CCPP-SCM Version 5.0.0

Release Date:

The CCPP-SCM Version 5.0.0 was released on March 8, 2021.

Release Notes

The Developmental Testbed Center is pleased to announce the Common Community Physics Package (CCPP) v5.0.0 public release on March 08, 2021. This release contains the CCPP-Physics, a library of physical parameterizations, the CCPP-Framework, an infrastructure  that connects the physics to host models, and the CCPP Single Column Model, a simple host model that employs the CCPP-Physics and CCPP-Framework. 

The CCPP-Physics is envisioned to contain parameterizations used in the NOAA Unified Forecast System (UFS) for weather through seasonal prediction timescales, as well as developmental schemes under consideration for upcoming operational implementations.  This release contains updated versions of all parameterizations used in NOAA’s operational Global Forecast System (GFS) v15.2 (implemented in 2019), a new scheme (the Noah Multi-Parameterization land surface scheme), plus updated versions of  developmental schemes. New capabilities include additional debugging tools and the ability to output physical tendencies from individual parameterizations and developer-customized arrays.

There are some important changes in the CCPP-Framework in this release. To increase performance while enabling flexibility, the build system has been consolidated around the multi-suite static option and the dynamic build capability has been removed.

Changes in the SCM include the ability to use CCPP v5.0.0, configuration of tracers externally via a file, updated surface initialization code, updated case generation script to better handle LSM-related variables when using initial conditions from the Unified Forecast System, and bug fixes. In addition, there was a change in file names and in the authoritative code repository name (now ccpp-scm) to reflect the close tie between the SCM and the CCPP.

As in the last release, five experimental cases are available for use with the CCPP SCM: BOMEX maritime shallow convection, LASSO continental shallow convection, ASTEX stratocumulus-to-cumulus transition, ARM SGP Summer 1997 continental deep convection, and TWP-ICE maritime deep convection.

The CCPP parameterizations are aggregated in suites by the host models. The DTC provides support for using CCPP v5.0.0 with the CCPP SCM (suites GFS_v15p2, GFS_v16beta, csawmg, and GSD_v1) and with the Unified Forecast System (UFS) Short Range v1 Application (suites GFS_v15p2, RRFS_v1alpha). Suite RRFS_v1alpha is new in this release and is intended for use in convective-allowing configurations. The CCPP v5.0.0 is not intended for use with the UFS Medium-Range Weather Application v1. For access to the SCM and CCPP code and documentation, please visit the CCPP website at, where you will find a Users’ Guide, a list of known issues, frequently-asked questions, technical documentation, and scientific documentation. For information about the UFS, including its use with CCPP, please visit

For questions or comments about the CCPP and the SCM, please use our Forum at When using CCPP with the UFS, you can also direct your questions to the UFS community forum.

Ligia Bernardet and Mike Ek, on behalf of the DTC CCPP team (Dom Heinzeller, Grant Firl, Laurie Carson, Man Zhang, Julie Schramm, and Xia Sun)


Known Issues and Fixes

  1. Using the RRFS_v1alpha suite with the supplied forcing for cases where deep convection is expected to be active will likely produce strange/unreliable results. This is because forcing for existing cases assumes a horizontal scale for which deep convection is subgrid-scale and is expected to be parameterized. The RRFS_v1alpha suite is intended for use with convective-allowing resolutions and as such does not include a convective parameterization. Nevertheless, the RRFS_v1alpha suite is included with the SCM as-is for research purposes.
  2. Users should always review and adjust the case configuration to verify whether it supports the scientific experiments they are conducting. The default configuration may not be optimal for everybody's research.
  3. CCPP Physics physics/GFS_rrtmg_pre.F90. A density calculation uses pressure in the wrong units and is passed into the effective radius calculation for the Thompson microphysics. Affects the Thompson microphysics and suites RRFS_v1alpha and GSD_v1. Preliminary testing shows impacts on the SW radiative fluxes and subsequently temperature. For more information, see the Issue and PR
  4. CCPP Physics physics/module_mp_thompson.F90. Bugs in the formulations of freezing of water drops into graupel/cloud ice, rain collecting snow, and number of aerosols have been identified and are under review. See PR.  Affects the Thompson microphysics and suites RRFS_v1alpha and GSD_v1.
  5. CCPP Physics Scientific Documentation. Namelist variables bl_mynn_edmf_tkeadvect, bl_mynn_edmf_tkeadvect, bl_mynn_edmf_cloudpdf, and bl_mynn_edmf_cloudmix are incorrectly listed and should be bl_mynn_tkeadvect, bl_mynn_tkeadvect, bl_mynn_cloudpdf, and bl_mynn_cloudmix, respectively.
  6. scm/src/GFS_typedefs.F. A bug related to setting the bl_mynn_tkebudget control variable in GFS_typedefs.F90. In particular, the bl_mynn_tkebudget variable is not read in via namelist nor set. This should only affect diagnostic output of the MYNN PBL scheme.  See the issue for a fix.
  7. On some platforms, when executing multiple runs of the SCM using the script, individual runs may fail 'silently', i.e. the script will report that all runs completed successfully when they did not. As a result, do not rely on the script to report success/failure of all runs. Use the script with the '-v' (verbose) option to see console output from all individual runs or the '-vv' (extra verbose) option to write the console output to file to check later. One may also inspect the the output directories for '' files that have the expected size.