3DVAR/4DVAR Observation Converters

Overview

The programs in the obs_converters/var directory help convert data which is formatted for input into the 3DVAR/4DVAR programs into DART obs_seq observation files.

The directory contains conversion programs for various obs formats related to 3D-Var, WRF-Var, and MM5:

• PROGRAM littler_tf_dart to and back from little-r format, temperature and winds only.

• PROGRAM rad_3dvar_to_dart the radar 3d-var obs only to dart format.

• gts_to_dart.f90 from GTS to dart format.

You need to add some WRF-Var source files to the 3DVAR_OBSPROC directory, and then you can go into the work directory and run the ‘quickbuild.sh’ script. The required WRF-Var source files are listed in 3DVAR_OBSPROC/README.

The little-r converter may need changes to the code to convert from the original quality control flags into QC flags compatible with DART. (in DART, 0 is good data.)

The GTS converter does not support SATEM thickness data but there are versions around which do; write dart@ucar.edu if you are interested in more about this.

And a final disclaimer: Whether these work with the latest 3D-Var format is untested at this point. Please contact the DART Development group if you are interested in using these tools.