Example 3. Extract soil temperature data from ERA monthly mean data

#! /usr/bin/env convsh

#  Convsh script getst.tcl
#
#  Extract soil temperature fields from ERA monthly mean, surface GRIB files,
#  where the ERA data is stored in directory /work/n02/n02/jwc/data on Archer,
#  and write out as a netCDF file.

#  Write out netCDF file
set outformat netcdf

#  Automatically work out input file type
set filetype 0

#  Convert soil temperature fields only to netCDF
#  (use Xconv on one file to get soil temperature field numbers)
set fieldlist "1 6 7 9"

#  Era data is contained in /work/n02/n02/jwc/data directory
set dir /work/n02/n02/jwc/data

#  Read in each of the ERA monthly mean, surface files and
#  write soil temperature fields to the output file

foreach infile [glob $dir/era-20c_surface_N80_*.grib] {

#  Replace input file extension with .nc and append st_ to input
#  file name to get output filename
   set outfile "st_[file tail [file rootname $infile].nc]"

#  Read input file
   readfile $filetype $infile

#  Write out soil temperature fields to a netCDF file
   writefile $outformat $outfile $fieldlist

#  Remove input file information from Convsh's memory
   clearall
}