Rapid Water Quality Mapping from Imaging Spectroscopy with a Superpixel Approach to Bio-Optical Inversion

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Dear authors,

I found the method you described interesting and innovative. I have, however, some suggestion that if addressed, I think, could improve your manuscript.

1. You did not provide any information on sensor calibration.

2. You did not actually compute reflectance as you do not divide your signal by the downwelling signal. This is important since if there is any change in illumination you will could take it into account and it will appear as a water feature.

3. Since your algorithms are supposed to work on reflectance (Sr^-1) and not Lw/pi, it is not clear how you could apply them.

4. You do not seem to remove surface effects (glint, breaking waves etc'), assuming that all the radiance you measure comes from below the surface. This needs to be stated as it is often the case that surface effects affect measured radiance significantly (I know this is not the topic of this paper).

5. Please provide more information on SLIC as it is critical to understand your method. Is it required that all superpixel be of the same size?

6. Fig. 2 shows cases where there is significant bias in the SLIC result (e.g. large scale underestimation as in 2c 600-1000, large scale overestimation - most of 2f). 

7. It would be good if the axis of Figure 2 was also in pixels as this is what you refer to in the caption.

8. There are no 'Vertical profiles' in Fig. 2. These are horizontal or transect lines. Vertical profile in oceanography refer to trace of measurements over different depth...

9. Fig. 5 - information may be better conveyed via histograms of distributions of value, maybe in addition to your plots (e.g. within them on the right hand lower corner)

10. There are no CDOM particles in the ocean (l. 376). CDOM denotes color dissolve organic material. It is true that both absorption by dissolved and non-algal particulate materials are inverted as one term (often denoted as a_dg).

11. Line 403: m^2.

Dear authors: I am often wrong. If any of my comments is off mark feel free to reach out to me and I will be more than happy to change them if convinced of being wrong.

 

 

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

Detailed reviewer report is attached.

Comments for author File: Comments.pdf

Author Response

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Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

This study provides a valuable solution to the slow speed caused by the huge amount of data in current cartography. This provides convenience for rapid and timely water quality monitoring, so that managers can quickly grasp the information of water changes and formulate effective response plans in a timely manner. Overall, I think this article is acceptable with minor modifications. The following are some specific opinions.

Line 17-18: In fact, in the abstract, chlorophyll-a, suspended particulate matter and colored dissolved organic matter do not need to attach their abbreviations to the full name, because they do not appear for the second time in the abstract, and the abbreviation defined here is not necessary.

Line 26-27: Keywords should be revised. The current keywords seem to be less able to convey the theme and main content of the article. Some words are not even closely related to the theme.

Line 94-96: In fact, “chlorophyll-a, suspended particulate matter, colored dissolved organic matter” has appeared in line 52, and the abbreviation should be explained at the first time, not at the second time. And I suggest to change Chla to Chla, a does not need subscript.

Table 1: Latitude and longitude should have directions ( W, E, N, S ). In addition, the presentation form of this table is not beautiful, some content format is on the left while some is on the right.

Figure 1: There are many kinds of chlorophyll, such as Chl a, Chl b, Chl c and Chl d. The Chl written in Figure 1 and Figure 4, while the text is Chl a, please confirm. Figure 1 is actually very good, but the black background seems to affect its beauty.

Figure 3,4,5: Linear regression results should give a specific p value. If the results do not reach a significant level, even a higher R² is not convincing.

Line 307, 440: Delete inappropriate spaces in sentences.

Line 326: What are acceptable levels of accuracy loss ? Is there a reference standard ? Or pre-defined values ?

Line 370: Change “CDOM R² values” to “the R² values of CDOM”.

Line 382-401: In this part, the author compares and discusses some of the studies of many scholars, but the description of these studies is too long, and it is more important to summarize these researches, rather than to describe too many specific studies.

Line 403 : It should be 20000 m2, 2 should be superscript.

Line 466-470: In the conclusion, the author mentions the practical application of this research and the prospect for the future. But in fact, this part should not be mentioned in the conclusion, but should be mentioned and expanded in the discussion.

Some reference formats are not uniform, please check.

Author Response

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Author Response File: Author Response.docx