Variability of Glacier Velocity and the Influencing Factors in the Muztag-Kongur Mountains, Eastern Pamir Plateau

Round 1

Reviewer 1 Report (New Reviewer)

General comments

There are still some problems with the structure of the paper and its contents. 

(1) The introduction is too long, with some parts dealing with the study area which are then developed in part 2 “Study area and data sets”. So there are still several repetitions.

(2) Also, it does not seem that there is any clear answer to the question raised in the first review “Why the Muztag-Kongur mountain glaciers are selected in this work?”  

(3) In the discussion (lines 381-382) it is written that “the velocity data of glaciers on the western slopes were not used in the linear regression”. If they had been used, would your results (lines 396-397) be the same? This could have possibly increased the correlation.

 

Detailed comments

- lines 42-44: Check the English

- line 65: When mentioning the Karakoram-anomaly, you must quote Hewitt, who was the first author to use this expression “anomaly”. The full reference is: Hewitt K., 2005. The Karakoram Anomaly? Glacier Expansion and the “Elevation Effect,” Karakoram Himalaya. Mountain Research and Development, vol. 25, n°4, Nov. 2005, pp. 332-340.

- line 68: You should go to the line from “The Muztagh-Kongur (…)”

- lines 69 to 75: The English sentences are not clear

- line 84: In general, you only cite the reference number(s). Why the names of the authors here? You have to be consistent

- line 213: Misquotation (see below my remark on reference 39)

- lines 223-225: Check this sentence (not clear)

- lines 227-230: Avoid repeating what is already in your section 2.2. 

- line 233: As mentioned for line 84, you quote the names of two authors. But in this case, it is even more serious because you quote only the first authors, forgetting the co-authors "et al." as mentioned in the reference list

- lines 269-270: Why always repeating yourself? “Figure 3 shows…”; “As shown in Fig. 3…”

- line 301: You refer to section 5.2. which does not exist

- line 332: Cite the numbers of the glaciers as shown in Table 2.

- line 373: You mention “from 2015 to 2016”: if it is for only one year, as expressed by your curves, you should mention only 2015.

- line 375: Similar problem for graphs (c) and (d)

- lines 377 to 385: simplify your text and delete repetitions

- line 385: Delete “The results are shown in Figure 10”, since it is written again line 392.

- lines 409-412: Make the sentence more concise

- lines 416-417: If the effect of topography should be considered, why did you remove the results from the western slopes? (see the general comments)

 

Figure

- Figure 5: Why the units of y axes are different between the external graphs (1990-1999 and 2013-2020) and, the central graphs (2000-2012)?

 

References

- line 491: capital letter to Iran is missing

- line 500: capital letters to High Mountain Asia are missing

- line 507: capital letter to Pamir is missing

- line 556, reference 39: the reference is wrong, with confusion between the first names (as written here) and the full names of the authors, only indicated by their initials. Authors’names are: Ayoub, F.; Leprince, S.; Avouac J.-Ph. 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report (New Reviewer)

In this study, the authors used data from Landsat images and a frequency-domain cross-correlation algorithm to extract the inter-annual glacier velocity. As supplemental data, Inter-Mission Time Series of Land Ice Velocity and Elevation (ITS_LIVE) were used to derive the inter-annual glacier velocity. Temperature and precipitation data were incorporated to analyze glacier velocity changes in the Muztag-Kongur Mountain from 1990 to 2021. A dataset of glacier surface motion along the Karakoram Highway was used to analyze monthly velocity changes of typical glaciers during the year. Finally, the authors elaborated on the influence of glacier scale, slope, aspect, and debris cover on glacier velocity. The design of the study is clearly presented and the methods are adequately described. The presented results and conclusions are supported by the data. This manuscript is therefore worthy of being published.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

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

Temporal and spatial changes in glaciers are the important indicators of the climate and topographic changes. Based on multi-source remote sensing data products from 1990 to 2021, this paper obtains the spatio-temporal changes of Muztag-Kongur Mountain Glaciers. However, many problems occur in the paper, I do not recommend for publication in the current version.

The major comments:

1.The descriptions about the important conclusion in the paper is not conclusive. (1) The changes of the glaciers were described in three time intervals, but the time intervals are corresponding to the used datasets from different sensors. Thus, the important conclusions are likely brought by the original data products, but not related to the real changes of the glaciers. (2) I am confused by the data used in this work. “ITS_LIVE data during the period of 2003-2012 were also employed in this research 137 partly due to sensor problems of Landsat Landsat-7 Enhanced Thematic Mapper Plus 138 (ETM+) sensor after 2003.” But the spatial resolution of the ITS-LIVE data is bad. Also, though the Landsat 7 ETM+ has sensor problems, the Landsat 5 TM still works in this period. Why not use the data? 

2.The presentation of the paper is not good. There are abundant analysis, and the description of the work is lengthy. It is hard to understand what the authors want to express.

 

Minor comments:

1.Why the Muztag-Kongur mountain glaciers are selected in this work?

2.What does it mean in the expression “Temporal and spatial changes in glaciers play an important impact in climate and topographic changes.”? You mean, “climate and topographic changes” are brought by the “Temporal and spatial changes in glaciers”? That is wrong.

3.The description of the terms are not proper in many places, e.g. “…use the Landsat 4, 5 143 image 1-4 band and Landsat 7, 8 panchromatic band”, only the panchromatic band is used from landsat 7 and 8? Moreover, the description of the datasets does not agree with the content in Table 1.

4.Section 2.2 of the paper has several problems. First, the authors don't actually use Sentinel-1A data, but use “the dataset of glacier surface motion along Karakoram Highway (KKH)” produced by others using Sentinel-1A. Therefore, Sentinel-1A should not appear in the statement in the first paragraph of Section 2.2 and Table 1, but “the dataset of glacier surface motion along Karakoram Highway (KKH)” should appear. Second, the authors should add the resolution of ITS_LIVE data used after “The data has resolutions of 120 and 240 m.” in line 149. Finally, the authors don't add a corresponding reference to “the dataset of glacier surface motion along Karakoram Highway (KKH)”, which is not in line with academic principles. Because “the dataset of glacier surface motion along Karakoram Highway (KKH)” is obviously not the product dealt with in this paper.

5.How about the co-registration accuracy in Section 3.1? 

6.Please give the corresponding citation to “COSI-Corr” in the first paragraph of Section 3.

7.Line 205 of page 6: “…from 2013 to 2021 ranged from 0.008 m·d-1 to 0.15 m d-1.” Here, “0.15 m d-1” is inaccurate. From the right figure in Figure 3, it should be around “0.226”.

8.Figure 2 does not give a full description about how to process the data. Here, I am confused that how to get the glacier velocity?

9.Line 205, what does it mean “. From 2000 to 2021.”？

10.How to consider the snow covered on the glaciers in winter?

11.Line 278: the definition of the glacier length is not scientific.

12.Figure 4: (1) "/" should be removed from the title of colorbar. (2) In the legend, “Debirs Cover on Glacier” is not found in Figure 4. (3) The format of longitude and latitude is different from that above, please unify. (4) The unit of the scale bar is marked as "M", why is it not "Km"? (5) Why is "2" marked in the upper right corner of the figure? If it is meaningful, please explain it accordingly.

13.Figure 4: Why go to the median? If the average is selected, will the result of linear fitting change greatly?

14.Line 322 of page 11: Did you use the sentinel-1A product? In the methods in Section 3, there is no processing of sentinel-1A. Therefore, it is recommended to add the relevant data and the reference.

15.Figure 7: Figures 7a and b are somewhat ambiguous, and it is recommended to use a higher DPI plotting method.

16.Figure 8: (1) Figure 8b is not clear. (2) Why is "2" marked in the upper right corner of the figure? (3) The label fonts in the legend of Figure 8a are inconsistent.

17.Line 491 of page 16: syntax error. It should be revised as “Figure 12 and 13 show…”.

18.Line 504 of page 16: syntax error. “As can be seen in Figures 11, 12, and 13. The western branch of…”

19.Line 539 of page 17: The name of Figure 11 is wrong.

20.In Conclusion: In the first paragraph, “sentinel-1A” should be omitted, because you do not directly use sentinel-1A data. It is recommended that you replace the name of the corresponding velocity product (“A dataset of glacier surface motion along Karakoram Highway (KKH)” or not? line 152 of page 4) obtained by sentinel-1A.

21.The three conclusions in Section 6 are not refined enough, and they are not consistent with the four contributions proposed in the last paragraph of Section 1. 

There are still many errors in gramma,  citation, and the expression of the Figures in the paper.