make_sso

routine to compute subfgrid scale orography parameters
from a spherical harmonics method

Requirements:
- SPHEREPACK library
- FFTW ?
- ifortran
- netcdf
- an adequate environment defined in make_sso.env

Options:

 ./make_sso  -i <file>  -v <var>  -res <nlon> <nlat>  -m <mask>  -f <ffac>  -t
  <tfac>
 
 Where:
 
  <file>:   input file name
  <var> :   height variable name
  <nlon>:   number of distinct longitude points of output grid (iim)
  <nlat>:   number of distinct latitude  points of output grid (jjm+1)
  <mask>:   can be:  1. a mask file (o2a.nc)
                     2. "noro": computed with grid_noro
            default: 3. "spec": computed internally
  <ffac>:   filtering  width: ffac*Do         (Do:output resol.)
  <tfac>:   transition width: Di+tfac*(Do-Di) (Di: input resol.)
 
 Note that latitudes grid contains both poles.


Example to compile then run make_sso from a high-resolution Relief.nc file to
a 180x90 horizontal grid. 

./compile
file=Relief.nc
./make_sso -i $file -res 180 91 -v z

Output file is make_sso_180x91_${file}

