RTTOV v12 Code Updates and Known Issues

RTTOV v12 Code Updates

Updates and bug fixes to RTTOV v12 will be published here.

Known bugs and issues

Please report any bugs you find in RTTOV using the NWP SAF Helpdesk. The official release package for the latest version doesn’t contain the bug fixes or updates listed here under the latest version so you should apply any fixes provided below. Bugs in earlier versions have been fixed in the latest version.

Show/Hide the table of known bugs and other updates in RTTOV v12.2.

DateType/StatusDescription
30/05/2018Bug - fixedAffects: non-solar IR cloud/aerosol simulations. Most likely to affect code where the coefficients structure variable (type rttov_coefs) is allocated dynamically at run-time.

Issue: some potentially uninitialised values in the cloud/aerosol optical properties structure cause intermittent/occasional segmentation faults when they are used to size arrays later on inside RTTOV.

Fix: download this file to src/coef_io/ and recompile RTTOV. Note that this will not work with RTTOV v12.1: see the table below for the v12.1 fix.
25/05/2018Compilation issueAffects: compilation/running of Python wrapper and/or GUI

Issue: some users have found that Python calls to RTTOV or the GUI fail to run. Errors are similar to:
"At line 591 of file ../../src/main/rttov_getoptions.F90
Internal Error: get_unit(): Bad internal unit KIND"

This affects users who use conda and results from an incompatibility with the compiler environment that conda makes available at run-time vs the system default. This problem does not seem to affect miniconda.

Fix: You should try installing the conda gcc package:
$ conda install gcc
And then do a fresh build of RTTOV. You may also have to recompile the HDF5 library with the version of gfortran from the conda gcc package, and then link the RTTOV build to this library. When running RTTOV you may then need to add the library from your conda environment and the updated HDF5 library to the LD_LIBRARY_PATH.

If you are running on Mac OSX then one user discovered that the following worked:
$ conda install clang_osx-64 clangxx_osx-64 gfortran_osx-64
10/05/2018Optional updateAffects: output warnings when apply_reg_limits is true.

Description: in v12.1 and earlier, no warnings are printed out when input profiles exceed the regression limits if the apply_reg_limits option is true. In v12.2 warnings are printed out regardless of apply_reg_limits. This update reverts to previous the behaviour.

Update: download this file to src/main/ and recompile RTTOV.
09/05/2018Updated test reference dataAffects: RTTOV-SCATT

Description: since the RTTOV v12.2 release, updated Mietable files were made available for download (see the coefficients download page). These result in changes to the test outputs for the test_rttovscatt.sh and run_example_rttovscatt_fwd.sh scripts which now differ to the test reference data included in the v12.2 package.

Update: download and extract this file in the rttov_test/ directory. This will enable you to verify RTTOV-SCATT in your RTTOV installation using the latest Mietable files.
09/05/2018Optional updateAffects: HTFRTC simulations (RTTOV v12.2 only)

Description: in the v12.2 release, HTFRTC cannot be run via the RTTOV parallel interface. This update enables the capability for multi-threaded HTFRTC simulations using OpenMP.

Update: download and extract this file in your top level RTTOV v12.2 directory (e.g. ~/rttov12/) and recompile RTTOV. When compiling you must specify one of the *-openmp compiler flag files in build/arch/ to enable multi-threaded simulations. The update tarball includes the modified example code and associated calling script (src/test/example_htfrtc_fwd.F90 and rttov_test/run_example_htfrtc_fwd.sh) which demonstrates use of the RTTOV parallel interface. NB This update includes the HTFRTC bug fix below. See the separate link below for updated test reference data related to the bug fix.
09/05/2018Bug - fixedAffects: HTFRTC simulations (RTTOV v12.2 only)

Description: due to a bug in the calculation of geopotential height (used in the calculation of local path angles through the atmosphere) there are small errors in the HTFRTC outputs equivalent to up ~1mK in reconstructed brightness temperatures. In addition the rttov_read_coefs_htfrtc.F90 subroutine has been updated to improve compiler compatibility (this has no impact on outputs).

Fix: download and extract this file in the RTTOV v12.2 src/ directory and recompile RTTOV. The fix changes forward model outputs slightly (equivalent to up to ~1mK in reconstructed brightness temperatures), and also has a small impact on Jacobians. Updated reference data for the test_htfrtc.sh script can be extracted in rttov_test/. Output from the example_htfrtc_fwd.F90 example program does not change as a result of this update. NB This bug fix is included in the optional HTFRTC update above.

Show/Hide the table of known bugs in RTTOV v12.1 which have been fixed in RTTOV v12.2. Bugs listed above may also affect v12.1.