Analysis of the Variability and Influencing Factors of Ice Thickness during the Ablation Period in Qinghai Lake Using the GPR Ice Monitoring System

Round 1

Reviewer 1 Report

This manuscript describes GPR measurements paired with meteorological data from a lake in NW China. Whilst the technology is interesting, the results are not too exciting. The description appears a bit lengthy, some of the results appear trivial. Given the effort that went into this study, the data might be worth publishing. But it would be good if the authors can shorten the text a bit and emphasize the key facts and key interpretations. The key chart is in Figure 3. I am not sure if the photographs in Fig.4 are necessary, as they do not really advance the story.

Here some comments by line number:

 

Line 17: need to further specify the location of this lake, province, NW China.

Line 18: why adopted?

Line 19: delete „And then,“

Lines 23+24: change rate

Lines 24-27. This is too much detail. The measurement period is just two and a half weeks in spring. It has to be made clear here, what the focus of this study is. It is not about climate change which requires longer data series. Is it about the method? Proof of concept? Or is it about documenting daily variations? I was a bit lost when reading the abstract regarding the overall objective.

Lines 27-37: These are valid results, although some of them appear a bit trivial. Ice typically melts when temperatures rise. Not really a new result.

Line 43: Do you really mean „hydrothermal“, i.e. hot brines rising from the subsurface?

Lines 48-49: „So far many lake ice studies focused on ice phenology rather than ice thickness.“

Line 58: …with issues related to low…

Line 62: but with deficiencies

Line 65: ice thickness data, and different

Line 67-78: Too many „used“: Try to rephrase to produce a more readable text.

Line 81: Therefore, prolonged

Line 84: if the GPR site is equipped with automatic meteorological station,

Line 88: starts and ends ?

Line 93: Please place modern climate change in to a historical pre-industrial context. Liu et al. 2006 reported palaeotemperature change of Qinghai Lake for the past 3500 years. From their abstract: „Oscillating warm and cold periods could be related to the 20th century warm period, the Little Ice Age, the Medieval Warm Period, the Dark Ages Cold Period, and the Roman Warm Period“. Worth mentioning.

https://discovery.ucl.ac.uk/id/eprint/173622/1/2006GL026151.pdf

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2006GL026151

Line 99: Please specify ablation period: seasonal ablation period during spring. You may also use the word „melting“ instead of ablation.

Line 101-103: rephrase that sentence. Hard to understand.

Line 112: delete „And then“

Line 114: Benefiting from the fast detection speed

Line 121: Add more information on IGPR-30. Who manufactured it?

Line 126: height of 10.35 m over… Question: As the ice thickness changes, this value is unstable, too. You should mention water depth at the location.

Lines 143-152, and rest of text: check english

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

Dear Authors,

The Manuscript can be interesting to readers if any validation information is provided. I have the following comments:

1. Please clarify what is the accuracy of GPR-based ice thickness measurement. Page 6 shows that ice thickness values are represented with accuracy of 0.01 cm. Was such accuracy validated?
2. Was a calibration of GPR system performed?
3. There is no any validation of GPR ice thickness estimates with for example drilling.

Best regards,

Reviewer

Author Response

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Author Response File: Author Response.docx

Reviewer 3 Report

Dear Authors,

Thank you for the interesting research. My remarks are the following:

1. It is highly desirable to add a subsection on the limitations and uncertainties of your study. Some of them have already been given in the manuscript. It seems to me that it would be better if you presented them to the reader in concentrated form (subsection).
2. To what extent can the patterns obtained be extrapolated to the entire surface of the lake? This is an important question, since the depths of the lake and the nature of the currents can influence these patterns. In the Discussion, the authors do not discuss this issue in any way.
3. By the way, what is the depth of the lake at the study site? Appropriate information in the text of the manuscript is required.
4. It is not clear from the manuscript on what data these regularities in the dynamics of the ice cover were made: averaged data from some area of ​​a certain radius relative to the radar, or data collected at a point strictly under the radar? Please clarify this nuance in the manuscript.
5. Have the radar data been spot-checked with field data? Please write about this procedure in the manuscript.
6. Figure 2. What are the units of measurement on the horizontal axes of the graphs?
7. I do not consider the use of phrases "ambient temperature" and "ambient humidity" to be correct. It seems to me that "near-surface air temperature" and "near-surface air humidity", respectively, are more suitable. Please check the text.

Author Response

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Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The authors have now incorporated most of my earlier review comments. I therefore recommend publishing the paper.

Reviewer 2 Report

Thank you for addressing my comments.

Reviewer 3 Report

Thank you for the revision of the manuscript. Good luck.

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.