Numerical Modelling and Prediction of Oil Slick Dispersion and Horizontal Movement at Bornholm Basin in Baltic Sea

Round 1

Reviewer 1 Report

This is an interesting approach to oil spill modelling that clearly warrants publication Water. I really have only two substantive comments, along with a handful of more minor ones. The first substantive comment is some consideration of how the oil film thickness used or predicted by the model can be validated by field measurements in the discussion section. In particular, predictions that cannot be validated in a field setting may be of limited value. At present, measurement in the field of film thicknesses greater than about a millimeter remain highly problematic. The several issues attending this problem should be acknowledged and discussed in the discussion section. The second  is that I think the discussion section should include a clear account of how and why the modelling approach presented is better than or at least complementary to those already in widespread use, such as SIMAP and GNOME. The explicit modelling of oil thickness is an obvious improvement, but are there any other advantages?

My more minor comments include the following:

1. In the line immediately following equation 12, reference is made to points "P₁" and "P₂", but the object of this sentence is to explain the components of equations 11 and 12, in which the points "P₁" and "P₂" do not appear. Reference to these point is this sentence should be deleted, and if necessary their appearance in Fig. 3 could be pointed out in a separate sentence.

2. In equation 15, what does the arrow indicate? And what is "R2"?

3. In the first paragraph of sec. 3.2, reference to Fig. 6 precedes reference to Fig. 5. The numbering of these two figures need to be reversed to preserve the continuity of the figure's numbering sequence.

4. In equations 34 through 41, what does the "c" preceding sigma or rho  in the second terms of these expressions?

5. In the first line of the penultimate paragraph of sec. 4, what does "B^{(degree sign)}3 mean?

6. In the third sentence of the second paragraph of sec. 5.4, an initial film thickness of 1 cm after 1 h is assumed without justification, which should be provided here. Having witnessed many oil spills, including some of the biggest on record, I have yet to see a film thickess of more than a millimeter or two after an hour's spreading.

The English is almost entirely used correctly in this article, although there are instances where the usage is either somewhat awkward or difficult to follow. A quick edit by a native English speaker will find improving these straightforward. Stylistically though, the repeated use of "The Author" should instead be replaced by the pronoun "I"'

Author Response

I am grateful for the valuable and insightful comments on the paper submitted. The required point by point response has been provided in the attached file. The changes are also visible in the revised manuscript. The Reviewer's comments and suggestions helped significantly to improve the paper.

Author Response File: Author Response.pdf

Reviewer 2 Report

Dear authors

The current study aims to improve an existing oil spill model (Semi-Markov model) in the Bornholm Basin, Baltic Sea. Unfortunately, in my opinion, the entire document content is confused and poorly arranged. I recommend that the author explicitly separate this paper from the sections under methods, results, and comments. There are some other suggestions for enhace manuscript quality:

·       Abstract: I suggest the authors rearrange this section to be more concise and direct to the point you want to convey. For example, what is the main gap that the author will fill in this study? One or two sentences are enough for the introduction part. Be more focused on the results and discussion section and the implications of this current study.

·       Introduction: The author's main reason for using this Semi-Markov model compared to several models that have been developed previously (MIKE, OSCAR, etc.) needs to be clarified. Why do the authors only focus on varying oil layer thickness rather than other variables such as kind of oil, degradation speed, etc.? The main gap of this current study should be clearly mentioned also.

·       Waves and winds at the Baltic Sea: The information in this section is too general. I suggest focusing on the data used in the simulation and the findings of this study. It should be clearly mentioned why the area in this study only focuses on the Baltic Sea (especially Bornholm Basin), compared to other areas.

·       Result: This model tries to present a stochastic-based model. Unfortunately, the result is doubtful since there is no validation to prove that this model has a good agreement with the field (observation) data.

·       Discussion: This section also needs to be more straightforward. Be focused on discussing the main finding in this study and support it with appropriate citations based on previous studies. I also found that the result and discussion in this study is not fully support the decision maker to create a proper mitigation for oil spill.

·       Conclusion: focus on the main goal of this study and its implications.

Best regards

Author Response

Author is grateful for the valuable and insightful comments on the paper submitted. The required point by point response has been provided in the attachment. The changes are also highlighted in the revised manuscript. The Reviewer's comments and suggestions helped significantly to improve the paper.

Author Response File: Author Response.pdf

Reviewer 3 Report

This paper presents an innovative approach to predicting the movement and dispersion of oil spills on water surfaces, with an emphasis on the influence of oil spill thickness and changing hydrometeorological conditions. The author emphasizes the need to develop strategies to reduce water pollution and mitigate the effects of pollution, especially in the maritime sector. The proposed numerical model considers probabilistic approaches and takes into account the change in the thickness of the oil slick layer over time (system analysis theory is applied). By developing a semi-Markov model and using proprietary software, the author was able to predict the movement of an oil slick in the Bornholm basin of the Baltic Sea within two days. Although the study's findings are preliminary, they provide valuable information for those responding to environmental damage caused by oil spills. The model has the potential to be further developed to make more accurate predictions and could be a useful tool for understanding the extent of the problem and minimizing the environmental impact. However, the article contains a number of fundamental comments, which I will discuss below.

Fundamental notes:

1. In your work you use the classical approach of system analysis. He is widely known. You apply it to a new object, but do not add anything to the model itself. You need to correct the article by indicating a specific scientific innovation.

2. Information about obtaining primary data must be added to the article. Where did she come from? Has it been checked for convergence, how relevant is it... etc. The author’s formulation “The obtained research results are preliminary results of predicting the movement and spread of an oil slick, since the input parameters in section 5.3 are assumed arbitrarily” leads the author’s research to a dead end.

3. Links in the article are placed incorrectly. Links in the format “incidents [1,2,3,4,5]”, “presented in [4,6,7,8,9,10,11]” and further are unacceptable.

Notes:

1. Page 4. Text “Natural dispersion can be caused.....” construct a phrase, otherwise it is ambiguous.

2. Not all variables are disclosed in the formulas.

3. Formula 8 error in the index.

4. Figure 3. What is C?

5. Page 13. Invalid number of links “Researches [39,40,41,42,43,44,45]”

6. Page 17. What does the text in figure 16 “from (48)” mean?

Conclusion. The work is positive, but needs serious improvements. The scientific significance of this work is unclear. And the author’s contribution to the development of methods is also unclear. The use of known methods to calculate new results does not constitute a scientific contribution. I agree with 30% of the Plagiarism in the work; the work is based on old generally accepted methods.

Author Response

Author is grateful for the valuable and insightful comments on the paper submitted. The required point by point response has been provided in the attachment. The changes are also highlighted in the revised manuscript. The Reviewer's comments and suggestions helped significantly to improve the paper.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Dear author

After reading the revised manuscript carefully, I found the author already addressed all question properly. I glad to inform you the manuscript is ready for publication. 

Best regards

Reviewer 3 Report

no remarks