Decharme et al. (2026) A process-based modeling of soil organic matter physical properties for land surface models – Part 2: Global land surface simulations and mineral soil compactness adjustment

Identification

• Journal: Geoscientific model development
• Year: 2026
• Date: 2026-08-06
• Authors: Bertrand Decharme, Diane Tzanos, Lucas Hardouin, Aaron Anthony Boone, Marie Minvielle, Patrick Le Moigne, R. Gaillard
• DOI: 10.5194/gmd-19-7239-2026

Research Groups

• MétÃo-France, CNRS, Univ. Toulouse, CNRM, Toulouse, France
• Faculty of Environment, Science and Economy, University of Exeter, Exeter, UK

Short Summary

This study evaluates the impact of a process-based framework for representing soil organic matter (SOM) physical properties on global land surface simulations using the ISBA-CTRIP modeling system. The framework improves the internal consistency of SOM representation in land surface models without requiring additional inputs or calibration.

Objective

• Evaluate the performance of the new physically based SOM parameterization in global land surface simulations.
• Assess the impact of representing mineral soil compactness on these simulations.

Study Configuration

• Spatial Scale: Global, with a spatial resolution of 1°.
• Temporal Scale: Multidecadal (1948–2010) forced by a standard meteorological dataset and driven by SoilGrids soil inputs.

Methodology and Data

• Models used: ISBA-CTRIP land surface modeling system, developed at the Centre National de Recherches MétÃéorologiques (CNRM).
• Data sources: SoilGrids 2.0 database for globally gridded estimates of soil texture, bulk density, and SOC content; Princeton Global Forcing (PGF) dataset for meteorological forcing fields.

Main Results

• The new process-based scheme produces more consistent large-scale hydrothermal responses than the previous empirical scheme.
• The mineral soil compactness adjustment plays a secondary role and mainly acts as a local modulator.

Contributions

• This study provides an improved physically based framework for representing SOM physical properties in land surface models, addressing limitations of existing empirical parameterizations.
• The results highlight the importance of accounting for mineral soil compactness when simulating soil water retention and hydraulic conductivity.

Funding

• Not specified.

Citation

@article{Decharme2026processbased,
  author = {Decharme, Bertrand and Tzanos, Diane and Hardouin, Lucas and Boone, Aaron Anthony and Minvielle, Marie and Moigne, Patrick Le and Gaillard, R.},
  title = {A process-based modeling of soil organic matter physical properties for land surface models – Part 2: Global land surface simulations and mineral soil compactness adjustment},
  journal = {Geoscientific model development},
  year = {2026},
  doi = {10.5194/gmd-19-7239-2026},
  url = {https://doi.org/10.5194/gmd-19-7239-2026}
}