do Instituto Hidrográfico

PRE-PROCESSING AND POST-PROCESSING OF MODEL WAVE DATA IN THE NEARSHORE 73
0.4 , j 3 # 0.4 – spilling;
0.4 , j 3 # 2.4 – plunging;
2.4 , j 3 # 2.6 – plunging / collap sin g; (6)
2.6 , j 3 # 3.1 – collap sin g / surging;
2.4 , j 3 . 3.1 – surging.
There were used also in this module some results from
the linear theory for estimating the breaking ratio and
the number of wave fronts in the surf [Soares et al 2000].
4.5 Options for cumulative and parallel
data analysis
Besides the capacity of this new designed nowcasting
tool to process and present graphically (and numerically),
data concerning a specific moment of the sea
state in the considered area, it was created also the
possibility for the user to make a time evolution analyze
of the wave parameters. Consequently although most of
the variables are reinitialized any time when is changed
the case, some other variables are loaded as global
vectors, which perpetuates and extend their dimension
in each case analyzed. In this way ‘TOTAL WAVE’ can be
used not only for studying the distribution in space at
one instant of the wave variables, but also to visualize
their time evolution and to design automatically some
forecast products. Another new option is the parallel
analysis that can be done with different windows either
in terms of spatial or temporal variations.
5. Some concluding remarks
High-resolution numerical wave models, being able
to generate forecast products of the oceanographic data,
are nowadays utilized more and more, to provide in a
near real time scale the environmental support for
significant areas. This concerns especially the coastal
environment where the influence of the nonlinear
effects is much higher than in the offshore areas.
However, while the general research was focused in
developing the physics of the spectral phase averaged
models by improving the nonlinear source terms, there
is still a strong need of easy to use interfaces for an
adequate pre-processing and post-processing of the
data. With this motivation the goal of the present work
was to develop a new pre-processing tool for the coastal
environment ‘BARCO’, with graphical and numerical
outputs, which would be used in correlation with an
advanced version of an already developed post-processing
nowcast tool ‘TOTAL WAVE’. Because of its high
performances in integration between computations and
visualization effects was used the MATLAB environment.
Moreover both the data import and the actions control
were performed using the UI-commands. The data files
were introduced into the system by commands of the
type ‘UIGETFILE’ while the global variables by ‘EDIT
BOXES’. In the same time the simulations were initiated
usually by ‘UI-MENU’ commands and the actions
inside a simulation are controlled by ‘PUSH BUTTONS’,
following in this way the MATLAB internal hierarchy.
The two programs were applied successfully
together with the SWAN model, but they could be also
useful in conjunction with most of the existent wave
models. There were made available, in a user-friendly
way, graphical and numerical outputs for the main wave
parameters in the nearshore. Moreover using the results
of the linear theory where evaluated the characteristics
of the breaking process. There are some important
benefits brought by the tools developed herewith. First
in this way can be made a better selection of the area
where is going to be run the model. Then is a drastically
decreasing of the computational time of the model
because of the reduced number of the output requests.
Fig. 17 – Spctral analysis Fig. 18 – Surf-zone conditions