Grid Generation
Grid Generation Software
Several software packages are available to generate the orthogonal curvilinear grids that ROMS requires.
SEAGRID by Chuck Denham
A GUI-based Matlab program for creating curvilinear orthogonal grids with 4 corners SEAGRID includes tools to create ROMS NetCDF grid files. See seagrid for more information.
GRIDGEN by Pavel Sakov
A C program for creating curvilinear orthogonal grids with an arbitrary number of corners.
- http://www.marine.csiro.au/~sakov/ (scroll down Pavel's page to the section on "orthogonal grid generation")
- Rob Hetland has a nice movie about how to make a ROMS grid using GRIDGEN with Python
Bathymetry
The bathymetry for ROMS is measured positive downwards, from a datum such as mean sea level (MSL). For a 'typical' ROMS application, the bathymetry would consist of all positive values. Also, for a 'typical' application, the bathymetry can not have values of 0 or any negative values. Most users would set some minimum 'clipping' depth and not allow the values of h to be less than that depth. However, if an application requires land, i.e. values of h that are negative, then the user is required to activate the WET_DRY CPP option.