                     ROPP_PP Package Release v10.0
                    ------------------------------

The ropp_pp module is a package of software and supporting files for the
processing of profiles of L1 and L2 channel excess phase or bending angles
measured during a radio occultation to compute ionospheric corrected bending
angle and refractivity profiles.  It also contains a tool to calculate
tropopause height from bending angles, refractivities, dry temperatures and/or
background temperatures.

ropp_pp forms one module of the Radio Occultation Processing Package (ROPP)
which is a key deliverable of the ROM SAF. The package relies on utility
routines in the ropp_utils module. The sample test programs interface  with data
files using the ropp_io module. Users wishing to build only those  parts of the
ropp_pp code with no ropp_io dependencies need not install the  ropp_io module.
Please refer to the installation guides of those modules for  further
dependencies.

See the ROPP Release Notes html file provided with the main ROPP download
tarfile for an overview and instructions for installing this module with the
build and configure tools provided with ROPP.

The undulation calculation requires the use of high resolution data files,
copies of  which are available in the distribution at $ROPP_SRC/ropp_pp/data.
The ROPP_PP tools that need these files will look for them, but if they cannot
be found the full pathnames will need to supplied as environment variables
GEOPOT_COEF and GEOPOT_CORR.  For example:

> export GEOPOT_COEF=$ROPP_ROOT/ropp_pp/data/egm96.dat
> export GEOPOT_CORR=$ROPP_ROOT/ropp_pp/data/corrcoef.dat

See the README.unix and README.cygwin files for more detailed installation
instructions and tips for experienced developers. See file MANIFEST for the
complete list of files in the distribution package and the COPYRIGHT file for
copyright information. The file INSTALL contains generic instructions for the
configure script.

Any comments on this software should be given via the ROM SAF
Helpdesk at http://www.romsaf.org


ROPP Development Team
Met Office

Version 10.0
30 September 2020
