CHARACTERISTICS

DESCRIPTION

Identification

REFRA
Model originator : MUMM
Model operator : D. Van den Eynde

Scope

Spectral refraction model which improves the results of the Hypas model at selected stations

Conceptual background

This model takes into account the changing direction of wave energy propagation at the lower frequencies. A quasi-stationary approach is implemented. A reverse tracking of the wave rays is carried out in order to determine the modified wave energy spectra at several points of interest (along the shipping route).

The resolution is 500 m * 500 m

Inputs

The model uses the sea surface elevation predicted by OPTOS and open boundary conditions coming from the fine grid of the HYPAS model.

Geographical coverage

The model is applied on a stereographic grid. The corners are given below

Left up (2.049°W, 51.606°N)
Left down (2.098°W, 51.012°N)
Right up (3.578°O, 51.642°N)
Right down (3.602°O, 51.048°N)

Outputs

— Time series (each 3 hours) of various wave parameters at selected stations

— Wave spectra (of frequency and direction) at selected stations each 3 hours

Validation

In 1992, studies of D. Van den Eynde showed:

bias of -10.6 cm and a scatter index of 34.1 % for the significant height
bias of -0.06 s and a scatter index of 21.7 % for the mean period.

Present field of application

The model gives characteristics of refracted waves in front of the Belgian coast

Possible complementary use

The model could be used for spectral refraction calculations at the Belgian coast.

Present limitations, future needs and possible development

No atmospheric input, energy dissipation or limitation of the spectrum is taken into account.

Reference of representative publication

D. Van den Eynde, 1991. Refraktie van deiningsspektra, het rekenmodel SPECIN. MUMM report, 32 pp., 7 fig., 4 app.

D. Van den Eynde, 1992. MU-WAVE: an operational wave forecasting system for the Belgian coast. In: Proc. 3th Int. Workshop on Wave Hindcasting and Forecasting, May 19-22, 1992, Montréal, Canada, 313-324.

D. Van den Eynde, J. Berlamont en J. Monbaliu,1990. Refraktie van deiningsspektra. Water, 52, 168-172.

D. Van den Eynde, and L. Li,1990. Wave prediction at the lagune of Venice by a wave refraction model. Presented at 'VIII International Conference on Computational Methods in Water Resources', 11-15/6/1990, Venice, Italy, 22 pp.,14 fig.