CTSM's custom Python environment

We have written our Python tools to be used with a custom Conda/Mamba environment called ctsm_pylib. This can typically be installed with ./py_env_create. However, ctsm5.3.040 introduced some changes in this environment and the tools, so if you already have a copy of ctsm_pylib your installation instructions will be different.

The new ctsm_pylib conda environment will be incompatible with our tools from before ctsm5.3.040 and vice versa. If you already have a working copy of ctsm_pylib installed, we thus suggest keeping that around under a different name. Here is the suggested command for doing this in a local copy of ctsm5.3.040 or later:

./py_env_create -r ctsm_pylib_old

This will first rename your existing ctsm_pylib to ctsm_pylib_old, then install the Python 3.13.2 version as ctsm_pylib. (If you’re not sure whether you already have ctsm_pylib installed, you can still use that command—it will just stop if you do, and otherwise will install as usual.)

Information about additional py_env_create options—including how to install a fresh copy of the old conda environment—can be found like so:

./py_env_create --help

If you have any questions or run into issues, please post a GitHub Discussion.