Abstract
The present work focuses on the measured wave spectrum in the South China Sea (scs) during storms. The measured spectra have been obtained from surface elevation measurements undertaken at 2 locations in scs over 7 years, both of which are related to intermediate relative water depths. Shell’s stringent ts-211 quality control procedure was applied to the raw data and from the data that passed this procedure, the five largest storms for each of the locations were isolated. Analysis of this data in conjunction with the corresponding wind data confirmed that for both of the locations, the largest ‘storms’ comprised of mainly swell. In kee** with this trend, a double-peaked spectrum consisting of a Gaussian swell component and a jonswap wind component provided the best fits to the measured spectra. Further analysis of the spectral parameters resulting from the fits for the individual wave records revealed that no particular trend was identifiable for the shape parameters. Due to this, for each location, a pragmatic fit that encompasses the average spectral shape parameters obtained from all the sea states has been suggested as a typical design spectrum for each location.
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References
Amurol Jamal S, Ewans K, Sheikh R, et al. (2014) Measured wave spectra offshore Sabah & Sarawak, Malaysia. In: Offshore technology conference-Asia. Offshore technology conference
Anokhin A, Randell D, Ross E, Jonathan P (2019) Spatial and seasonal variability of metocean design criteria in the Southern South China Sea from covariate extreme value analysis. ASME
Bretschneider CL (1969) Wave variability and wave spectra for wind-generated waves. Tech. Rep. 118, Beach erosion board corps of engineers
Christou M, Ewans K (2014) Field measurements of rogue water waves. J Phys Oceanogr 44(9):2317–2335
Ewans K, Bitner-Gregersen E, Soares CG (2006) Estimation of wind-sea and swell components in a bimodal sea state. J Offshore Mech Arct Eng 128(4):265–270
Ewans K, Feld G, Jonathan P (2014) On wave radar measurement. Ocean Dyn 64(9):1281–1303. https://doi.org/10.1007/s10236-014-0742-5
Guedes-Soares C (1984) Representation of double-peaked sea wave spectra. Ocean Eng 11(2):185–207. https://doi.org/10.1016/0029-8018(84)90019-2
Guedes Soares C, Henriques A (1998) Fitting a double-peak spectral model to measured wave spectra. In: Proceedings of the 17th international conference on offshore mechanics and arctic engineering, pp 5–9
Hasselmann K, Barnett TP, Bouws E, Carlson H, Cartwright DE, Enke K, Ewing JA, Gienapp H, Hasselmann DE, Kruseman P, Meerburg A, Muller P, Olbers DJ, Richter K, Sell W, Walden H (1973) Measurements of wind-wave growth and swell decay during the joint north sea wave project (jonswap).Tech. Rep. A12, Ergnzungsheft zur Deutschen Hydrographischen Zeitschrift Reihe
ISO 19901-1 (2005) Petroleum and natural gas industries-specific requirements for offshore structures-part 1: metocean design and operating conditions. ISO
Lucas C, Soares CG (2015) On the modelling of swell spectra. Ocean Eng 108:749–759
Ochi MK, Hubble EN (1976) Six parameter wave spectra. In: Proceedings of the 15th conference on coastal engineering, pp 301–328
Pierson WJJ, Moskowitz L (1964) A proposed spectral form for fully developed wind seas based on the similarity theory of s. a. kitaigorodskii. J Geophys Res 69:5181–5190. https://doi.org/10.1029/JZ069i024p05181
PTS 34.19.10.30 (2012) Petronas technical standards: Design of fixed offshore structures (working stress design). PTS
Soares CG (1991) On the occurence of double peaked wave spectra. Ocean Eng 18(1-2):167–171
Torsethaugen K, Haver S (2004) Simplified double peak spectral model for ocean waves. In: Proceedings of the 14th ISOPE conference. International society offshore polar engineering
Welch P (1967) The use of fast fourier transform for the estimation of power spectra: a method based on time averaging over short, modified periodograms. IEEE Trans Audio Electroacoust 15(2):70–73
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The authors would like to acknowledge the corrections and further suggestions made by the anonymous reviewers that greatly improved the final manuscript.
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This research is funded by yutp grant no. 0513aa-e86.
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Latheef, M., Abdullah, M.N. & Jupri, M.F.M. Observed spectrum in the South China Sea during storms. Ocean Dynamics 70, 353–364 (2020). https://doi.org/10.1007/s10236-019-01332-9
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DOI: https://doi.org/10.1007/s10236-019-01332-9