A Comparative Study of Statistical Techniques for Prediction of Meteorological and Oceanographic Conditions: An Application in Sea Spray Icing

Round 1

Reviewer 1 Report

I appreciate the Editor to give me a chance to review an interesting and valuable paper. I found some merits in the both methodology and results. In my opinion, this paper has a good potential to be published in the journal. However, I have also some concerns on the different parts of the manuscript. If the author(s) address carefully to the comments, I’ll recommend publication of the manuscript in the journal:

• Add some of the most important quantitative results to the Abstract.
• Add/Replace the name of the study area to the Keywords.
• Lines 96-102 are not necessary and should be deleted.
• In the last paragraph of the Introduction, the authors should clearly mention the weakness point of former works (identification of the gaps) and describe the novelties of the current investigation to justify us the paper deserves to be published in this journal.
• In the first sentence of Introduction, cite this recent useful paper to improve the literature and to show the importance of your work:

Melt Runoff Characteristics and Hydro-Meteorological Assessment of East Rathong Glacier in Sikkim Himalaya, India

• Discuss the main reasons for the variations of the monthly average of icing rate.
• Focus on the advantages/disadvantages of the proposed method with respect to the obtained results.
• It is necessary to explain the sources of error in this study to consider them in next investigations.
• The quality of the language needs to improve by a native English speaker for grammatically style and word use.

Author Response

The authors would like to thank the anonymous reviewer for his/her valuable time and constructive comments. We very much appreciate the comments and their values. We have incorporated them in the current version of the manuscript. Please find below our detailed replies to the comments in the order they have been mentioned.

 

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• Add some of the most important quantitative results to the Abstract.

Response: The monthly Average Absolute Deviation (AAD) from reanalysis values for the MINCOG estimations with Bayesian, SIS, and MCMC inputs were mentioned in the abstract.

• Add/Replace the name of the study area to the Keywords.

Response: The “Barents Sea” was added to the Keywords.

• Lines 96-102 are not necessary and should be deleted.

Response: The paragraph was deleted.

• In the last paragraph of the Introduction, the authors should clearly mention the weakness point of former works (identification of the gaps) and describe the novelties of the current investigation to justify us the paper deserves to be published in this journal.

Response: The last paragraph of the Introduction was rewritten.  In the former works, the MINCOG model was introduced to simulate sea spray icing. However, to predict sea spray icing for the future, the required input parameters should be predicted and then plugged into the model, which is mainly focused on in this study.

• In the first sentence of Introduction, cite this recent useful paper to improve the literature and to show the importance of your work:

Melt Runoff Characteristics and Hydro-Meteorological Assessment of East Rathong Glacier in Sikkim Himalaya, India

Response: Thanks for the suggestion. We used the following recent article in the Introduction. Accordingly, the first paragraph of the Introduction was revised.

Sevastyanov, D. V. (2020). Arctic Tourism in the Barents Sea region: Current Situation and Boundaries of the Possible. Arctic and North, 39, 26-36. doi:10.37482/issn2221-2698.2020.39.26

• Discuss the main reasons for the variations of the monthly average of icing rate.

Response: The variations of the monthly average of the icing rate are analogous to the variations of the input parameters. Generally, the deviation of predictions by the Bayesian framework is less than the other methods that cause less variation in the simulated icing rate. However, input parameters do not have the same contribution in the ice formation. Although, it is suggested that wave height, wind speed, and temperature have higher contributions to the icing rate (Samuelsen, 2017), further statistical analysis in this regard is required. To this aim, the design of experiments (DOE), and Taguchi methods are recommended in the Discussion to evaluate the contribution of input parameters as well as the performance of each algorithm in the icing rate. Consequently, instead of using the predictions of a single algorithm as inputs for the MINCOG model, an optimum combination of algorithms can be applied.

• Focus on the advantages/disadvantages of the proposed method with respect to the obtained results.

Response: The advantages of the algorithms are resistance, robustness, and speed as already mentioned in the Discussion. Despite the capability of the algorithms in the long-term prediction of meteorological and oceanographic conditions, one drawback is that the conditions were separately predicted and the correlations between them were not examined. Considering the influences of the meteorological and oceanographic conditions on each other in the model design might lead to even better results. Thus, as mentioned in the Discussion, further investigation in this regard is suggested for later studies.

• It is necessary to explain the sources of error in this study to consider them in next investigations.

Response: In order to investigate the source of error and improve the algorithms, different aspects of the algorithms should be evaluated through the DOE method. For instance, the SIS and MCMC algorithms were designed using Weibull distribution with two sample sizes of 200 and 500. It is suggested to use other distribution functions such as Normal to fit the data. Then, combinations of different distributions and stopping criteria should be evaluated via DOE or Taguchi method. Consequently, the source of error can be distinguished to enhance the algorithms. This point was suggested in the Discussion for the later studies.

• The quality of the language needs to improve by a native English speaker for grammatically style and word use.

Response: The language was reviewed and slightly modified.  

 

Author Response File: Author Response.pdf

Reviewer 2 Report

The article is certainly in the scope of the journal. The topic is important and the rationale in the introduction is convincing. The level of English is rather fine, so is the structure of the paper, although I would suggest to split discussion from the results. My detailed comments are listed below. Please, note, that I evaluated mostly geoscience aspects, where I am an expert. Here, I have no doubts the science is sound. However, I am not able to evaluate fully the advanced inference statistics methods. I hope the other review(s) could cover these. I have one major concern related to the model design (Lines 91-95). The rest of my comments are moderate or minor.

Detailed comments:

Title: in Spray à In Sea Spray

Line 73: Please, explain the abbreviations upon first use.

Line 75: What do you mean by verification score?

Lines 84-85: What you describe here is rather a study are and not a scope

Lines 87-90: There are discrepancies between this list and the structure of Section 2

Lines 91-95: In my opinion, your model will be stronger if you use 30 years for predictions and 3 years for verification

Lines 96-98: Again, this seems not to reflect the structure of Section 2

Lines 101-102: I am not sure if this sentence is needed

Line 107: ‘Torrents of numerical data’ sounds weird

Lines 129-130: Why ‘therefore’ is used here?

Results and Discussion: I strongly recommend to split it into separate ‘Results’ and ‘Discussion’ sections

Figure 11: Replace commas with dots

Tables 5-10: AAD should be explained in each table so do other abbreviations (for example in table notes)

Lines 518-527: This paragraph sounds rather like a summary and not conclusions and I am not sure if it is needed here.

Line 549: Revise to ‘<1 h and <1.5 h’

References: formatting style is not consistent among the entries

Author Response

The authors would like to thank the anonymous reviewer for his/her valuable time and constructive comments. We very much appreciate the comments and their values. We have incorporated them in the current version of the manuscript. Please find below our detailed replies to the comments in the order they have been mentioned.

 

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• Title: in Spray à In Sea Spray

Response: “Spray” was replaced by “Sea Spray” in the title.

• Line 73: Please, explain the abbreviations upon first use.

Response: Perhaps, ICEMOD is the abbreviated form for ICE MODel, and RIGICE04 is a combination of the two words “RIG” and “ICE”, which is an icing model especially applicable to offshore drilling rigs. However, the abbreviations of these two well-known icing models are not explained in the online literature.

• Line 75: What do you mean by verification score?

Response: We mean the error of the modeled values from the observed values. In the study conducted by Samuelsen et al. (2017) (Samuelsen, E.M.; Edvardsen, K.; Graversen, R.G. Modelled and observed sea-spray icing in Arctic-Norwegian waters. Cold Reg. Sci. Technol 2017; 134, pp. 54-81. doi:10.1016/j.coldregions.2016.11.002) the models were verified using ship-icing data from Arctic-Norwegian waters, outside Alaska, and at the east coast of Canada. Accordingly, the MINCOG model provided lower errors from the observations (i.e., higher verification scores) than the other ship-icing models. Accordingly, the manuscript was revised.

• Lines 84-85: What you describe here is rather a study are and not a scope

Response: “Scope” was replaced by “area” throughout the article.

• Lines 87-90: There are discrepancies between this list and the structure of Section 2

Response: The structure of Section 2 was edited by revising the title of subsection 2.2.

• Lines 91-95: In my opinion, your model will be stronger if you use 30 years for predictions and 3 years for verification

Response: Daily Average Absolute Deviations (AADs) for the two scenarios (i.e., using 30 and 32 years of data for prediction) were compared using the hypothesis test (two-sample t-test). However, the results did not indicate a significant difference between the numbers of years that are chosen for prediction. The tests for wind speed related to MCMC200 and MCMC500 are shown below. Accordingly, since the p-values in both cases are larger than the standard significance level of 0.05, the null hypothesis that the scenarios have similar results cannot be rejected. 

t-Test: Two-Sample – wind speed – MCMC 200	30 years	32 years
Mean	2.65	2.60
Variance	4.49	4.03
Observations	365	365
df	726
t Stat	0.36
p-value	0.72

 

t-Test: Two-Sample – wind speed –  MCMC 500	30 years	32 years
Mean	2.68	2.61
Variance	4.32	3.80
Observations	365	365
df	725
t Stat	0.45
p-value	0.65

 

• Lines 96-98: Again, this seems not to reflect the structure of Section 2

Response: The structure of Section 2 was edited by revising the title of subsection 2.2.

• Lines 101-102: I am not sure if this sentence is needed

Response: As the other reviewer suggested, this paragraph was removed.

• Line 107: ‘Torrents of numerical data’ sounds weird

Response: “Torrents of numerical data” was replaced by “A large amount of numerical data”.

• Lines 129-130: Why ‘therefore’ is used here?

Response: “therefore” was replaced by “accordingly”.

• Results and Discussion: I strongly recommend to split it into separate ‘Results’ and ‘Discussion’ sections

Response: Results and Discussion was split into two separate sections.

• Figure 11: Replace commas with dots

Response: commas were replaced by dots

• Tables 5-10: AAD should be explained in each table so do other abbreviations (for example in table notes)

Response: AAD was explained in the footer of the tables

• Lines 518-527: This paragraph sounds rather like a summary and not conclusions and I am not sure if it is needed here.

Response: The paragraph was revised.

• Line 549: Revise to ‘<1 h and <1.5 h’

Response: “Less than 1 hour and 1.5 hours” was replaced by “<1 h and <1.5 h”

• References: formatting style is not consistent among the entries

Response: The reference format was revised.

 

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

The authors have dealt well with most of my comments and the remaining issues are minor. However, I underline again I am not able to cover some advanced statistics parts of this paper. I encourage the scientific Editor to verify that this expertise is covered by another reviewer.

The aforementioned minor comments are as follows (the lines refer to the original version):

Lines 91-95: If these numbers are true they are convincing but please mention this information somewhere in the discussion sections and include the tables reported in the answer as supplementary material.

Lines 129-130: Accordingly to what? 1) SMS was not yet discussed in this paragraph. Moreover, in other places you talk rather about SIS, so why here you introduce SMC?

Tables 5-10: The other abbreviations such as SIS or MCMC should also be explained in the notes

Lines 518-527: OK but the passage between this and the next paragraph is somewhat strange in this version (I mean the usage of the word ‘Meanwhile’).  

Author Response

The authors would like to thank the anonymous reviewer for his/her valuable time and constructive comments. We very much appreciate the comments and their values. We have incorporated them in the current version of the manuscript. Please find below our detailed replies to the comments in the order they have been mentioned.

 

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• Title: Lines 91-95: If these numbers are true they are convincing but please mention this information somewhere in the discussion sections and include the tables reported in the answer as supplementary material.

Response: The information and one of the tables were mentioned in Discussion.

• Lines 129-130: Accordingly to what? 1) SMS was not yet discussed in this paragraph. Moreover, in other places you talk rather about SIS, so why here you introduce SMC?

Response: The paragraph was revised in which SMC was replaced by SIS.

• Tables 5-10: The other abbreviations such as SIS or MCMC should also be explained in the notes

Response: All of the abbreviations were explained in the notes. However, according to the journal’s instructions, abbreviations in the tables should be defined the first time they appear in the first table. Therefore, the abbreviations are not explained in the second table and thereafter.

• Lines 518-527: OK but the passage between this and the next paragraph is somewhat strange in this version (I mean the usage of the word ‘Meanwhile’).  

Response: The following sentence seems to be unnecessary and confusing to be mentioned here. So, it was eliminated.

“Meanwhile, the assumption that the meteorological and oceanographic conditions are being generated based on a Gaussian process was evaluated through the Ander-son-Darling test.”

Author Response File: Author Response.docx