1. SWAN model applications
Projects/Sandy

2. Outline SWAN model application overview
How to create a SWAN only application
How to create a SWAN coupled application

3. SWAN N = wave action density (energy density / relative frequency)
cx, cy = propagation velocities (x- and y- directions)
s = relative frequency
= wave direction
S = source/sink term for:
- wind-wave generation
- wave breaking
- bottom dissipation
- nonlinear wave-wave interactions
SWAN accounts for shoaling, diffraction, partial transmission, and reflection.
Booij, N., R.C. Ris and L.H. Holthuijsen, 1999, A third-generation wave model for coastal regions, Part I, Model description and validation,
J.Geoph.Research, 104, C4,
Booij, N., R.C. Ris and L.H. Holthuijsen, 1999, A third-generation wave model for coastal regions, Part II, Model description and validation,
Booij, N., Haagsma, IJ.G., Holthuijsen, L.H., Kieftenburg, A.T.M.M., Ris, R.C., van der Westhuysen, A.J., and Zijlema, M. (2004).
SWAN Cycle III version User Manual, Delft University of Technology.

4. SWAN User's manual

5. SWAN grid points ROMS grid
For the SWAN grid, we set the SWAN points on the ROMS rho points.
eta xi
Borrowed from Marcel’s presentation

6. SWAN grid tiling SWAN ROMS
SWAN tiles the grid by dividing the longest side into multiple sections.
Don’t have any tiles that are all land mask. This may not work with the way we require the entire SWAN grid to be accounted for in the exchanges.

7. SWAN is driven by a series of 'KEYWORDS' in the input file.
To run SWAN - Input file
SWAN is driven by a series of 'KEYWORDS' in the input file.
'PROJECT'
'MODE'
'SET'
'CGRID'
'READGRID'
etc
Projects/Inlet_Test/Swanonly/swan_inlet_test.in

8. Keywords: Start-up

9. Keywords: model description

10. Keywords: model description

11. Keywords: Output and Run

12. How to create a SWAN only application
1) grids
2) wind forcing
3) boundary conditions
4) cppdefs.h
5) coawst.bash
6) INPUT
7) run it – to create init files
8) INPUT
9) run it – to run for multiday
These steps are in the Projects/Sandy/create_sandy_application.m

13. 1) Grids There are several ways to make a SWAN computational grid.
you can use the CGRID Regular command in the SWAN INPUT file. This is for a regular grid, even spacings, perhaps on an angle. or
2) If you already have a ROMS grid then run
COAWST/Tools/mfiles/mtools/
roms2swan(lon_rho(or x), lat_rho (or y), depth, mask)
This creates 2 files:
grid_coord.grd (goes with READGRID COORDS)
swan_bathy.bot (goes with READINP BOTTOM)

14. SWAN Grids for Sandy

15. 2) wind forcing
Can use Tools\mfiles\mtools\nam_narr_2swan.m

16. 2) wind forcing
Can use Tools\mfiles\mtools\nam_narr_2swan.m

17. Create SWAN wind forcing for Sandy

18. 3) boundary conditions - TPAR
Can use Tools\mfiles\swan_forc\ww3_swan_input.m
First, acquire the necessary grib files from
ftp://polar.ncep.noaa.gov/pub/history/waves/
Then run this script to read WW3 model output and create SWAN TPAR boundary forcing files.
The m files creates some commands lines called "BOUNDSPEC." You must copy the command lines from the file Bound_spec_command and place them into your SWAN INPUT file, such as swan_sandy.in. This is only done for the parent grid.

19. Create SWAN TPAR boundary for Sandy

20. 4) Projects/sandy.h
Just define SWAN model and for this application we have a nested grid.

21. 5) coawst.bash
Set application, project dir, and compiler options.

22. 6) Input file - control commands
Proejcts/Sandy/swan_sandy.in
PROJECT - 4 text lines
MODE NONSTAT TWOD
SET - DEPMIN to be same as Dcrit
- INRHOG 1 !!!!
- NAUTICAL !!!!
COORDINATES - SPHERICAL
or CARTESIAN
NSGRIDS - required
Next slides

23. Input file – CGRID and READGRID
CGRID and READGRID: Defines the computational grid in x, y, freq, and theta space.

24. Input file – INPGRID and READINP
INPGRID and READINP: Input grid for variables of bottom, waterlevel, currents, winds, etc.
This is for the
BOTTOM (bathymetry)

25. Input file - INPgrid
INPGRID and READINP: Input grid for other variables of [bottom], waterlevel, currents, winds, etc.
These INPGRID commands create a varying grid for that field in SWAN. Since we are not reading in any values with a READINP command, and not coupling to ROMS, they will not be used.

26. Input file – INPgrid for WIND
INPGRID and READINP: Input grid for other variables of [bottom], waterlevel, currents, winds, etc.
This WIND INPGRID command creates a wind grid for SWAN. The READINP command reads wind from a file.

27. Input file - INPgrid for WIND
INPGRID and READINP: Input grid for other variables of [bottom], waterlevel, currents, winds, etc.
Look at the nam_narr_2swan.m
for times and
grid location.

28. Input file - Boundary inputs
BOUND SHAPE
BOUND SIDE or BOUND SEGMENT
From ww3_swan_input.m

29. Lists the date, Hsig, Period, Direction, and Spreading factor
TPAR file
Lists the date, Hsig, Period, Direction, and Spreading factor

30. Input file - Init files Can start SWAN with data from an init file.
This file can be created from a STATIONARY run.
We are going to create the init files, so just set it as INIT.

31. Input file - Physics

32. Input file - Output and run
- Ouputs
- Restart : COAWST specific command to create restarts during run.
- COMPUTE – do a stationary run now to get init files.
HOTFILE – output files at end of run to use as init files.
STOP – we are done.

33. Input file for refined grid
Need to create the swan_ref3 input files also.
This is basically the same as the parent grid but:
Different grid size
NO TPAR files.
- Different names for Output files.

34. 7) run coawst Run it by pointing to the 2 SWAN input files:
mpirun -np X ./coawstM
Projects/Inlet_test/Swanonly/swan_inlet_test.in
Projects/Inlet_test/Swanonly/swan_inlet_test_ref5.in
This created the SWAN init files.

35. 8) INPUT files for multiday simulation
Point to new INIT file
Change run times
Also for refined grid input file.

36. 9) run coawst Run it by pointing to the 2 SWAN input files:
mpirun -np X ./coawstM
Projects/Inlet_test/Swanonly/swan_inlet_test.in
Projects/Inlet_test/Swanonly/swan_inlet_test_ref5.in
This created the multiday SWAN ouput.

37. SWAN Coupling
Interactions to ocean and atm models.

38. Setting up a coupled application: Projects/Sandy
WRF
SWAN
ROMS
PSFC (mb)
Hsig (m)
SST (C)