A Study on the Characteristics of Large Amplitude Ocean Waves

대진폭 해양파의 특성에 대한 연구

  • Kim, Do-Young (Department Naval Architecture and Ocean Engineering, Hongik University)
  • Published : 2009.05.25

Abstract

In this paper time series wave data which contain a freak wave is investigated. Various wave characteristics are compared between wave data with a freak wave and without. Among 24 hour wave data measured in the Yura Sea, two adjacent 30 min wave data with and without a freak wave are examined intensively. It is seen that the highest waves do not have the longest wave period. The wave period of the longest period waves is a little longer than the average wave period and much shorter than the significant wave period. Although the sea state is quite high, the Rayleigh distribution fits well to the probability of wave height. The characteristics of the wave spectra do not change much, but the nonlinearity increases for the wave data with a freak wave. The significant wave height without a freak wave is larger than that with a freak wave. Hence, the higher significant wave height does not always increase the probability of the occurrence of the freak waves.

References

  1. Kim D. Y., 1998, Wave Climate at Hong-do and Mara-do Sea Area, J. Korean Soc. for Marine Environmental Eng., Vol. 1, No 27, pp. 71-81.
  2. Mori, N., 1997, Occurrence properties of giant freak waves in Sea Area aroud Japan, J. waterway, port, coastal Engineering, July/Aug. 1997, pp. 209-213.
  3. Liu, P.C. and Pinho, U.F., 2004, Freak waves-more frequent that rare! Annales Geophysics, 22 pp. 1839-1842. https://doi.org/10.5194/angeo-22-1839-2004
  4. Mori, N., Pau, C.L. and Yasuda, T., 2002, Analysis of freak wave measurements in the Sea of Japan, Ocean Engineering 29, pp. 1399-1414. https://doi.org/10.1016/S0029-8018(01)00073-7
  5. Mori, N., 2004, Occurrence probability of a freak wave in a nonlinear wave field, Ocean Engineering 31, pp. 165-175. https://doi.org/10.1016/S0029-8018(03)00119-7
  6. Stansell, P., 2005, Distributions of extreme wave, crest and trough heights measured in the North Sea, Ocean Engineering, 32, pp. 1015-1036. https://doi.org/10.1016/j.oceaneng.2004.10.016