A Comparative Study of the Temperature Change in a Warm Eddy Using Multisource Data
Round 1
Reviewer 1 Report (Previous Reviewer 3)
Many revisions have been made in the manuscript, but there are still many problems.
1 There are many English abbreviations in the abstract, but the meaning of the English abbreviations is not explained.
2. The 18 lines in the bottom of the summary "The OAT measurements are primarily the path-averaged temperature." are useless and need to be deleted.
3. On line 22, I also think "OAT is feasible as a tool to study mesoscale eddy properties in the deep ocean". But only through the case analysis of this study, I don't think the conclusion "while HYCOM data are not accurate enough in the deep ocean" can be deduced. A more accurate description of the paper should be that the simulation of this eddy is not accurate enough.
4. There are still many problems in writing the Introduction. First, the research value of the South China Sea eddy is not described. Secondly, in line 41, although it is emphasized that the acoustic signal changes in the eddy, no detail is mentioned. At the same time, I think it is unreasonable to cite ten documents in a row in research papers.
5. The second paragraph of the Introduction gave me the feeling that the phenomenon were studied because the phenomenon were observed. In fact, the manuscript Introduction can be written better. Introduction writing can be based on the following ideas. Because of the significance of the eddy research and the specific changes of the acoustic signal in the eddy, an eddy was observed in this study.
6. Tables 1 and 3 are suggested to be combined into one table.
7. The movement of the vortex is depicted by SLA in Figure 3. However, since there is neither anomalous velocity nor drawing of eddy edge in the figure, the eddy is not obvious. It is recommended to add eddy boundaries or surface velocity anomalies to the original image.
8. It is suggested to modify the colorbar in Figure 5. The unreasonable customization of the Colorbar resulted in the inability to observe the strongest temperature anomaly in No. 20210820 of Figure 5.
9. The subfigures of each figure need to add (a) (b)...At the same time, the manuscript needs to refer to Figure 7(a), etc., instead of directly citing Figure 7.
Author Response
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Reviewer 2 Report (Previous Reviewer 1)
All questions were well answered and explained, the revised version has significantly improved, the data and results are worth of being published.
Author Response
Thank you for your suggestions, all of them are very important and they are guiding me in my manuscript and scientific work!
Round 2
Reviewer 1 Report (Previous Reviewer 3)
The manuscript has been revised many times and has been greatly improved, but some problems still exist.
Line 55 of the text ‘Understanding the forward problem…’ is written according to the manuscript and should be treated as another paragraph. The content of the previous paragraph will be the forward problem. The next paragraph introduces ocean acoustic tomography as the inverse problem, and introduces the latest related research. At the same time, the original manuscript lacks sufficient description of the latest research on ocean acoustic tomography. The frontier work on the forward problem occupies a lot of space, but the main focus of this study is the inverse problem, which lacks enough descriptions of previous work.
Author Response
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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
Mesoscale eddy is a normal phenomenon and frequently happening in the northern South China Sea. As of now most of the studies on mesoscale studies were based on the data of satellite and traditional in-situ observation such as mooring, buoy, Argo float and glider etc. Temperature and velocity structure are the key features to be investigated in the studies of mesoscale eddy. This paper presented a new method of acoustic tomography (OAT) which is fairly interesting new way to study mesoscale eddies. To help author to improve the manuscript, I would like to suggest as below:
(1) to focus on how to utilize OAT measurements to capture main features of eddy instead of comparing altimeter satellite data and HYCOM model product data of the eddy passing through the experimental area.
(2) depth level of hydrophones in each mooring should be given in the mooring configuration information so that readers can understand which depth level of which OAT measures the temperature.
(3) to calculate the temperature anomaly data along all the possible sound channels from the sound travel times, and construct a 3D structure of the eddy, which will be very interesting the readers.
Questions:
(1) In paragraph 2.3.4, when you remove the background temperature value to get the anomaly, you use path-averaging method to get mean temperature of each grid point along the sound channel, is Ti,j the grid point data of HYCOM at a certain depth or a vertical averaged grid point data?
Author Response
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Reviewer 2 Report
The text of the article is quite well structured, the illustrations are read quite clearly and allow you to see the conclusions described in the text. (Figure 10 - instead of circles denoting measurement sites, there are semicircles, is this a feature of the experiment or an inaccuracy of the figure?). The conclusions state that for the first time the existence of a mesoscale vortex was confirmed by both satellite altimeter data and model data, however, for this region, there have already been works comparing the data of the same model (HYCOM) and satellite altimetry data (for example, Wang, M., Zhang, Y., Liu, Z. et al. Temporal and spatial evolution of a deep-reaching anticyclonic eddy in the South China Sea. Sci. China Earth Sci. 62, 1002–1023 (2019). https://doi.org/10.1007/s11430-018-9318-6). It seems to me that emphasis should be placed on a new technique for obtaining information about the vortex structure through measurements of the OAT. In general, the work is interesting.
Author Response
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Reviewer 3 Report
The manuscript describes the temperature of the mesoscale eddy in the South China Sea through the ocean acoustic tomography data, and compared it with HYCOM data. However, the manuscript has several problems. First, the original manuscript is more like a technical report and lacks in-depth research. Second, the author seems to want to study the movement and temperature evolution of mesoscale eddy, but the original manuscript does not have this content. Third, the Introduction section lacks a generalization of previous work.
The specific questions are as follows:
1. The description of the cyclone eddies and anti- cyclone eddies in the first paragraph of the manuscript has no relevance to this study and is suggested to be deleted. Here it is necessary to write about the influence of mesoscale eddies.
2. Lines 49 to 53 of the manuscript seem to contain two parallel transitional sentences, but the latter content does not match the transitional content. Firstly, corresponding content needs to be added after each sentence, and secondly, the following content has nothing to do with these two sentences. Modifications are required. This paragraph suggests changing to this model: Firstly, briefly introduce previous work, and introduce the research progress of the three-dimensional structure of mesoscale eddies. Then put the content from lines 49 to 52 of this paragraph at the end of this paragraph.
3. There is a big problem at the end of the second paragraph of the manuscript. Firstly, there are two ‘However’ in the manuscript, which is very repetitive. The last sentence should not be the end of the paragraph, and I don't see the relationship of the last sentence in the paragraph. Therefore, this paragraph needs to be revised as a whole in accordance with the previous suggestion.
4. From line 80 to line 81, "experimental validations of these works have yet to be accomplished due to the difficulty of conducting these kinds of experiments; in other words," should be all deleted.
5. The manuscript is line 82. Since Mikryukov et al. and Liu et al. [30,31] have used acoustic tomography to explore mesoscale eddies, what are the innovations in your manuscript? needs to be reflected in the manuscript.
6. Looking at the Introduction as a whole, there are many problems. First of all, the previous research results and research progress were not written, and secondly, it lacked a description of the benefits of this research. This led to the inability to clarify the purpose of the method establishment in the last paragraph. This paragraph needs to be described as follows: it is necessary to briefly describe what the research needs to do, and then describe how the original text is arranged to achieve this purpose. This is more reasonable.
7. In the second chapter of the original text, Data and Methodology, the method written is too long. If the method of use is used by the predecessors, you only need to quote the references for a brief description. If the method is self-created, a long description like a manuscript is needed.
8. The content of the original manuscript needs to be sorted out. The key point of the paper is behind the Result, but seven of the 15 pictures in the full text are not the key point content. It is recommended to delete the previous pictures if they can be deleted, and to merge them if they can be merged. Figures 1 to 7 only need one or two pictures.
9. It is recommended that all legends need to be written clearly. The legend in the original manuscript was written too simply.
10. There are too many blank spaces in Figure 8, it is recommended to redraw.
11. The manuscript was no discussion. The discussion in the original manuscript should be placed in the Results. Discussions need to describe the strengths and limitations of your own work. Not represented in the original manuscript.
12. Section 4.4.1 appears twice.
Author Response
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Round 2
Reviewer 3 Report
The manuscript has been revised to address some of my previous issues. However, there are still some problems.
1. Figures 1 to 4 are only background introductions and method introductions, accounting for a large proportion of the four figures in the full text. This greatly affects the structure of the manuscript, and it is recommended to delete it appropriately. If some pictures must be retained, it is recommended to combine them. Only one or two pictures are left.
2. In Figure 5, it is recommended to mark the color of 0m high as white, so that the drawing will be more beautiful. At the same time, four circles of information need to be added to the annotation of Figure 5. Although it has been mentioned in the manuscript, the illustration should also be mentioned.
3. The annotation in Figure 6 is not a conventional annotation format. The correct annotation should first tell you what the picture is. Generally, the drawing notes do not describe inference.
4. Figure 7 has the same problem as Figures 5 and 6. Usually, the white area represents the zero point. The original drawing is easy to misunderstand. The information of four circles needs to be described below.
5. The annotation in Figure 9 “The variation in sound velocity with time obtained from the array is very consistent with the correlation coefficients of the time series more than 0.97.” I can't see it in Figure 9.
6. It is needed more description on why mesoscale eddies research is important in 35 to 36 lines of the manuscript. At the same time, I do not see the comparison between the acoustic signals of the cyclonic eddies (CEs) or the anticyclonic eddies (AEs) in this study, so ' Mesoscale eddies are classified as either cyclonic eddies (CEs) or anticyclonic eddies (AEs) based on their direction of rotation. ' is recommended to be deleted.
7. The second paragraph of the manuscript is very confusing. The newly added part does not match the original part very much. It's very confusing to read. It is suggested that this paragraph be reorganized and modified.
8. Chapter 4.1 to 4.4 in the manuscript should be placed in the Result chapter. This part should be placed in the Discussion chapter.
9. The last paragraph of the original manuscript should be the Discussion chapter. The position needs to be converted.
10. The author hopes to study the movement and temperature evolution of eddies (lines 61 to 62 of the manuscript). However, the research focus of the manuscript is to compare the temperature signal with the HYCOM mode data. Therefore, the Introduction section of the manuscript needs to be changed. Or the part about movement and temperature evolution in the manuscript will be studied in depth, which is obviously not the focus of the manuscript.
Author Response
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