Swell and slanting-fetch effects on wind wave growth

Fabrice Ardhuin, T. H C Herbers, Gerbrant Ph van Vledder, Kristen P. Watts, R. Jensen, Hans C Graber

Research output: Contribution to journalArticle

82 Citations (Scopus)

Abstract

Wind-sea generation was observed during two experiments off the coast of North Carolina. One event with offshore winds of 9-11 m s-1 directed 20° from shore normal was observed with eight directional stations recording simultaneously and spanning a fetch from 4 to 83 km. An opposing swell of 1-m height and 10-s period was also present. The wind-sea part of the wave spectrum conforms to established growth curves for significant wave height and peak period, except at inner-shelf stations where a large alongshore wind-sea component was observed. At these short fetches, the mean wave direction θm was observed to change abruptly across the wind-sea spectral peak, from alongshore at lower frequencies to downwind at higher frequencies. Waves from another event with offshore winds of 6-14 m s-1 directed 20°-30° from shore normal were observed with two instrument arrays. A significant amount of low-frequency wave energy was observed to propagate alongshore from the region where the wind was strongest. These measurements are used to assess the performance of some widely used parameterizations in wave models. The modeled transition of θm across the wind-sea spectrum is smoother than that in the observations and is reproduced very differently by different parameterizations, giving insights into the appropriate level of dissipation. Calculations with the full Boltzmann integral of quarter wave-wave interactions reveal that the discrete interaction approximation parameterization for these interactions is reasonably accurate at the peak of the wind sea but overpredicts the directional spread at high frequencies. This error is well compensated by parameterizations of the wind input source term that have a narrow directional distribution. Observations also highlight deficiencies in some parameterizations of wave dissipation processes in mixed swell-wind-sea conditions.

Original languageEnglish (US)
Pages (from-to)908-931
Number of pages24
JournalJ. PHYSICAL OCEANOGRAPHY
Volume37
Issue number4
DOIs
StatePublished - Apr 2007

Fingerprint

fetch
wind wave
swell
parameterization
dissipation
effect
wave-wave interaction
wave direction
significant wave height
growth curve
wave spectrum
sea
wave energy

ASJC Scopus subject areas

  • Oceanography

Cite this

Ardhuin, F., Herbers, T. H. C., van Vledder, G. P., Watts, K. P., Jensen, R., & Graber, H. C. (2007). Swell and slanting-fetch effects on wind wave growth. J. PHYSICAL OCEANOGRAPHY, 37(4), 908-931. https://doi.org/10.1175/JPO3039.1

Swell and slanting-fetch effects on wind wave growth. / Ardhuin, Fabrice; Herbers, T. H C; van Vledder, Gerbrant Ph; Watts, Kristen P.; Jensen, R.; Graber, Hans C.

In: J. PHYSICAL OCEANOGRAPHY, Vol. 37, No. 4, 04.2007, p. 908-931.

Research output: Contribution to journalArticle

Ardhuin, F, Herbers, THC, van Vledder, GP, Watts, KP, Jensen, R & Graber, HC 2007, 'Swell and slanting-fetch effects on wind wave growth', J. PHYSICAL OCEANOGRAPHY, vol. 37, no. 4, pp. 908-931. https://doi.org/10.1175/JPO3039.1
Ardhuin F, Herbers THC, van Vledder GP, Watts KP, Jensen R, Graber HC. Swell and slanting-fetch effects on wind wave growth. J. PHYSICAL OCEANOGRAPHY. 2007 Apr;37(4):908-931. https://doi.org/10.1175/JPO3039.1
Ardhuin, Fabrice ; Herbers, T. H C ; van Vledder, Gerbrant Ph ; Watts, Kristen P. ; Jensen, R. ; Graber, Hans C. / Swell and slanting-fetch effects on wind wave growth. In: J. PHYSICAL OCEANOGRAPHY. 2007 ; Vol. 37, No. 4. pp. 908-931.
@article{cc5c6b8763fb49ba906bdb9257e95bb0,
title = "Swell and slanting-fetch effects on wind wave growth",
abstract = "Wind-sea generation was observed during two experiments off the coast of North Carolina. One event with offshore winds of 9-11 m s-1 directed 20° from shore normal was observed with eight directional stations recording simultaneously and spanning a fetch from 4 to 83 km. An opposing swell of 1-m height and 10-s period was also present. The wind-sea part of the wave spectrum conforms to established growth curves for significant wave height and peak period, except at inner-shelf stations where a large alongshore wind-sea component was observed. At these short fetches, the mean wave direction θm was observed to change abruptly across the wind-sea spectral peak, from alongshore at lower frequencies to downwind at higher frequencies. Waves from another event with offshore winds of 6-14 m s-1 directed 20°-30° from shore normal were observed with two instrument arrays. A significant amount of low-frequency wave energy was observed to propagate alongshore from the region where the wind was strongest. These measurements are used to assess the performance of some widely used parameterizations in wave models. The modeled transition of θm across the wind-sea spectrum is smoother than that in the observations and is reproduced very differently by different parameterizations, giving insights into the appropriate level of dissipation. Calculations with the full Boltzmann integral of quarter wave-wave interactions reveal that the discrete interaction approximation parameterization for these interactions is reasonably accurate at the peak of the wind sea but overpredicts the directional spread at high frequencies. This error is well compensated by parameterizations of the wind input source term that have a narrow directional distribution. Observations also highlight deficiencies in some parameterizations of wave dissipation processes in mixed swell-wind-sea conditions.",
author = "Fabrice Ardhuin and Herbers, {T. H C} and {van Vledder}, {Gerbrant Ph} and Watts, {Kristen P.} and R. Jensen and Graber, {Hans C}",
year = "2007",
month = "4",
doi = "10.1175/JPO3039.1",
language = "English (US)",
volume = "37",
pages = "908--931",
journal = "Journal of Physical Oceanography",
issn = "0022-3670",
publisher = "American Meteorological Society",
number = "4",

}

TY - JOUR

T1 - Swell and slanting-fetch effects on wind wave growth

AU - Ardhuin, Fabrice

AU - Herbers, T. H C

AU - van Vledder, Gerbrant Ph

AU - Watts, Kristen P.

AU - Jensen, R.

AU - Graber, Hans C

PY - 2007/4

Y1 - 2007/4

N2 - Wind-sea generation was observed during two experiments off the coast of North Carolina. One event with offshore winds of 9-11 m s-1 directed 20° from shore normal was observed with eight directional stations recording simultaneously and spanning a fetch from 4 to 83 km. An opposing swell of 1-m height and 10-s period was also present. The wind-sea part of the wave spectrum conforms to established growth curves for significant wave height and peak period, except at inner-shelf stations where a large alongshore wind-sea component was observed. At these short fetches, the mean wave direction θm was observed to change abruptly across the wind-sea spectral peak, from alongshore at lower frequencies to downwind at higher frequencies. Waves from another event with offshore winds of 6-14 m s-1 directed 20°-30° from shore normal were observed with two instrument arrays. A significant amount of low-frequency wave energy was observed to propagate alongshore from the region where the wind was strongest. These measurements are used to assess the performance of some widely used parameterizations in wave models. The modeled transition of θm across the wind-sea spectrum is smoother than that in the observations and is reproduced very differently by different parameterizations, giving insights into the appropriate level of dissipation. Calculations with the full Boltzmann integral of quarter wave-wave interactions reveal that the discrete interaction approximation parameterization for these interactions is reasonably accurate at the peak of the wind sea but overpredicts the directional spread at high frequencies. This error is well compensated by parameterizations of the wind input source term that have a narrow directional distribution. Observations also highlight deficiencies in some parameterizations of wave dissipation processes in mixed swell-wind-sea conditions.

AB - Wind-sea generation was observed during two experiments off the coast of North Carolina. One event with offshore winds of 9-11 m s-1 directed 20° from shore normal was observed with eight directional stations recording simultaneously and spanning a fetch from 4 to 83 km. An opposing swell of 1-m height and 10-s period was also present. The wind-sea part of the wave spectrum conforms to established growth curves for significant wave height and peak period, except at inner-shelf stations where a large alongshore wind-sea component was observed. At these short fetches, the mean wave direction θm was observed to change abruptly across the wind-sea spectral peak, from alongshore at lower frequencies to downwind at higher frequencies. Waves from another event with offshore winds of 6-14 m s-1 directed 20°-30° from shore normal were observed with two instrument arrays. A significant amount of low-frequency wave energy was observed to propagate alongshore from the region where the wind was strongest. These measurements are used to assess the performance of some widely used parameterizations in wave models. The modeled transition of θm across the wind-sea spectrum is smoother than that in the observations and is reproduced very differently by different parameterizations, giving insights into the appropriate level of dissipation. Calculations with the full Boltzmann integral of quarter wave-wave interactions reveal that the discrete interaction approximation parameterization for these interactions is reasonably accurate at the peak of the wind sea but overpredicts the directional spread at high frequencies. This error is well compensated by parameterizations of the wind input source term that have a narrow directional distribution. Observations also highlight deficiencies in some parameterizations of wave dissipation processes in mixed swell-wind-sea conditions.

UR - http://www.scopus.com/inward/record.url?scp=34249072805&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34249072805&partnerID=8YFLogxK

U2 - 10.1175/JPO3039.1

DO - 10.1175/JPO3039.1

M3 - Article

AN - SCOPUS:34249072805

VL - 37

SP - 908

EP - 931

JO - Journal of Physical Oceanography

JF - Journal of Physical Oceanography

SN - 0022-3670

IS - 4

ER -