English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Measurements of wind-wave growth and swell decay during the joint North Sea wave project (JONSWAP).

Hasselmann, K. F., Barnett, T., Bouws, E., Carlson, H., Cartwright, D., Eake, K., et al. (1973). Measurements of wind-wave growth and swell decay during the joint North Sea wave project (JONSWAP). Ergänzungsheft zur Deutschen Hydrographischen Zeitschrift, Reihe A, Nr. 12.

Item is

Basic

show hide
Genre: Journal Article

Files

show Files
hide Files
:
1973_Jonswap-Hasselmann1973.pdf (Publisher version), 6MB
Name:
1973_Jonswap-Hasselmann1973.pdf
Description:
Scan des Volltextes
Visibility:
Public
MIME-Type / Checksum:
application/pdf / [MD5]
Technical Metadata:
Copyright Date:
-
Copyright Info:
© The authors
License:
-

Locators

show

Creators

show
hide
 Creators:
Hasselmann, Klaus F.1, Author              
Barnett, T.P., Author
Bouws, E., Author
Carlson, H., Author
Cartwright, D.E., Author
Eake, K., Author
Euring, J.A., Author
Gicnapp, A., Author
Hasselmann, D.E., Author
Kruseman, P., Author
Meerburg, A., Author
Mullen, P., Author
Olbers, D.J., Author
Richren, K., Author
Sell, W., Author
Walden, H., Author
Affiliations:
1Institut für Geophysik, Universität Hamburg, ou_persistent22              

Content

show
hide
Free keywords: -
 Abstract: Wavo spectra were measured along a profile extending 160 km into the North Sea westward from Sylt for a period of ten weeks in 1969. Currents, tides, air-sea temperature differences and turbulence in the atmospheric boundary layer were also measured. the goal of the experiment (described in Part 1) was to determine the structure of the source function governing the energy balance of the wave spectrum, with particular emphasis on wave growth under stationary offshore wind conditions (Part 2) and the attention of swell in water of finito depth (Part 3). The source functions of wave spectra generated by offshore winds exhibit a characteristic plus-minus signature associated with the shift of the sharp spectral peak towards lower frequencies. The two-lobed distribution of the source function can be explained quantitively by the nonlinear transfer due to resonant wave-wave interactions (second order Bragg scattering). The evolution of a pronounced peak and its shift towards lower frequencies can also be understood as a self-stabilizing feature of this process. The decay rates determined for incoming swell varied considerably, but energy attenuation factors of two along the length of the profile were typical. This is in order of magnitude agreement with expected damping rates due to bottom friction. However, the strong tidal modulation predicted by theory for the case of a quadratic bottom friction law was not observed. Adverse winds did not affect the decay rate. Computations also rule out wave-wave interactions or dissipation due to turbulence outside the bottom boundary layer as effective mechanisms of swell attenuation. We conclude that either the generally accepted friction law needs to be significantly modified or that some other mechanism, such as scattering by bottom irregularities, is the cause of the attenuation. The dispersion characteristics of thw swells indicated rather nearby origins, for which the classical DELTA-event model was generally inapplicable. A strong Doppler modulation by tidal currents was also observed. (A)

Details

show
hide
Language(s): eng - English
 Dates: 1973
 Publication Status: Published in print
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Type: Peer
 Identifiers: BibTex Citekey: Hasselmann1973
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Ergänzungsheft zur Deutschen Hydrographischen Zeitschrift, Reihe A
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: -
Pages: - Volume / Issue: Nr. 12 Sequence Number: - Start / End Page: - Identifier: -