1. SWAN User's manual

2. Input file - to run SWAN by itself
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

3. Keywords: Start-up

4. Keywords: model description

5. Keywords: model description

6. Keywords: Output and Run

7. Input file - control commands
PROJECT - 4 text lines
MODE NONSTAT TWOD
SET - DEPMIN to be same as Dcrit
- INRHOG 1 !!!!!!
- NAUTICAL !!!!
COORDINATES - SPHERICAL
or CARTESIAN

8. Input file - NESTING && Need to set keyword for number of swan grids
NSGRIDS 2

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

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

11. Input file - to run SWAN by itself
INPGRID and READINP: Input grid for variables of bottom, waterlevel, currents, winds, etc.
This is an example for WIND
We typically use IDLA = 4

12. Input file - Boundary inputs
BOUND SHAPE
BOUND SIDE or BOUND SEGMENT

13. Input file - Boundary inputs
BOUND SHAPE
BOUND SIDE or BOUND SEGMENT
THIS command uses I J indices along a segment

14. Input file - Boundary inputs
BOUND SHAPE
BOUND SIDE or BOUND SEGMENT
THIS command uses X Y indices along a segment
with input files

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

16. Input file - Init files Can start SWAN with data from an init file.
This file can be created from a STATIONARY run.

17. Input file - Physics

18. Input file - Output and run
start dt end
Can make this as STATIONARY, then don’t need start:dt:end
to get init conditions files.

19. How to create a SWAN application “Sandy”
1) cppdefs.h
2) grids
3) wind forcing
4) boundary conditions
5) INPUT
6) initial conditions
7) coawst.bash
8) run it

20. 1) cppdefs.h
define to use
SWAN MODEL

21. 2) grids Parent To create swan grid from a roms grid use the m file:
roms2swan('Sandy_roms_grid.nc')
This created swan_coord.grd and swan_bathy.bot
Rename them to be
Sandy_swan_bathy.bot
Sandy_swan_coord.grd
Child
roms2swan('Sandy_roms_grid_ref3.nc')
to create swan_coord.grd and swan_bathy.bot and renamed them to:
Sandy_swan_bathy_ref3.bot
Sandy_swan_coord_ref3.grd

22. 3) wind forcing
To create a wind forcing file you need to get wind data, such as from
ftp://ftp.cdc.noaa.gov/Datasets/NARR/monolevel/
and get (for example)
uwnd.10m.2012.nc and
vwnd.10m.2012.nc
then run the m file:
narr2romsnc
Need to do this twice.

23. 4) boundary conditions - TPAR
% Acquire the necessary grib files
[hs, tp, and dp] from
ftp://polar.ncep.noaa.gov/pub/history/waves/
multi_1.at_10m.tp grb2
multi_1.at_10m.hs grb2
multi_1.at_10m.dp grb2
then run the m file
ww3_swan_input.m

24. 4) boundary conditions - TPAR
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.
This is only done for the parent grid.

25. 5) INPUT for parent

26. 5) INPUT for parent cont’d

27. 5) INPUT for parent cont’d
This is set up to run in stationary mode to get initial conditions.

28. Don’t need any boundary files
5) INPUT for child
Child wind file
Don’t need any boundary files

29. 5) INPUT for child Use same physics as for parent Output :
use different file names!
This is set up to run in stationary mode to get initial conditions.

30. 6) initial conditions
To create an init file for swan, you can run SWAN in stationary mode
and create a ‘hot start’ file(s).
This is set up to run in stationary mode to get initial conditions.
This is set up to run in Nonstationary mode to get a full simulation period.

31. 7) coawst.bash 8) run it
Build it by setting the Project name and paths in the coawst.bash.
Run it by call to coawstM,
but now need to explicitly state input file names
mpirun -np X ./coawstM
Projects/Sandy/swan_sandy.in
Projects/Sandy/swan_sandy_ref3.in
(all this is one continuous text with spaces)

32. While running ….
SWAN creates multiple mat files, these get pulled together at the end.
You can see both grids time stepping

33. Sandy wave heights
Parent only
Parent + Child

34. SWAN Coupling
Interactions to ocean and atm models. This will happen in you #define SWAN_MODEL and one more of: #define ROMS_MODEL #define WRF_MODEL

35. To activate these processes in SWAN
Need to activate
CURRENT
WLEV
FRIC
to get data from ROMS
Need to activate
WIND
to get data from WRF
No READINP since this data
is coming from other
models

36. WAV interactions ATM WAV OCN 1) Generation – wind speed forcing
Uwind, Vwind
WAV
1) Generation – wind speed forcing
is modified by ocean currents:
S(w) = f( Uwind – us ; Vwind – vs )
us, vs, h, bath, Z0
OCN
2) Propagation
– wave celerity in geographic space is modified by ocean currents
cx = cgx + us ; cy = cgy + vs
– change of wave direction (refraction) due to h, bathy, and currents:

37. OCN interactions t t OCN WAVE Hwave, Lmwave, Lpwave, Dwave,
Tpsurf, Tmbott, Qb,
Dissbot, Disssurf, Disswcap,
Ubot
OCN
WAVE
#define CRAIG_BANNER
#define CHARNOK or
#define ZOS_HSIG
#define TKE_WAVEDISS
#define COARE_OOST
#define COARE_TAYLOR_YELLAND
#define DRENNAN
CRAIG_BANNER (default)
#define WEC_VF
#define SSW_BBL
Water column
Surface stress
Bottom stress t
Stokes + VF
Surface tke flux
s= f ( Zos )
Zoa t
b = f ( Zob )
Hwave, Lmwave, Dwave,
Tpsurf, Qb,
Dissbot, Disssurf,
Disswcap,
Hwave, Lpwave, Dwave, Tpsurf,
Hwave, Lpwave, Dwave, Tpsurf,
Hwave, Lmwave, Dwave,
Tmbott, Ubot

38. = f ( Hwave, Lpwave, Tpsurf )
ATM interactions
ATM
Hwave, Lpwave, Tpsurf,
SST
OCN
WAV
OCN
SST
Momentum
Heat
Surface fluxes
Moisture
= f ( Hwave, Lpwave, Tpsurf )
WAV

39. SURFACE ROUGHNESS CLOSURE MODELS Currently only in MYJSFC and MYNN
CHARNOCK (default)
TAYLOR & YELLAND 2001: TY2001 (#define COARE_TAYLOR_YELLAND)
- Wave steepness based parameterization.
- Based on three datasets representing sea-state conditions ranging from strongly forced to shoaling.
DRENNAN 2003: DGQH (#define DRENNAN)
Wave age based formula to characterize the ocean roughness.
They combined data from many field experiments representing a variety of condition and grouped the data as a function of the wind friction velocity.
OOST 2002: OOST (#define COARE_OOST)
- Wave age dependent formula but it also considers the effect of the wave steepness.

40. Applications Nor Ida (Nov 2009) (waves)

41. Nor’Ida Nov 2009 H Wave heights (m) Bodie Island, NC
wind speed
23 m/s (50 mph) H
Wave heights (m)
Bodie Island, NC
13thNov L L
11thNov
10thNov
Wallops Island, VA
Before
9th Nov
Location 4: Oblique aerial photography from Bodie Island (South Nags Head), NC on May 6, 2008 (top) and December 4, 2009 (bottom), roughly two weeks after the storm. The yellow arrows point to the same location in each photograph. Working from left to right (south to north) in the post-storm photograph, note (1) the dune erosion around the base of the southernmost house; (2) the road perpendicular to the beach has been undermined and has retreated to the approximate location of the orange truck in the 2008 photo; (3) the driveway that has been undermined and has lost pavement ; (4) a large pile of overwashed sand one block back from the beach that was likely cleared from the road; (5) the deterioration of the sand bag structure protecting oceanfront houses; (6) the change in exposed length of pilings on the house on the left (south) and the collapsed house on the right indicating undermining by erosion; (7) the significant erosional scarp located behind two oceanfront houses
Location 1: Oblique aerial photography from Wallops Island, VA on May 21, 2009 (top) and December 4, 2009 (bottom), roughly two weeks after the storm. The yellow arrows point to the same location in each photograph. The protective beach fronting this section of the NASA facility on Wallops Island was severely eroded, exposing what appears to be more than one generation of shore protection structures. Some overwash deposition is evident in the post-storm photograph, particularly in the right (north) half of the image.
8th Nov
Before
wind speed
40 m/s (90 mph)
After
After

42. COAWST (Coupled Ocean – Atmosphere – Wave – Sediment Transport) Modeling System
Hsig, Lwave, , Twave,
Uwind, Vwind, Patm, RH, Tair,
cloud, rain, SWrad, LWrad, LHeat, SHeat
Latitude
SST
MCT
MCT
WRF wind speed
Uwind, Vwind
Longitude
WAVE
SWAN Hsig
OCEAN
ROMS SST
Hsig, Lwave, Dwave,
Tsurf, Tbott,Qb, Wdissip, Ub
This is to say that we analyzed the effect of the interaction indicated with the red and green arrows together.
MCT
us, vs, h, bath

43. SST
WRF + ROMS + SWAN
WRF + ROMS
WRF
GOES

44. Reduced wind speed with waves coupling.
WRF
WRF + ROMS
WRF + ROMS + SWAN
m/s
Reduced wind speed with waves coupling.
Biggest effect was with the waves. Swan used OOST.
DATA
WRF
WRF+ROMS
WRF+ROMS+SWAN S
0.85
0.78
0.89

45. Reduced waves with waves coupling.
WRF + ROMS + SWAN
WRF + ROMS
WRF
WRF
WRF + SST
WRF + SST +OOST m
Reduced waves with waves coupling.
DATA
WRF
WRF+ROMS
WRF+ROMS+SWAN S
0.80
0.74
0.88

46. Reduced wind speed with waves coupling.
WRF + ROMS + SWAN( )
(OOST)
WRF + SST + TY2001
WRF +SST + OOST
m/s
(TY)
WRF + SST + DGQH
(DGQH)
SST + WRF
DATA
WRF
WRF+ROMS
W+R+S (DGQH)
W+R+S (TY2001)
W+R+S (OOST)
NAM
WRF + ROMS
Reduced wind speed with waves coupling.
OOST best.

47. Reduced wave heights with waves coupling.
(TY)
WRF + ROMS + SWAN( )
(OOST)
(DGQH)
WRF + SST + TY2001
WRF + SST + DGQH
WRF + SST +OOST m
DATA
WRF
WRF+ROMS
W+R+S (DGQH)
W+R+S (TY2001)
W+R+S (OOST)
NAM
WRF + ROMS
Reduced wave heights with waves coupling.
OOST best.

48. Increased current speed with waves coupling.
SURFACE CURRENTS
(TY)
WRF + ROMS + SWAN( )
(OOST)
(DGQH)
WRF + SST + OOST
WRF + SST + TY2001
WRF + SST + DGQH
Increased current speed with waves coupling.
TY / DGQH best.
CODAR
WRF + ROMS (charnock)
m/s
m/s

49. Increased current speed with waves coupling.
SURFACE CURRENTS
(TY)
WRF + ROMS + SWAN( )
(OOST)
(DGQH)
WRF + SST + DGQH
Model currents (m/s)
RMSE (m/s) 0.26
RMSE (m/s) 0.13
RMSE (m/s) 0.14
CODAR currents (m/s)
CODAR currents (m/s)
CODAR currents (m/s)
Increased current speed with waves coupling.
TY / DGQH best.
CODAR
WRF + ROMS (charnock)
m/s
RMSE (m/s) 0.24

50. Increased surge with waves coupling.
STORM SURGE
(TY)
WRF + ROMS + SWAN( )
(OOST)
(DGQH)
WRF+ SST + OOST m
WRF
WRF + ROMS
DATA
WRF
WRF+ROMS
W+R+S (DGQH)
W+R+S (TY2001)
W+R+S (OOST)
Increased surge with waves coupling.
TY / DGQH best?