Black Sea Freezing and Relation to the Winter Conditions in 2006–2021

Round 1

Reviewer 1 Report

This is an interesting and detailed study on the trends of sea ice formation in the Black sea with a special focus on the meteorological drivers accounting for the phenomenon.

It is well presented and organised and I recommend its publication once some modifications are made (see attached revised MS).

In summary, I consider that some Figures should be improved. Specifically, Fig. 5 has too small lettering so labels are very difficult to read. In Fig. 11  it is stated that the trend lines are depicted for two different periods, but in the Fig, this is indistinguishable.

Also,  some parts of the MS should be moved to the Methods section: e.g. description of WSI. Also, in Methods, it should be explained the method used to detect time trends.

See the annotated text for further comments. 

Comments for author File: Comments.pdf

Author Response

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Reviewer 2 Report

The study by Matov investigates the weather conditions favoring Black Sea freezing in the pat 15 years. The analysis of the weather patterns during the periods of maximal sea extent indicates that favorable for freezing in the northern Black Sea is combined influence of Siberian High and Arctic air mass penetration on the periphery of a high latitude Atlantic cyclones. The results are interesting but the analysis has some mistakes. The sea ice has a lag from the weather, so I think the authors shall provide further analysis to support their conclusions.

Author Response

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Reviewer 3 Report

This article has an interesting topic and presents the original results on “Black Sea freezing and relation to the winter conditions in 2006-2021”. The work has the potential to generate interest. The quality of tables and figures in the manuscript is ok. The article is well-written and just needs a minor revision:

1. Introduction can be improved. Clearly mention research gaps and research objectives. What is the need for study? Also, mention the novelty of the study.
2. A table should be included with the information and source of the data used.
3. The innovation points should be highlighted more clearly.
4. Results and discussion: the results are well presented, but the reasons should be given to explain why these results occur.
5. Please also point out the deficiency of the study in the conclusion section. You can mention from aspects of method, data, step, and others.
6. Please improve grammar of the paper.

*. Most of the references are too old. Please update them by using more references published after 2015. You can cite the following paper as example (DOI Mentioned).

• https://doi.org/10.1016/j.jhydrol.2021.127402

Author Response

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Reviewer 4 Report

This paper presented the sea-ice extent variability in the Black Sea and the weather patterns favorable for freezing occurrence in the last 15 years. And the winter conditions change during the latest one century is also discussed by using winter severity index. The results are helpful to further comprehend the winter condition in Black Sea. However, there are some problems to be further improved as well:

1. The innovation of the manuscript is not distinctive. Introduction is suggested to be improved to highlight the original creativity.
2. 5: no WSI lines in Batumi, Istanbul, Sinop and Trabzon. Figures or legends are needed to be modified.
3. Line 175: “freezeng” should be “freezing”
4. In section 3.3, only synoptic conditions for the freezing occurrence are discussed, which are not corresponding to the description of “The aim in our study is to try to evaluate the importance of the seasonal and synoptic conditions for the freezing occurrence in the Black Sea.” (Line 176-177). Further discussions are needed. The intercomparison between the high WSI years and the low WSI years are suggested to be investigated.
5. Section 3.4 and 3.5: Weakness of different data combination to describe the long-term change of ice cover and WSI are suggested to be described.
6. Line 346: What’s the new result or difference between this paper and Matov et al. (2020)?
7. Pay attention to the improvement of references citing.

Author Response

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Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

No comments anymore.

Reviewer 4 Report

My questions are answered. The manuscript is rcecommended to be accepted.