Community Earth System Model 2 (CESM2)

Note: The CESM2.2.z release is not a scientifically supported version; that is, we do not have any long simulations with this model version yet. In most cases, users should continue to use the CESM2.1.z series for their science and especially for CMIP6-related simulations.

Scientific Validation

Scientific validation consists of a multi-decadal model run of the given component set at the target resolution, followed by scientific review of the model output diagnostics.

• CESM2 Experiments, Data & Diagnostic Output *
• CESM2 Naming Conventions

* This page now contains links to datasets on ESGF, CDG, glade and NCAR HPSS as well as diagnostic plots and caseroot details.

Use Cases

Listed below are several common use cases with links into the corresponding on-line documentation.

• Running CESM2 on a supported machine using a scientifically supported out-of-the-box configuration
• Creating, setting up and building a CESM2 case
• CESM2 Component Configuration Settings for component namelist and XML input parameters.
• Postprocessing CESM2 output data on NCAR supported machines using parallel python tools
• Verifying the port of CESM2 to a new machine
• Getting help as a registered user of the DiscussCESM Forums

Prognostic Components

Each model component page contains descriptions and documentation for active or prognostic models.

• Atmosphere
• Land
• Land Ice
• Ocean
• River Runoff
• Sea Ice
• Wave

CIME Documentation

Common Infrastructure for Modeling the Earth contains the coupling infrastructure, support scripts, data models and utility libraries needed to create a single-executable coupled Earth System Model.

• CIME User Guide

* CIME does not contain any prognostics components and is available in a stand-alone package that can be compiled and tested with just its data components.

Configurations and Grids

Component configurations include settings required for CIME enabled models; both prognostic and data model components. These settings include:

• Grid Resolutions
• Component Sets
• Component Configuration Settings

* Includes Fortran namelists and CASEROOT variable definitions

Supported Machines & Performance Data

• Supported Machines and Compilers
• Timing, Performance and Load Balancing Data
• Running on a Medium-Sized Linux Cluster
• Verify a Machine Port

External Library Documentation

• Parallel I/O Library (PIO)
• Model Coupling Toolkit (MCT)
• Earth System Modeling Framework (ESMF)
• External Python Based Tools*

* Support for these tools is currently limited to NCAR machines only

Model Input Data

As of CESM2, the input data necessary to run all supported component sets is made available from a number of different public repositories including:

•  GridFTP
• |
•  Anonymous FTP
• |
•  Subversion