Land-Water Options and Values Outside Grid

To avoid making interpolation across land-water boundaries, i.e. interpolation that includes both water and land point values, you have to tell the tool how to distinguish water from land in your input data file:

·         If your data does not have any land-water boundaries you should choose the first option,

·         If you are interpolating a bathymetry you choose the second option, and

·         If the data has the bathymetry written as a prefix item (e.g. simulation results) you should choose the last option.

The 'zland: Minimum value for true land' value is the value that separates land from water. The value is only relevant if land-water interpolation option is the second or third alternative. All grid points in the new grid which are placed within the land area of the old grid will be given the "zland" value.

If the new grid is not fully enclosed in the old grid, you can specify a value which will be uniformly set at all the exterior points of the old grid, in the new grid. This can either be the delete value, or a user specified value. Finally its also possible to specify values of exterior points relative to the old grid, in the new grid through a .dfs2-file. The file should in that case represent a grid hav­ing the same dimensions as the new grid which you specified earlier, but the file can contain any values for the exterior points of the old grid which you need to specify.