Effects of Directional Wave Spectra on the Modeling of Ocean Radar Backscatter at Various Azimuth Angles by a Modified Two-Scale Method
, Tianran Song 1 and Jie Zhang 1,2,3
Round 1
Reviewer 1 Report (Previous Reviewer 2)
This is my second review. I see the manuscript has been revised significantly. Still, the entire manuscript requires a deep revision and some of the sentences are difficult to follow. There are many typos through the article (only some of them are mentioned in the below comments). A careful proof reading required.
1. Line 13 in Abstract: The word “additionally” is redundant.
2. Lines 16-17: Should “know” be “found”? I don’t understand the sentence. Are those spectra are common to the reader?
3. Line 55 on Page 2: Is “the integral equation method scattering model” a standard expression?
4. Line 62 on Page 2: The word “simply” is redundant.
5. Line 65 on the same page: I don’t think the word “undetermined” is appropriate. This word occurs many times in the manuscript. As shown in the later part of the present paper and reference 18, the parameter is not easy to be determined, but it can be determined with various means. Also, should “need” be “needs” when the subject “parameter” is singular?
6. Line 97 on Page 3: Should “find” be “found”?
7. Line 104: What does “separation of spatial” mean?
8. Lines 131-132: Should be “others” be “another”?
9. Eq.(3) on page 4: I don’t see the independent variable K on the right hand side.
10. Line 149: Should be “the phase speed of the wave”, instead of “the speed of wave phase”?
11. Line 152: What is the unit of the minimum phase speed?
12. Line 156: It is difficult to follow the statement.
13. Line 199 on page 6: ‘… with the results in.” is an incomplete sentence.
14. Line 395 on page 12: What does “different dependence” mean? Also, the word “different” in line 400 is redundant.
15. Figure 10 on page 15: Incorrect legend for both ASCAT and CMOD5.n data.
Author Response
Please see the attachment.
Author Response File: 
Author Response.docx
Reviewer 2 Report (New Reviewer)
This is my second review. I see the manuscript has been revised significantly. Still, the entire manuscript requires a deep revision and some of the sentences are difficult to follow. There are many typos through the article (only some of them are mentioned in the below comments). A careful proof reading required.
1. Line 13 in Abstract: The word “additionally” is redundant.
2. Lines 16-17: Should “know” be “found”? I don’t understand the sentence. Are those spectra are common to the reader?
3. Line 55 on Page 2: Is “the integral equation method scattering model” a standard expression?
4. Line 62 on Page 2: The word “simply” is redundant.
5. Line 65 on the same page: I don’t think the word “undetermined” is appropriate. This word occurs many times in the manuscript. As shown in the later part of the present paper and reference 18, the parameter is not easy to be determined, but it can be determined with various means. Also, should “need” be “needs” when the subject “parameter” is singular?
6. Line 97 on Page 3: Should “find” be “found”?
7. Line 104: What does “separation of spatial” mean?
8. Lines 131-132: Should be “others” be “another”?
9. Eq.(3) on page 4: I don’t see the independent variable K on the right hand side.
10. Line 149: Should be “the phase speed of the wave”, instead of “the speed of wave phase”?
11. Line 152: What is the unit of the minimum phase speed?
12. Line 156: I can not follow the statement.
13. Line 199 on page 6: ‘… with the results in.” is an incomplete sentence.
14. Line 395 on page 12: What does “different dependence” mean? Also, the word “different” in line 400 is redundant.
15. Figure 10 on page 15: Incorrect legend for both ASCAT and CMOD5.n data.
Author Response
Please see the attachment.
Author Response File: Author Response.docx
Reviewer 3 Report (New Reviewer)
General comment: The work of this paper is to explore the influence of ocean backscatter on the detection of marine radar at different azimuth angles. At the same time, the simulation results of the TSM model are compared with the results of the CMOD5 model and the ASCAT wind data, and the results are obtained. However, through previous studies, it has been shown that the CMOD5n model algorithm adaptability is high in the global marine environment, and the advantages of the new TSM algorithm are not well reflected in the paper, and the results and discussion seem to deliberately avoid these problems. In addition, the discussion part of the article is not analyzed in depth enough. In general, the relevant research of the article needs to be further developed, and the following are relevant revisions:
PS: I am not sure whether this manuscript have been round-review. I saw red highlight in the text.
Comment 1: Page 1 line 40-41,“TSM is reliable precision and high efficiency”This sentence is too subjective, please add the corresponding reference.
Comment 2: The article describes the comparative validation of ASCAT data in the abstract section, but provides information about this data later in this article (e.g., example figures). None of them appeared.
Comment 3: The overall logical structure of the article is chaotic, and the comparison result chart needs to be modified.
Comment 4: Fig. 7 Page 11, The data in Figure 7 looks particularly chaotic compared with the line. Please modify the line color, including the shape, to make the overall picture more intuitive.
Comment 5: Several papers on the directional wave spectrum and ocean radar backscatter at various azimuth angles have been studied in depth this year. Please indicate the innovation and academic value of this paper in the paper ?
Comment 6: The scope of the corresponding study area has not been explained in the paper, different algorithms may have different inversion results in different sea areas and different ocean states. Please explain this question.
Comment 7: The wind speed and radar incidence angle constraints are analyzed in Figure 10, but the maximum range of wind speed is only 16m/s. For some extreme ocean conditions, the wind speed is often greater than 25m/s. At this time, the applicability analysis of TMS model needs to be reflected in the paper
Comment 8: As for the reference of the article, most of the documents are too old, and many of algorithms have also proved unsuitable for today's ocean research. Please read the latest references carefully to learn more accurate algorithms and make more constructive modifications to the article.
Comment 9: Page 2 line 53-54,“Chen et al. [14] and Xie et al. [15] systematically explored the...”can be modified to “Chen [14] and Xie [15] systematically explored the...”
Comment 10: Page 2 line 55, there is an extra space in the sentence.
Moreover, the backscattering is anticipated for SAR rainfall referred as:
Shao W, Jiang X, Sun Z, Hu Y. Marino A, Zhang Y. Evaluation of wave retrieval for Chinese Gaofen-3 synthetic aperture radar[J]. Geo-spatial Information Science, 2022, 25(2): 229-243.
Guo C, Ai W, Zhang X, et al. Correction of Sea Surface Wind Speed Based on SAR Rainfall Grade Classification Using Convolutional Neural Network[J]. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2022, 16: 321-328.
Author Response
Please see the attachment.
Author Response File: Author Response.docx
Reviewer 4 Report (Previous Reviewer 3)
I am happy with the response of the author to my earlier
review comments, and have no more questions to add.
However, I do have one suggestion for improvement.
I see that a fairly large amount of text has been added
to describe in words the performance of the different models
compared to CMOD5n and ASCAT measurements for a number of
different wind speeds and directions and incidence angles.
Although very comprehensive, this is rather difficult to
digest for a reader.
I think it would be good to try to visualise this in some
type of performance table.
Looking at figures 7 and 8, the variation with incidence angle for the different
cases is mostly an offset, and if the slope is different it can be clearly
seen in the standard deviation of model minus measurement.
Looking at figure 9 the same could be done for wind direction.
Looking at figure 10, the wind speed dependency is much more scattered.
So you could create a table with on one axis wind speed
(3 up to 16 m/s)
and on the other axis the different models+wave spectra
D + Cosine, D + Sech, D + Gaussian, A + Cosine, A + Sech, A + Gaussian,
E + Cosine, E + Sech, E + Gaussian, H18 + Cosine, H18 + Sech, H18 + Gaussian,
AH18 and AEH18
and then indcate in each cell what the offset and standard deviation is of
the curves given in figures 7 and 8.
In that table you could use some color coding to indicate what you
think are good and lesser results.
This way a reader could see in one figure which model performs
best for which wind speed regime.
Author Response
Please see the attachment.
Author Response File: Author Response.docx
Reviewer 5 Report (New Reviewer)
Please find it attached.
Comments for author File: 
Comments.pdf
Author Response
Please see the attachment.
Author Response File: Author Response.docx
Round 2
Reviewer 3 Report (New Reviewer)
I recommend the publication of this manuscript.
Author Response
Thanks very much for the time and effort spent on the manuscript. And thanks for your confirmation.
Reviewer 5 Report (New Reviewer)
Thanks for improving the manuscript.
I think, it would be good to add the equation for converting buoy wind speed to 10 m neutral wind speeds.
Author Response
Thanks very much for pointing this out. The corresponding revision has been made, please see lines 120-123 on page 3.
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
1. The usage of English language and writing style must be improved. In some parts of the manuscript, there is a clear lack of readability.
2. Line 34: Please added more references after ‘e.g., [1]’.
3. Line 75 Please replace ‘modified two-scale model’ with ‘modified TSM’
4. Line 136 please replace ‘gotten’ with ‘obtained’.
5. Line 144: How did you know the A- and E- spectra are the most suitable spectra? How did you evaluate these different sea spectra? please added more explanations.
6. Line 406: Please replace A with another letter, as the parameter A and ‘A spectrum’ are easily confused.
7. Please add the formulas of the three spreading functions (Cosine, Sech, and Gaussian) used in the work.
Reviewer 2 Report
In this paper, the authors investigate the predictions of the azimuthal variation of radar backscattering from the ocean surface with the modified two-scale method. They showed that the selection of both wave number spectra and directional spreading functions has certain effects on the estimation of azimuthal modulation. Although there are some interesting results, the paper is poorly written and suffers from unclear and incomplete scientific reasoning. Some parts from this paper cannot be understood. Therefore, the manuscript requires a major revision before it can be recommended for publication. A few comments are listed below.
1. Lines 12-18 in Abstract: This sentence is long and difficult to follow. Please rewrite it.
2. Line 22 in Abstract: Incomplete sentence. What does “The better …” stand for?
3. Line 35 on page 1: The word “merely” does not make sense here.
4. Lines 53-58 on page 2: This topic sentence is too long. Please rewrite it.
5. Line 131, Eq. (6): The equation has too many constants without any physical explanation. I would suggest the authors consolidate the equation.
6. Line 144 on page 4: Could the authors explain how they evaluate those spectra to be picked? It seems to me that it is arbitrary.
7. Figure 3: Could the authors explain why one peak occurs in each curve for the E spectrum in Fig. 3b and for both spectra in Fig. 3c?
8. Lines 262-264 on page 7: I do not agree. I believe that the performance analysis would result in different conclusions if the modified TSM predictions are compared with the ASCAT data. One evidence is that all plots in Fig. 5 will be completely different if the analysis is based on the data.
9. Lines 281-318 on page 8: These two paragraphs are poorly written. All three figures are discussed once and I have no idea each sentence (paragraph) corresponds to which figure. Please present results figure by figure.
10. Line 411 on page 12: It is strange that “the values of A estimated with A spectrum …”. Do these two As refer to the same thing? If not, please pick a different letter to depict the parameter A in the paper.
11. Line 426 on page 13: What does the word “archives” mean here? The same word appears in Line 437.
Reviewer 3 Report
Comments for author File: Comments.pdf
