Journal of Advanced Marine Engineering and Technology

The Korean Society of Marine Engineering (한국마린엔지니어링학회)
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Wave and surface current measurement with HF radar in the central east coast of Korea

동해중부에서 HF Radar를 이용한 파랑 및 해수유동 관측

  • Received : 2014.02.07
  • Accepted : 2014.07.10
  • Published : 2014.07.31
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Abstract

We installed HF Radar of Array type in Site A and Site B, observing the real-time wave and current in the central East coast of Korea. WERA(WavE RAdar) in this research uses HF Radar of Array Type with frequency range of 24.525 MHz, developed by Helzel, Germany. Each site is a 8-Channel system consisting of four transmitters and eight receivers, generating wave and current data, being observed every thirty minutes at the present time. HF Radar has grid resolution of an interval of 1.5 km using bandwidth of 150 kHz; The wave data covers an observation range of about 25 km, and the current data covers the maximum observation range of about 50 km. The Wave data observed by HF Radar was compared and verified with the AWAC data observed in the research sites. MIT also compared the Current data observed by HF Radar with Monthly the East sea average surface current and current flow pattern provided by KOHA(Korea Hydrographic and oceanographic Administration). The regression line and deviation of the comparison data of Wave was calculated by Principal Component Analysis, which showed correlation coefficient 0.86 and RMSD 0.186. Besides, data analysis of long-term changes of the current in the East coast showed that, during August and September, the North Korean Cold Current flow into the southward direction and the East Korean Warm Current flow into the northward direction in the coast.

배열형(Array type)의 HF Radar를 임원항(Site A)과 후정리 해변(Site B)에 설치하여 동해연안에 대한 실시간 파랑과 해류를 관측하였다. 본 연구에 사용된 WERA (WavE RAdar)는 2000년 독일 Helzel사에서 개발된 것으로 24.525 MHz의 주파수 대역을 사용한다. 각 사이트는 4기의 송신기와 8기의 수신기로 구성되어 있는 8 채널 시스템이며, 현재 30분 주기로 관측하여 자료를 생성하고 있다. 파랑은 최대 약 25 km, 해류는 최대 약 50 km의 관측 범위를 나타내며, 150 kHz의 대역폭을 사용하여 1.5 km 간격의 격자 해상도를 갖는다. HF Radar를 이용하여 관측한 파랑 자료는 현장에서 관측한 파랑계 자료와 비교 검증을 하였으며, 해류 자료는 국립해양조사원에서 제공한 월별 동해평균표층 해류도와 해류흐름 패턴과 비교하였다. 파랑의 비교 자료들에 대한 회귀선과의 편차는 주성분 분석(Principle Component Analysis)으로 계산하였고, 그 결과로 상관관계 0.86와 RMSD 0.186을 보였다. 또한 동해연안의 해수유동에 대한 장기간의 변화를 분석해본 결과 8월과 9월의 연안에서는 북한한류가 남쪽방향으로, 외해에서는 동한난류가 북쪽방향으로 흐르는 흐름이 나타났다.

Keywords

References

  1. D. H. Kim, C. H. Lim, H. B. Moon, H. Y. You, and S. D. Hong, "Use of HF radar for the observation of sea surface current and the present operational status" Journal of the Korean Society of Marine Engineering, vol. 35, no. 2, pp.123 - 123, 2011 (in Korean).
  2. S. M. Kim, S. O. Lee, M. K. Choi, and Y. S. Cho, "Field survey of 1983 central East Sea Tsunami : Imwon Port", Korean Society of Hazard Mitigration, vol. 7, no. 4, pp. 97-105, 2007 (in Korean).
  3. B. J. Choi, D. S. Byun, and K. H. Lee, "Satellite-altimeter-derived East Sea surface currents: Estimation, description and variability pattern" Journal of the Korean Society of Oceanography, vol. 17, no. 4, pp. 225-242, 2012 (in Korean). https://doi.org/10.7850/jkso.2012.17.4.225
  4. D. Prandle, "The fine structure of near shore tidal and residual circulations reveled by H.F. radar surface current measurements", Journal of the Physical oceanography, vol. 17, no. 2, pp. 231-245, 1987. https://doi.org/10.1175/1520-0485(1987)017<0231:TFSONT>2.0.CO;2
  5. J. D. Paduan and H. C. Graber, "Introduction to HF radar, reality and myth". oceanography, vol. 10, no. 2, pp. 36-39, 1997. https://doi.org/10.5670/oceanog.1997.18
  6. P. J. Knight and M. J. Howarth, "The flow through the northern channel of th Irish Sea". Continental Shelf Research, vol. 19, pp. 693-713, 1999. https://doi.org/10.1016/S0278-4343(98)00110-1
  7. B. K. Haus, J. D. Wang, J. Martinez-Pedraja, and N. Smith, "Remote radar measurement of shelf currents off Key Largo, Florida, USA. estuarine", Coastal and Shelf Sciences, vol. 51, no. 5, pp. 553-569, 2000. https://doi.org/10.1006/ecss.2000.0704
  8. S. H. Lee, H. B. Moon, H. Y. Baek, C. S. Kim, Y. T. Son, H. K. Kwon, and B. J. Choi, "Accuracy of HF radar-derived surface current data in the coastal waters off the Keum River estuary", Journal of the Korean Society of Oceanography, vol. 13, no. 1, pp. 42-55, 2008 (in Korean).
  9. D. E. Barrick, M. W. Evans, and B. L. Weber, "Ocean surface currents mapped by radar", Science, vol. 198, no. 4313, pp. 138-144, 1977. https://doi.org/10.1126/science.198.4313.138
  10. R. D. Chapman, L. K. Shay, H. C. Graber, J. B. Edson, A. Karachintsev, C. L. Trump, and D. B. Ross. "On the accuracy of HF radar surface current measurements: inter-comparisons with ship-based sensors", Journal of the Geophysical Research, vol. 102, no. 18, pp. 18737-18748, 1997. https://doi.org/10.1029/97JC00049
  11. Y. Yoshikawa, A. Masuda, K. Marubayashi, M. Ishibashi, and A. Okuno, "On the accuracy of HF radar measurement in the Tsushima Strait", Journal of the Geophysical Research, vol. 111, no. C04009, pp. 1-10, 2006.
  12. K. M. Song, C. H. Cho, K. T. Jung, and H. J. Lie "Report on the present condition and operating of high frequency ocean surface radars", Korean Society of Coastal and Ocean Engineers, vol. 22, no. 6, pp. 437-445, 2010 (in Korean).
  13. T. Helzel,, M. Kniephoff, and L. Petersen "Oceanography radar system WERA: features, accuracy, reliability and limitations", Turkish Journal of Electrical Engineering and Computer Science, vol. 18 no. 3, pp. 389-397, 2010.
  14. H. H. Essen, K. W. Gurgel, and T. Schlick, "On the accuracy of current measurements by means of HF radar", IEEE Journal of Oceanic Engineering, vol. 25, no. 4, pp. 472-480, 2000. https://doi.org/10.1109/48.895354
  15. Nortek As, "AWAC brochure", http://www.nortek-as.com/lib/brochures/datasheet-awac Accessed July 14, 2014.
  16. Y. Goda, "On the methodology of selecting design wave height", Proceedings 21st International Conference Coastal Engineering, pp. 899-913, 1988.