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Supported Development Release2.2.0 Supported Production Release2.1.3

The Community Earth System Model (CESM) is a fully coupled, global climate model that provides state-of-the-art computer simulations of the Earth's past, present, and future climate states. Please post your question to the most appropriate forum topic.

CSEG Announcements

CESM related announcements posted by CSEG
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Non-component-specific topics

CESM General

Questions on CESM in general, or for which you are unsure of the correct forum. Please try to identify a more specific forum if possible.
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CESM Community Projects

Community projects including the Large Ensembles (LENS) and Last Millennium Ensemble (LME).
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CESM Diagnostics and Postprocessing

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Infrastructure (CIME, porting, machines, scripts)

CIME, case control system, build and configure, machines and supporting scripts.
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781
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4.5K

Data Models

The CESM data models perform the basic function of reading external data, modifying that data, and then sending it to the driver via standard CESM coupling interfaces. The driver and other models have no fundamental knowledge of whether another component is fully active or just a data model. In some cases, data models are prognostic and also receive and use some data sent by the driver to the data model. But in most cases, the data models are not running prognostically and have no need to receive any data from the driver.
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73
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189
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Containers & Cloud Platforms

Focusing on CESM issues on the Container (Docker) and Cloud (AWS) platforms. Additional platforms will be added in time.
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Machine Learning

This forum was created after the closing discussion at the Machine Learning session during the 2021 CESM Workshop. You can view the live replay on YouTube: https://www.youtube.com/watch?v=xcwN1ORyCSI

* Note this forum is currently only for discussion, no staff support will be provided

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Specialized Configurations

High resolution/variable resolution

This forum is for technical and scientific questions related to running CESM with high resolution and variable resolution grids. Since many users are currently solving similar problems independently it is our hope that this forum will serve as a community resource where we can exchange ideas and experiences. With user input, we hope to compile a table of working configurations as well as document difficulties and solutions when running CESM with new grid configurations. We expect to cover the construction of grids/meshes, mapping files, and boundary data as well the configuration of component parameterizations and time step modifications specific to new grid resolutions.
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Simpler Models

This forum is for technical and scientific questions related to the simpler model configurations within CESM, such as aquaplanet, dynamical core, SCAM etc

http://www.cesm.ucar.edu/models/simpler-models/
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162
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Paleoclimate

The Paleoclimate Working Group contributes to the our understanding of climate change through hindcast simulations, comparing model results to data given forcings and boundary conditions (i.e. CMIP5 and PMIP3) and through sensitivity simulations to explore uncertainties in forcings. The working group is also involved in the development of modules for CESM for paleoclimate applications. Many paleoclimate modeling questions can be answered in the Paleo documentation. The Paleoclimate forum is intended for questions regarding implementation of forcings and boundary conditions specific to paleoclimate modeling.
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145
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490
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490

Alternative Earths

This forum was created after the closing discussion at the Alternative Earths session during the 2021 CESM Workshop. You can view the live replay on YouTube: https://www.youtube.com/watch?v=v-szhDkf5DYI

* Note this forum is currently only for discussion, no staff support will be provided

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Atmosphere

CAM

The Community Atmosphere Model (CAM) is the atmosphere model component of the CESM. Information about running CAM as the atmospheric component of the CESM is found in the CESM2 release documentation. For information specifically on running CAM6, visit the CAM6 User's Guide. Please see the Whole Atmosphere Community Climate Model (WACCM) Forum and the Chemistry Climate (CAM-Chem) Forum for topic discussions specific to these capabilities of CAM.
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CAM-Chem

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WACCM

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  • fvitt

Land, River Runoff

CTSM, CLM, MOSART, RTM

The Community Terrestrial Systems Model and river runoff models including the Community Land Model (CLM5.0 and CLM4.5), RTM and MOSART of the Community Earth System Model. Descriptions and details are available at https://www.cesm.ucar.edu/models/cesm2/land/ and https://www.cesm.ucar.edu/models/cesm2/river

This forum is also for help with CTSM in other atmosphere models, such as WRF via LILAC

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Ocean

POP

Support of specific science objectives of the CESM and maintaining a state-of-the-art ocean component for the CESM as well as conducting related, but curiosity-driven, research leading to new contributions to the CESM community are the primary goals of the Ocean Model Working Group (OMWG). The former goals ensure that our working group, through CESM, fully contributes to science. The latter is absolutely necessary to keep the CESM at the leading edge of ocean climate models. This, of course, requires a continuous high level of effort and support. Information on the new ocean model component of the CESM can be found at http://www.cesm.ucar.edu/models/cesm1.0/pop2/
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MOM6

This forum is for technical and scientific questions related to MOM6, including but not limited to its use in CESM.
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BGC, MARBL

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WW3 (Wave Model)

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Sea Ice

CESM CICE

CICE5 is the latest version of the Los Alamos Sea Ice Model, sometimes referred to as the Community Ice CodE. It is the result of a community effort to develop a portable, efficient sea ice model that can be run coupled in a global climate model or uncoupled as a stand-alone ice model. It has been released as the sea ice component of the Community Earth System Model (CESM), a fully-coupled global climate model that provides simulations of the earths past, present and future climate states. CICE is supported on high- and low-resolution Greenland Pole and tripole grids, which are identical to those used by the Parallel Ocean Program (POP) ocean model. The high resolution version is best suited for simulating present-day and future climate scenarios while the low resolution option is used for paleoclimate simulations and debugging. Future releases of CICE will be handed through the CICE Consortium.
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CICE Consortium

The CICE Consortium is a group of stakeholders and primary developers of the Los Alamos sea ice model (CICE), formed to maintain the current CICE model for existing and new users, to incorporate and maintain new research and development, and to accelerate scientific sea ice model development and its transfer into operational use. Sea ice modeling and development within the CICE Consortium. Details and documentation available at https://github.com/CICE-Consortium
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Land Ice

CISM

Ice sheet modeling in CESM. Details and documentation are available at http://www.cesm.ucar.edu/models/cesm2/land-ice/.
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21
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Historical / Archive

Forum posts from previous versions of the CESM model.
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