Spectral characteristics of high shallow water waves

Abstract The spectral characteristics of shallow water waves with significant wave height more than 2 m based on the data collected along the Indian coast is examined. It was found that the value of Joint North Sea Wave Project (JONSWAP) parameters ( α and γ ) increases with significant wave height and mean wave period and decreases with spectral peak period. The estimated average value (0.0027 and 1.63) of the JONSWAP parameters, α and γ were less than the generally recommended values of 0.0081 and 3.3, respectively. By carrying out a multi-regression analysis, an empirical equation is arrived relating the JONSWAP parameters with significant wave height, peak wave period and mean wave period. It was found that the Scott spectra underestimate the maximum spectral energy of high waves. The study shows that the measured wave spectra can be represented by JONSWAP spectra with the JONSWAP parameters estimated based on the equation proposed in this paper.

[1]  E. Nadine Hubble,et al.  Six-Parameter Wave Spectra , 1976 .

[2]  S. Mandal,et al.  Multipeakedness and groupiness of shallow water waves along Indian coast , 2003 .

[3]  I. Young,et al.  Observations of the spectra of hurricane generated waves , 1998 .

[4]  The determination of spectral parameters from significant wave height and peak period , 1992 .

[5]  J. Labeyrie,et al.  Time scales and statistical uncertainties in the prediction of extreme environmental conditions , 1991 .

[6]  M. J. Tucker,et al.  Interpreting directional data from large pitch-roll-heave buoys , 1989 .

[7]  A. Babanin,et al.  Field Investigation of Transformation of the Wind Wave Frequency Spectrum with Fetch and the Stage of Development , 1998 .

[8]  M. Donelan,et al.  Directional spectra of wind-generated ocean waves , 1985, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

[9]  J. R. Scott,et al.  A Sea Spectrum for Model Tests and Long-Term Ship Prediction , 1965 .

[10]  T. Barnett,et al.  Measurements of wind-wave growth and swell decay during the Joint North Sea Wave Project (JONSWAP) , 1973 .

[11]  Wolfgang Rosenthal,et al.  Similarity of the wind wave spectrum in finite depth water part 2: Statistical relations between shape and growth stage parameters , 1985 .

[12]  W. Pierson,et al.  A proposed spectral form for fully developed wind seas based on the similarity theory of S , 1964 .

[13]  W. Rosenthal,et al.  Similarity of the wind wave spectrum in finite depth water: 1. Spectral form , 1985 .

[14]  J. Darbyshire.  A further investigation of wind generated waves , 1959 .

[15]  Design wave estimation considering directional distribution of waves , 2004 .

[16]  Michel K. Ochi,et al.  Hurricane-generated seas , 1994 .

[17]  I. Young,et al.  A review of the sea state generated by hurricanes , 2003 .

[18]  Makarand Deo,et al.  Spectral Analysis of Ocean Waves — A Study , 1979 .

[19]  S. Shetye,et al.  Impact of sea breeze on wind-seas off Goa, west coast of India , 2006 .

[20]  Harihara Raman,et al.  Comparison of Scott Spectra with Ocean Wave Spectra , 1977 .

[21]  S. A. Kitaigordskii,et al.  On Phillips' Theory of Equilibrium Range in the Spectra of Wind-Generated Gravity Waves , 1975 .

[22]  S F Barstow,et al.  Field Trials Of The Directional Waverider , 1991 .

[23]  V. Sanil Kumar,et al.  Variations in wave direction estimated using first and second order Fourier coefficients , 2004 .

[24]  M. Baba,et al.  On spectral and statistical characteristics of shallow water waves , 1986 .

[25]  I. Young,et al.  The growth of fetch limited waves in water of finite depth. Part 2. Spectral evolution , 1996 .

[26]  Subrata K. Chakrabarti,et al.  Handbook of Offshore Engineering , 2005 .