Parameter Constraints for Sensitivity Analysis in CLM5

[krivers]

Hi all,

I'm currently conducting a sensitivity analysis for a few grid cells using CLM5. As part of this, I've modified values in the ctsm60_params.c241119.nc file to assess the influence of specific parameters.

I'm looking for guidance on whether any of these parameters are internally constrained by others within CLM5. For example, in the NOAH-MP model, field capacity is constrained by the soil's maximum saturation—any violation of this relationship prevents the model from running. I'm wondering if similar dependencies exist in CLM5 that I should account for when creating parameter samples.

I’ve reviewed several relevant studies, including:

• Kennedy et al. (2024): One-at-a-time parameter perturbation ensemble of the Community Land Model Version 5.1
• Dagon et al. (2020): Machine learning to assess Earth system model predictability
• Massoud et al. (2019): Ensemble modeling of land surface processes
• Gao et al. (2021): Exploring parameter interactions in CLM

While these are incredible helpful, they don’t go into detail about parameter interdependencies or constraints.

If anyone has experience with parameter interactions in CLM5 or knows of relevant documentation or best practices, I’d really appreciate your insights. Understanding these constraints is key to conducting a robust and physically consistent sensitivity analysis.

Thanks in advance!


What version of the code are you using?
------------------------------------------------------------------------
git describe:
release-cesm2.1.5-0-g7a6c5b0
------------------------------------------------------------------------
release-clm5.0.37

Have you made any changes to files in the source tree?
No changes.