 유의파고를 보정하였다. 먼저 저파랑 조건 하에서 WTG 유의파고(Hm0) 값이 저평가되는 경우에도 유의파고와 첨두주기의 곱인 WTG HT는 저평가되지 않고 AWAC 및 부이식 파고계의 HT와 선형관계를 유지함을 발견하였으며, 이 선형성을 적용하여 WTG HT와 Hm0 간의 분포를 대표하는 3차 함수를 각 지점 별로 산정하였다. 이 함수를 사용하여 저파랑 임계파고로 설정한 0.7 m 이하의 WTG Hm0를 보정하였으며, 그 결과 보정된 WTG Hm0와 AWAC 및 Waverider buoy Hm0의 선형관계가 향상되었고 저평가되었던 파고도 상당부분 개선되었음을 확인하였다. 본 연구 결과를 적용하면 HT의 선형성이 유지되는 타 지역의 WTG 관측 파고를 보정하는 일과, 나아가 보다 정확한 실측자료를 제공해 해당 항만의 개선된 정온도 기준을 마련하는 일에 기여할 수 있을 것으로 예상된다.

Keywords

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