The namelist parameters listed in Table 6 are for grid and mask information. During execution, the ice model reads grid and land mask information from the files grid_file and kmt_file that should be located in the executable directory. There are commands in the scripts that copy these files from the input data directory, rename them from global_$ICE_GRID.grid and global_$ICE_GRID.kmt to the default filenames shown in Table 6.
| Varible | Type | Default Value | Description |
| grid_type | Character | 'displaced_pole' | Determines grid type. |
| 'displaced_pole' | |||
| 'tripole' | |||
| 'rectangular' | |||
| grid_format | Character | binary | Grid file format (binary or netCDF) |
| grid_file | Character | 'data.domain.grid' | Input filename containing grid information. |
| kmt_file | Character | 'data.domain.kmt' | Input filename containing land mask information. |
| kcatbound | Integer | 0 | How category boundaries are set (0 or 1) |
For coupled runs, supported grids include the 'displaced_pole' grids (gx3v7 and gx1v6) and the 'tripole' grids.