Modeling of Extreme Hydrological Events in the Baksan River Basin, the Central Caucasus, Russia
Round 1
Reviewer 1 Report
This is a very interesting study on modelling extreme hydrological events in the Caucasus. Overall, I found this manuscript well written, with consistent results and discussions. The authors used different algorithms for the hydrodynamic modelling, but probably for the readers would have been interesting to see a comparison (or at least a discussion) with other similar algorithms. It is not very clear why STREAM_2D is better than other models. A discussion on this issue might be useful.
I also suggest improving Fig. 1. For most of the readers, the location of Baksan River is unknown, therefore I suggest to add a small inset map highlighting the location of the study area within the region. I also recommend inserting the highest peaks and main contour lines.
In the description of the study area please write a small paragraph about geology and relief. Please mention the elevation of the lake and the lowest elevation of the glaciers.
Move Lines 126-131 to Discussions.
Are there any pieces of evidence of permafrost or glacier ice occurrence within Bashkara dam? It is not clear if permafrost thawing/ice melting played a role in the GLOF extreme event described it. Please clarify!
Overall, I consider this is an honest study in the field of hydrodynamic modelling and I recommend publication after addressing the aforementioned minor issues.
Author Response
Dear Reviewer,
We are very grateful for the overall positive comments, confirming that our work is of interest, which was a great motivation for us to improve the paper further. We have agreed with most of the comments. Following recommendations and constructive feedback, we carefully revised the manuscript and some of the figures. All changes made are highlighted in yellow in the revised version so as to facilitate the revision process.
Please see the attachment.
Best regards, The co-authors
Author Response File: 
Author Response.docx
Reviewer 2 Report
The authors of this manuscript provide the detailed modelling work of high mountainous river-lake system. The combination of hydrodynamic model and runoff formation model aims to describe the precious modelling results of extreme flood events. The logical flow of this manuscript is straightforward. Beside the strength, there are some comments which might be considered by the authors. 1. The manuscript is too wordy, and its description is more like technique report rather than a scientific research work. Please revise the expression by an expert who is familiar with SCI composing. 2. The coupling of hydrodynamic model and runoff formation model is not clear to the readers. How to couple these 2 models? 3. The quality of plots produced by Excel could be rearranged and make the more beautiful. The Figure 10 has not significant information to the readers. It can be described by few sentences. 4. The description of climate change scenarios is not clear. Please make it more specified. 5. More detailed comments could be found in the pdf attachment.
Comments for author File: 
Comments.pdf
Author Response
Dear Reviewer,
We are very grateful for the overall positive comments, confirming that our work is of interest, which was a great motivation for us to improve the paper further. We have agreed with most of the comments. Following recommendations and constructive feedback, we carefully revised the manuscript and some of the figures. All changes made are highlighted in yellow in the revised version so as to facilitate the revision process.
Please see the attachment.
Best regards, The co-authors
Author Response File: Author Response.docx
Reviewer 3 Report
This study modeled the extreme hydrological events in the Baksan River basin using the STREAM_2D hydrodynamic model and the ECOMAG runoff formation model. The research results are within the scope of the Hydrology journal, I suggest that this manuscript can be accepted for publication in the Hydrology journal after major revision.
Comments:
- In the Abstract section, the full name of “STREAM_2D” and “ECOMAG” should be presented.
- What is the spatial resolution for the DEM data?
- What is the spatial resolution for the STREAM_2D hydrodynamic model?
- In Section 3, only simulated river discharges had been compared with observed ones, however, the variations of water level are the most important to flood. I recommend the water level hydrograph comparisons between modeled and measured have to be conducted in the presented study.
- A similar study related to extreme hydrological events in high mountains should be considered in the Introduction section, e.g.,
- Ruiz-Villanueva, V.; Díez-Herrero, A.; Stoel, M.; Bollschweiler, M.; Bodoque, J.M.; Ballesteros, J.A. Dendrogeomorphic analysis of flash floods in a small ungauged mountain catchment (Central Spain). Geomorphology 2010, 118, 383–392.
- Borga, M.; Gaume, E.; Creutin, J.D.; Marchi, L. Surveying flash flood response: Gauging the ungauged extremes. Hydrol. Process. 2008, 22, 3883–3885.
- Yung-Ming Chen, Che-Hsin Liu, Hung-Ju Shih, Chih-Hsin Chang, Wei-Bo Chen, Yi-Chiang Yu, Wen-Ray Su, and Lee-Yaw Lin. An Operational Forecasting System for Flash Floods in Mountainous Areas in Taiwan. Water 2019, 11, 2100.
Author Response
Dear Reviewer,
We are very grateful for the overall positive comments, confirming that our work is of interest, which was a great motivation for us to improve the paper further. We have agreed with most of the comments. Following recommendations and constructive feedback, we carefully revised the manuscript and some of the figures. All changes made are highlighted in yellow in the revised version so as to facilitate the revision process.
Please see the attachment.
Best regards, The co-authors
Author Response File: Author Response.docx
Round 2
Reviewer 3 Report
The authors have well addressed all my comments, I suggest that this paper can be accepted for publication in Water journal.
