How to handle land boundaries

[lcbernardo]

Hi everyone,

I have a simple question regarding land boundaries/land masking in the ROMS model. I have been modifying some of the ROMS matlab scripts for creating initial and boundary conditions for my study site, and I notice that in the temperature and salinity fields, the value 65535 is inserted in the grid cells masked out as land. I tried to use the input files I created and immediately the run blows up. In the output however, I notice lines such as:

(Tmin= 0.0000 Tmax= 10.0000)
(Min = 3.39651375E+01 Max = 6.55350000E+04)

in the boundary information. Does ROMS automatically recognize 65535 as a cell masked out as land? Or is it better to set such values to maybe zero, or a realistic value?

Best regards,
Lawrence

[kate]

ROMS will check for a _FillValue attributes on fields it reads in. If the matlab scripts set this on the fields it writes you should be OK. Also, if there are wonky values inside the land mask, I would have thought ROMS wouldn't care, since it zeroes them out at run time.

If you make a grid, make the ini/bc files, then edit the land mask, that could be trouble.

[lcbernardo]

Hi Kate,

Thank you for your reply and advice. I'll look more closely into the _FillValue attribute. I'll also try getting rid of the wonky values and see what happens with the model run.

Lawrence