Coupled multilayer canopy-permafrost model (CryoGrid) for the use with an individual-based larch vegetation simulator (LAVESI)

CryoGrid is a land-surface scheme dedicated to modeling of ground temperatures in permafrost environments. Here, the one-dimensional land surface model (CryoGrid) is adapted for application in vegetated areas by coupling a multilayer canopy model (CLM-ml v0). This model setup is used to reproduce the energy transfer and thermal regime at a study site in mixed boreal forest in Eastern Siberia. The vegetation module forms the upper boundary layer of the coupled vegetation-permafrost model and replaces the surface energy balance equation used for common CryoGrid representations. The coupled model was first described in the following article which has been published in Biogeosciences: 

Stuenzi, S. M., Boike, J., Cable, W., Herzschuh, U., Kruse, S., Pestryakova, L. A., Schneider von Deimling, T., Westermann, S., Zakharov, E. S., and Langer, M.: Variability of the surface energy balance in permafrost-underlain boreal forest, Biogeosciences, 18, 343–365, https://doi.org/10.5194/bg-18-343-2021, 2021. The model code for this publication can be found here: https://doi.org/10.5281/zenodo.4317106

In a second publication, the model has been extended by a parameterization for deciduous forest to simulate the leafless state of deciduous-dominated regions outside of the short vegetative period in summer. A more realistic canopy structure is simulated by allowing fractional composition of deciduous and evergreen taxa within the simulated forest stand. Further, we have implemented a new relationship for phase partitioning of water in frozen soil (freeze curve): 

Stuenzi, S. M., Boike, J., Gädeke, A., Herzschuh, U., Kruse, S., Pestryakova, L. A., Westermann, S., and Langer, M. (2021). Sensitivity of ecosystem-protected permafrost under changing boreal forest structures. Environmental Research Letters, 16(8), 084045. https://doi.org/10.1088/1748-9326/AC153D. The model code for this publication can be found here: https://doi.org/10.5281/zenodo.4603668. 

Here, we have added the possibility to couple our model to a dynamic larch vegetation simulator (LAVESI). LAVESI is publicly available on GitHub at https://github.com/StefanKruse/LAVESI the branch used for this study is https://github.com/StefanKruse/LAVESI/tree/CryoGrid_multispecies and the commit used for the simulations for this study is 93a9767. The final commit will be permanently stored on Zenodo.

The parameters are set to the default values that were used for the simulations in the article. Parameters different from the default values can be specified in the main script run_CG_RUN_1D_STANDARD.m (general parameters, run number, etc.) and in the excel table \results\test_vegetation_snow_1\ test_vegetation_snow_1.xlsx (run-specific parameters).

To start the program, run the script run_CG_RUN_1D_STANDARD.m. The default output directory is .\results\.

Further updates to the model code can be found here: https://github.com/CryoGrid/CryoGrid/tree/vegetation

Updates and documentation of the Permafrost model CryoGrid can be found here: https://github.com/CryoGrid. The model is further described in this publication: Westermann, S., Langer, M., Boike, J., Heikenfeld, M., Peter, M., Etzelmüller, B., & Krinner, G. (2016). Simulating the thermal regime and thaw processes of ice-rich permafrost ground with the land-surface model CryoGrid 3. Geosci. Model Dev., 9(2), 523–546. https://doi.org/10.5194/gmd-9-523-2016.

The multilayer canopy model was first published by Bonan et al. (2018): Bonan, G. B., Patton, E. G., Harman, I. N., Oleson, K. W., Finnigan, J. J., Lu, Y., and Burakowski, E. A.: Modeling canopy-induced turbulence in the Earth system: a unified parameterization of turbulent exchange within plant canopies and the roughness sublayer (CLM-ml v0), Geosci. Model Dev., 11, 1467–1496, https://doi.org/10.5194/gmd-11-1467-2018, 2018.