Development of a UAV-Based Gamma Spectrometry System for Natural Radionuclides and Field Tests at Central Asian Uranium Legacy Sites
Round 1
Reviewer 1 Report
The manuscript documents very well the method and the use of these unmanned aerial vehicles (UAV) equipped with gamma-spectrometry systems for mapping, assessing and monitoring radioactivity.
I believe that the manuscript can be accepted with minor change:
1.Please be careful at the numbering of the references.
2. Because there are many abbreviations in the entire manuscript, please do a list of these abbreviations at the beginning of the manuscript.
Comments for author File: 
Comments.pdf
Author Response
Dear reviewer,
Many thanks for your comments. We have taken your points into account, see attached response sheet, please see the attachment.
Best regards, also on behalf of all co-authors,
C. Kunze
Author Response File: 
Author Response.docx
Reviewer 2 Report
Dear Authors,
I've enjoyed reading your manuscript, I found the overall quality to be good. I have a number comments/questions, which might be somewhat nitpicky, asking about have you considered different UAV designs, did you consider some parameters like foliage cover, and the partially mentioned soil moisture, or did you consider using some low cost/locally probably available technologies. Mostly I found my thoughts to align with yours.
I also have suggestions, I would like you add some details or emphasize something. Like I would like you to consider based on the theoretical or probable effect of soil moisture regarding wether you can compare different areas or measurements at different time directly, because I am not sure you can, and adding details of the test flight parameters, which I feel is missing.
Comments for author File: Comments.pdf
Author Response
Dear reviewer,
Many thanks for your very careful review, comments and useful suggestions. We have taken all your very valuable points into account and believe that you have raised numerous points that have greatly improved the manuscript. Please see the attachment for a detailed response sheet.
Best regards, also on behalf of all co-authors,
C. Kunze
Author Response File: Author Response.docx
Reviewer 3 Report
Although very interesting, I find Introduction and Chapter 2 (Conceptual considerations of UAV-based gamma spectrometry for ULS) too long.
I would expect such a goal: ” (…)the main objective of this paper was to outline the logistical requirements and administrative challenges that have been addressed only in passing by previous authors" rather, as suitable for a review article or book / report chapter.
Instead of summarizing the solutions presented in the literature in too detail, the calibration should be described in more detail. Similarly to other specific information related to the measurements: how long did it take, was it repeatable, does the results depend on the altitude, what is the uncertainty of the measurement, etc.
Please provide details on the calculation of parameters presented in Table 2.
Summing up, I find a subject important from a practical point of view and presented solution useful, however the structure of the article have to be rearranged and more results presented to prove the usefulness of the described system.
Author Response
Dear reviewer,
Many thanks for your careful review and your constructive comments and valuable suggestions. We have taken them into account in the revised version, for details please see the attachment. The point that we could not fully implement concerns the suggested re-structuring, see attached response sheet attached for an explanation. However, we hope that with the additions, clarification and re-arrangements of some of the sub-sections the manuscript should have improved in your sense.
Sincerely yours, also on behalf of all co-authors,
C. Kunze
Author Response File: Author Response.docx
Reviewer 4 Report
The Manuscript ID: remotesensing-1659867 is focused on the experimental use of an unmanned aerial vehicle (UAV) equipped with gamma-spectrometry systems as a novel tool for mapping, assessing and monitoring radioactivity at sites affected by uranium mining and processing and other activities related to enhanced natural radioactivity. Special emphasis is put on the practical conditions of using UAV-based gamma spectrometry in an international context focussing on low- and medium-income countries.
The paper is quite well-organized. It contains some original results and the overall presentation is convincing. The following corrections are recommended before paper publication:
- In general Introduction has a good structure. The introduction should be enriched with a paragraph explaining the correlation between the following sections.
- The authors should ensure the reliability of their study.
- The authors should refer in more detail and in clearly way the advantages of their methodology and summarize possible limitations.
- Please check References according to the journal requirements (numbering, doi).
Author Response
Dear Reviewer,
Many thanks for your careful review and constructive suggestions which we believe have helped to improve the manuscript. We have taken all your comments and suggestions into consideration, please see the attachment for details.
Sincerely yours, also on behalf of all co-authors,
C. Kunze
Author Response File: Author Response.docx
Round 2
Reviewer 3 Report
I am satisfied with the presented version after correction.
