One way nesting scripts for serial and MPI SELFE.

The purpose is to generate elev2D.th.nc, SAL_3D.th.nc, TEM_3D.th.nc and/or
 uv3D.th.nc from a large-domain run to be used in a small-domain run. 

(1) use interpolate_variables*.f90 to generate *D.th.nc for the small-domain run.
    Since SCHISM does not allow open bnd nodes to become dry, you may need to be careful
    about the location of the open bnd for the small-domain run.
(2) use the new *D.th.nc for the small-domain run.

interpolate_variables.in is the sample input. 

