CESM Models

CESM1.0 Release Notes


The CESM1.0 Release Notes page contains summary information for each release in the CESM1.0 series, where notable new features are highlighted and known problems are documented as they are discovered.

The CESM1.0 was originally released in June 2010. Since that time, a series of updated versions has been released to the community to provide additional features, bug fixes, and updated machine support. All releases are summarized on this page, with the most recent version listed at the top. To date, the following versions have been released:

There are handful of backwards compatability issues and general features that will hold true for all CESM1.0 Release Tags. Users should be aware of these potentially unexpected behaviors of the CESM1.0 system, so please take a look.

Also, it is important to note that all versions of CESM1.0 supersede CCSM4.0. However, users can run all CCSM4 experiments from the CESM1 code base. In addition, the CCSM4.0 code base is frozen and all future model updates will occur from the CESM1.0 code base.

For complete information about CESM1.0, see the CESM Code Release page, where you will find a scientific discussion of the CESM1.0's notable improvements, model output and diagnostics, complete model documentation, and model inputdata information.

Please note that updates on issues, including bugs, associate with this model release, will be posted on the Known Issues (see below) and through the CESM Bulletin Board. It is the users responsibility to continually keep informed of these issues.

Release Summary for cesm1_0_5

CESM1.0.5 offers out of the box support for the new NCAR machine Yellowstone and the new ORNL machine Titan. It is also the code base we recommend you use for running simulations that are scientifically supported as part of the CESM1.0 - CESM1.0.5 series scientific validation and accompanying diagnostics.

Release Summary for cesm1_0_4

The main purpose of the CESM1.0.4 release is to provide the community a version of CESM1 that supports the Thermosphere/Ionosphere extension of WACCM (WACCMX) and the the capability to configure cases using interannual forcing component sets (CIAF, DIAF, and GIAF). CESM1.0.4 also includes a "patch" to MPI_RSEND that improves cray-gemini interconnect performance on Cray XT6 machines, and it contains other enhancements, machine updates, and bug fixes, as noted in this section. Aside from these new features, the CESM1.0.4 release is an incremental release beyond CESM1.0.3.

Release Summary for cesm1_0_3

Release Summary for cesm1_0_2

Release Summary for cesm1_0_1

Release Summary for cesm1_0

CESM1.0 Backwards Compatability Issues and General Features

There are handful of universal CESM1.0 backwards compatability issues and general features that will hold true for all tags in the CESM1.0 Release sequence. Users should be aware of these potentially unexpected behaviors of the CESM1.0 system:

  • CESM1.0 is not completely backwards compatible with CCSM4.0 restart files. As a result, CESM1.0 branch-start cases cannot be initialized with CCSM4 restart datasets, such as those located in the inputdata/ccsm4_init directory. However, CESM hybrid-start cases can be initialized with CCSM4 restart datasets.
  • The ice-sheet component model, Glimmer-CISM, doesn't support ESMF; it fails to compile.
  • Changing the year for climatological runs using prescribed forcing will yield round-off level changes.