CESM Models

Known Problems in CESM1.2.1

Dear CESM User,

Beginning in March 2014, all the CESM supported releases known problems (except CESM1.0.5 and prior releases) will be reported and updated using the DiscussCESM Forums

CESM General -> Known Issues -> [sub forum topic]

Please be sure you are subscribed to the CESM General -> Known Issues sub-forum topic(s) of interest by logging into the forums and select options

My Account -> Subscriptions -> Categories

Check all sub-forum topics that you would like to keep informed about and the frequency of notifications.

These particular sub-forums are only accessible for posting by forum moderators and are intended to be used as an avenue for CESM developers to communicate known problems and fixes to the general CESM user community.

CESM users should continue to post their issues either as a topic in the main Bug Reporting forum and/or as a topic in the individual component models' Software and Run-time issues forums.

In addition to the organization of the sub-forums, some hints for searching the new sub-forum known issues topics include searching on phrases such as:

  • "Affected Releases CESM1.0.z" - to find all bug topics associated with the CESM1.0.z (z > 5) release series
  • "Affected Releases CESM1.1.z" - to find all bug topics associated with the CESM1.1.z release series
  • "Affected Releases CESM1.2.z" - to find all bug topics associated with the CESM1.2.z release series

Thank you.
CESM Software Engineering Group

The CESM1.2.1 is the first incremental bug fix and machines update release in the CESM1.2 series.

** IMPORTANT NOTE ** Starting with CESM1.2.1, the Subversion repository path has changed. All documentation for downloading the most current version of the model has been updated in the CESM User's Guide to reflect this change and older version differences are noted.

To download the CESM1.2.1 release code, use this command:

> svn co --username guestuser --password [password] 
https://svn-ccsm-models.cgd.ucar.edu/cesm1/release_tags/cesm1_2_1 cesm1_2_1

You may be prompted up to 3 times for the username and password when checking out the code for the first time from this new Subversion path. This is because the code is distributed across a number of different Subversion repositories and each repository requires authentication.

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Component Sets (COMPSETS)

(Bugzilla 1880) The B_1850_BGC_BDRD, B_1850_BGC_BPRP, B_1850-2000_BGC-BDRD and B_1850-2000_BGC-BPRP compsets must be run from cold start conditions in CESM 1.2.0. If you need to start from a spun-up initial condition, please use CESM 1.0.5.


(Bugzilla 1727) CLUBB can now be run with OMP_NUM_THREADS > 1, but clubb_history is not working with thread > 1.


Known Issue - namelist description of "do_circulation_diags" in CAM's namelist_definition.xml should include:
(Bugzilla 1768) WACCM nuclear winter compset (BNUKE_C4WBC_L40CN) starts from wrong reference case
(Bugzilla 1766) The SE version of gravity_waves_sources in CESM 1.2 has a bug and workaround.
(Bugzilla 1744) WACCM-SE sometimes fails due to race condition with threading (particularly w/ Intel DEBUG)
(Bugzilla 1612) There is a known problem with the following WACCM compsets when the ESMF time manager is used.


(Bugzilla 1733) Driver needs a different list hardcoded in for hist_a2x3hr_flds (important when trying to save data to run CLM later, i.e. CLM spinup).
(Bugzilla 1339) Problem running with "too many files" for datm for over 83 years.


(Bugzilla 1867) irrigated soybean not treated same as rainfed soybean
(Bugzilla 1838) The population density is set to 1850 for 2000_control namelist use-cases.
(Bugzilla 1815) For both CLM4.0 and CLM4.5, crop GDD is incorrect for the first ~20 years.
(Bugzilla 1805) There is a bug in clm4.5 fire model connected to fpftdyn/=' '
(Bugzilla 1776) Issue with CLM45CNDV trees over Amazon.
(Bugzilla 1759) For CLM4.0, the RCP 8.5 file pftdyn for f09 was NOT correctly updated.
(Bugzilla 1634) clm4_0_60 interpinic fails to properly map from 1.9x2.5 to the 360x720 grid for CRUNCEP.
(Bugzilla 1753) Problem with an initial file used in CROP simulations.
(Bugzilla 1719) Minor -- false overestimation of fire C emissions for natural vegetation PFTs without transient land-use change.
(Bugzilla 1717) Minor -- lake hydrology bug when sudden intense snowstorm occurs preceeded by warm weather.
Please refer to the Known Bugs for CLM document for a detailed list of known issues specifically addressing custom configurations for CLM.


(Bugzilla 1861) Issue using RESUBMIT option in env_run.xml when setting certain variables in user_nl_pop2


The CICE history files have some incorrect history fields (albpnd, albice, albsno). These should not be used.


(Bugzilla 1611) Restarts can only happen on year boundaries.

Machines / Scripts

(Bugzilla 1910) Intermittent Problem on Yellowstone with MPI_Wtime call.
(Bugzilla 1882) Bug in config_grid for a couple of tri-grid setups
(Bugzilla 1748) CESM on stampede is still in development.
(Bugzilla 1743) Coordination of variables EXEROOT and RUNDIR in env_build.xml and env_run.xml
(Bugzilla 1737) Decomposition problem on Mira using compset BG1850CN at resolution f09_g16.
(Bugzilla 1736) Intrepid: There is an xml compiler problem with threads, that prevents ne30 F compsets from being able to restart correctly.