Estimation of Directional Wave Spectra from HF Radar Sea Echo Doppler Spectra

Shoichiro Kojima, Noriaki Hashimoto, Yuji Sato

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Citations (Scopus)

Abstract

The use of oceanic radar to measure currents at the sea's surface has become practicable. Many observations of currents in coastal zones have, in fact, provided quite worthwhile results. In contrast to this, the measurement of ocean waves by oceanic radar is still at the theoretical level. Bayesian estimation may be applied to obtain directional wave spectra from Doppler spectra. This method is, in theory, applicable, but noise contaminates the measured Doppler spectra so that they deviate significantly from the ideal. Bayesian estimation relies solely on second-order backscattering components, yet accurate estimation of directional wave spectra from observed Doppler spectra requires the proper separation of the first- and second-order backscattering components of the Doppler spectra; this is a difficult task because of the great variety of observed Doppler spectra. A method where we apply wavelet multiple-resolution analysis to separate out the first- and second-order backscattering components of the spectra is discussed. In addition, a new method where we apply both the first- and second-order backscattering components to obtain directional wave spectra that have better resolution is described. Finally, HF oceanic-radar facilities along the Kashima coast were used to conduct a series of field measurements of Doppler spectra, from which the directional wave spectra were then estimated. Simultaneous observations were made with a wave-gage array, and subsequent comparison showed good agreement with the results obtained from the HF oceanic radar observations.

Original languageEnglish
Title of host publicationProceedings of the 28th International Conference on Coastal Engineering 2002
Subtitle of host publicationSolving Coastal Conundrums, ICCE 2002
EditorsJane McKee Smith
PublisherAmerican Society of Civil Engineers (ASCE)
Pages109-120
Number of pages12
ISBN (Electronic)9812382380, 9789812382382
DOIs
Publication statusPublished - Jan 1 2003
Externally publishedYes
Event28th International Conference on Coastal Engineering, ICCE 2002 - Cardiff, Wales, United Kingdom
Duration: Jul 7 2002Jul 12 2002

Publication series

NameProceedings of the Coastal Engineering Conference
Volume2003-January
ISSN (Print)0161-3782

Other

Other28th International Conference on Coastal Engineering, ICCE 2002
CountryUnited Kingdom
CityCardiff, Wales
Period7/7/027/12/02

Fingerprint

wave spectrum
Backscattering
Radar
radar
Coastal zones
Water waves
Gages
ocean wave
sea
wavelet
coastal zone
gauge
sea surface
coast
method

All Science Journal Classification (ASJC) codes

  • Civil and Structural Engineering
  • Ocean Engineering
  • Oceanography

Cite this

Kojima, S., Hashimoto, N., & Sato, Y. (2003). Estimation of Directional Wave Spectra from HF Radar Sea Echo Doppler Spectra. In J. M. Smith (Ed.), Proceedings of the 28th International Conference on Coastal Engineering 2002: Solving Coastal Conundrums, ICCE 2002 (pp. 109-120). (Proceedings of the Coastal Engineering Conference; Vol. 2003-January). American Society of Civil Engineers (ASCE). https://doi.org/10.1142/9789812791306_0010

Estimation of Directional Wave Spectra from HF Radar Sea Echo Doppler Spectra. / Kojima, Shoichiro; Hashimoto, Noriaki; Sato, Yuji.

Proceedings of the 28th International Conference on Coastal Engineering 2002: Solving Coastal Conundrums, ICCE 2002. ed. / Jane McKee Smith. American Society of Civil Engineers (ASCE), 2003. p. 109-120 (Proceedings of the Coastal Engineering Conference; Vol. 2003-January).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Kojima, S, Hashimoto, N & Sato, Y 2003, Estimation of Directional Wave Spectra from HF Radar Sea Echo Doppler Spectra. in JM Smith (ed.), Proceedings of the 28th International Conference on Coastal Engineering 2002: Solving Coastal Conundrums, ICCE 2002. Proceedings of the Coastal Engineering Conference, vol. 2003-January, American Society of Civil Engineers (ASCE), pp. 109-120, 28th International Conference on Coastal Engineering, ICCE 2002, Cardiff, Wales, United Kingdom, 7/7/02. https://doi.org/10.1142/9789812791306_0010
Kojima S, Hashimoto N, Sato Y. Estimation of Directional Wave Spectra from HF Radar Sea Echo Doppler Spectra. In Smith JM, editor, Proceedings of the 28th International Conference on Coastal Engineering 2002: Solving Coastal Conundrums, ICCE 2002. American Society of Civil Engineers (ASCE). 2003. p. 109-120. (Proceedings of the Coastal Engineering Conference). https://doi.org/10.1142/9789812791306_0010
Kojima, Shoichiro ; Hashimoto, Noriaki ; Sato, Yuji. / Estimation of Directional Wave Spectra from HF Radar Sea Echo Doppler Spectra. Proceedings of the 28th International Conference on Coastal Engineering 2002: Solving Coastal Conundrums, ICCE 2002. editor / Jane McKee Smith. American Society of Civil Engineers (ASCE), 2003. pp. 109-120 (Proceedings of the Coastal Engineering Conference).
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