The manuscript presents the coupling of an extended version of the model LAVESI, which addressed Siberian larch forests but now can also include further species, with a permafrost model, CryoGrid. The developers of both models are in the authors team. The question addressed is how forest structure and permafrost soil features might change under climate change. The authors show that the coupling with the CryoGrid improves the realism of LAVESI.

The topic addressed is important, the manuscript well prepared and written, and the design of the models, their parameterization, and application look sound. I was a reviewer of the original version of LAVESI and was happy to see its improvements.

Both models are complex and getting them parameterized and then linked was a major effort. Describing this effort takes a lot of space and has been done in all detail.

Nevertheless, it might be worthwhile to start the Methods section with a short characterization of both models, for LaVESI including the original one and the revised one. One way to do so could be filling in a Table for both models with the information required by the Overview part of the ODD protocol for describing models. This would allow readers who are less interest in technical details, at least upon first reading, to get a complete overview of the scales, entities, state variables, and processes included in both models. A detailed description of the scheduling of the combined models process would also be helpful, to better see via which variables both models interact, and how the different temporal resolutions was dealt with. (If all this is described in the Supplement, please refer to the Supplement more explicitly, and more specifically).

The only thing I stumble over while reading with the 20 cm resolution of the "environmental grid" - where does this resolution come from= From the original DEM?

There are some general comments on the the quality of the model predictions in terms or realism (i.e., validation, corroboration). I think this should made more explicit, and more specifically linked to the results. While there might be no single data set allowing for a comprehensive validation, putting different aspects together might help convincing readers that this not only a technical exercise, but indeed improved the predictive capacity of LaVESI. Perhaps, in the sense of pattern-oriented modelling, another Table might make sense which list which aspects of the model output match observations - even if only in the widest, or qualitative way.

Overall, I think this is a great contribution to the modelling of Siberian forests under climate change and, hence, to improving predictions relevant for assessing the global carbon cycle.

Dear Editor/Authors

This manuscript describes a coupled model version amalgamating a one-dimensional permafrost-multilayer forest land-surface model (CryoGrid) with an individual-based and spatially explicit forest model (LAVESI). The authors' approach is extremely important for understanding the current environment of permafrost region and predicting the future, because changes in the permafrost environment due to climate change are closely related to changes in vegetation.

This study certainly has merit, though I’ve got some concerns list below. The main issue in my mind is structure of the methods section. It is unclear for me what new processes have been added or what parameterizations have been conducted in this study. It would be better if the authors organize them clearly and explicitly. For example,  "gdbasalconst", "gdbasalfac" and "gdbasalfacq" , estimated from tree-ring data, are  parameters newly estimated in this study, so (I think) it should be included in Table 1, not Table B1.

If the authors could consider above and below specific comments, I believe that it would improve the readability of this manuscript.

Specific Comments:

P1L27 Should it be Eastern Siberia instead of Central Siberia?

P2L2 Should it be Eastern Siberia instead of Central Siberia?

P2L4-L5 I think the reader will understand better if the authors provide specific examples of the positive feedback.

P4L15 Which parameter in Table 1 could tell us the better low temperature tolerance of the tree species LACA?

P4L25 I think an explanation of gnls-function would help the reader understand it better.

P4L28-L29 "gdbasalconst", "gdbasalfac" and "gdbasalfacq" are now listd in Table B1, not in Table 1. But, I think they should be listed in Table1 because they are newly estimated in this study.

P8L12-L14 Since the authors did not compare the simulation results with observed data (they are only comparing the simulation results from LAVESI and the coupled model), I don't think the term "overestimation" is appropriate.

P8L15 I don't really understand what the authors are trying to say. I think all we can know from Figure 3-4 is that the simulation results from LAVESI and the coupled model are different.

P8L26-L27 What are the factors that cause LAI values to decrease? Could the authors describe possible factors?

P9L11-L12 Reference are required.

P22 I don't see Sato et al., 2010 (in table 1) in the list of references; is that a mistake for Sato et al., 2016?