ROMS-SWAN - WET&DRY in SWAN?

[Gabriel_Carvalho]

Dear Rommers,

I'm implementing a nearshore model, with ROMS and SWAN coupled (using COAWST), and Wet and Drying capability.

The problem is:
in roms grid, the negative 'h' values goes for dry cells, and as the sea level rises, the dry cells passes to wet cells (no problem here). But it seems that SWAN simply mask the negative bathymetry values and, when the sea level rises, the dry cells continues not computed in SWAN, although the wet cells goes deeper (the FS elevation is being well passed from ROMS to SWAN).

Do anyone weather or not SWAN has the wet and drying capability and how to implement it?

Thanks a lot,

Gabriel
PROOCEANO - Rio de Janeiro

[jcwarner]

the coupling should pass the water levels to swan, swan will compute new depths, and then determine if a cell is wet or dry. SWAN has always had the ability to read in changing water levels and then detmermine if a cell is wet or dry. so this in itself was not a new feature that i added to swan. If you check your swan bathy.bot to make sure those cells are not permanently dry (ie with a 9999 value ).
-j

[Gabriel_Carvalho]

Thanks Warner,

my file .bot is following the same logic of my roms grid: 'wet' bathymetry values (>0), 'dry' bathymetry values (<0, at the analytical beach), and 'mask' values (9999 values). After I read the last reply, I thought that maybe the problem was with the DEPMIN value (0.05m), that would say to SWAN that all my 'dry' cells (<0) were to be == 0.05.
Then I changed DEPMIN to -1 and SWAN doesn't even compute anything. It seems to me that SWAN doesn't understand negative values in the .bot file.

Do anyone knows how to set 'dry' cells in SWAN, and what DEPMIN should I use?

Thanks a lot,
Gabriel

[jcwarner]

this is not really the correct place for this discussion, but i will provide some more guidance. Suggest you also look at the SWAN manual and look on the swan discussion forum.
Dont confuse bottom elevation to total water depth. SWAN will compute a total water depth on each cell for each time step. Swan will compare the total depth to the Depmin value. For cells that have a total water thickness(depth)) less than Depmin, that cell will be dry in swan. It is similar to Drcit for ROMS. Setting depmin to a negative value does not make sense. there can not be negative total water depths. (again, dont confuse water thickness (depths) to elevation.)

I am not sure if the inlet_test has cells that become dry. that is a coupled application. but we have other applications where the tide comes in/out and tidal flats get dry in both roms and swan, and then get rewet on the next hi tide and become active again.

[Gabriel_Carvalho]

Thanks again warner!
Sorry for using this forum to ask something more specific of SWAN model, but swan forum is not as used as this is (there is not a topic explaning this issue, and no one answer to this question there), and the SWAN manual doesn't comprises this issue either (issue: how to provide "altimetry" values in the .bot file) - And this is a issue that arises with the coupling scope (tides + beaches + waves + sed. trans.) and I thought that maybe this forum would be the place to find people who have already tried to do this simulation.

My problem is simple, I don't know how to provide SWAN with bathymetry values that are above the water level, so that, when the water level rises, this cells would become wet. (The originaly wet cells are becoming dry in SWAN with no problem, in my application).

I have tried to provide negative values in the .bot file, because it's the way used in ROMS grid, but SWAN seems to mask cells that have negative bathymetry values in .bot file.

So, if someone knows how to make it, I will be most gratefull for the help!

Thanks a lot,
Gabriel

P.S: I have searched some application that have this issue and didn't find either.