Remote Sensing and Environmental Monitoring Analysis of Pigment Migrations in Cave of Altamira’s Prehistoric Paintings
, Alfredo Prada 3, Francisco GarcÃa 4,*, Carmen De Las Heras 3 and Pilar Fatás 3Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsPlease improve your work by taking into account the deficiencies given in the attachment.
Comments for author File: 
Comments.pdf
Author Response
Dear Reviewers,
We would like to thank the editor for the time and effort to gather insightful reviews for our submission. We also would like to thank the editor and the reviewers for their valuable comments on the manuscript that help significantly improve our paper's quality in this revision.
Based on the provided set of reviews, we have carefully revised our paper. The details of our revision are described below. We hope that the reviewers find the changes satisfactory, and the revised manuscript successfully addresses the comments of the reviewers.
The revised manuscript is submitted to the MDPI submission website, and we attach this letter that discusses our changes made with respect to each of the comments. Again, these reviews were very instructive, and we would like to thank the reviewers once again for their time to review the paper.
You can find the point-by-point answers in the attached document
Best regards,
The authors
Author Response File: Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThis article describes in a detailed way the design of a complex methodology for the creation of an integrated 3D model by coupling high-frequency GPR, GNSS, TLS and high-resolution photogrammetry for the microclimatic analysis of the renowned Cave of Altamira. Specifically, this interesting work aims to depict the water flow and its effects on the conservation of paintings by evaluating the phenomena of local damage due to moisture and dripping as degradation agents that trigger processes of pigment migration. The work is structured with care and effort, with a big load of details. The bibliography is well designed and provides a detailed literature collection, not only to support methodological explanations but also to help the reader to have an overview of Altamira's cave characterization and the state of the art about its preservation and analogous applications on similar case studies. The methodology is deemed suitable and effective in overcoming several necessities related to the challenging conditions of this site (for example, the necessity to conduct a totally non-destructive analytical campaign, avoiding any direct contact with the painted surfaces). The authors have, therefore, devised a procedure that consists of various steps, some of which are also ingenious engineering works (for example, the sliders or the validation with witnesses) aimed at carrying out the analyses in the particular conditions of a protected underground environment. The designed approach allows clear identification of the damage factors, visualized in three-dimensional maps of the hydrography of the site, which can be used for the subsequent safety of the precious polychrome surfaces. The reading is smooth and only a few passages have repetitions or remain slightly abstract or theoretical to the reader.
Following is a list of points that emerged as improvable:
- The title is slightly confusing because of the specific indication of microbial populations analysis, which doesn't correspond with the contents that is instead mainly dedicated to the moisture-connected damage of pigment migration.
- I would reduce the number of keywords to the ones that contain more specific terms.
- I would shorten slightly the introductory paragraph (from the beginning till line 51, which is a bit repeated).
- Does the 'large red claviform' term indicate a figure of the drawing? Can it be more clearly individuated in the picture or, otherwise, more explained in the text?
- The 3DTLS acronym that stays for 3D Terrestrial Laser Scanner shall be defined, as well as GNSS, which is first used in the text as the only acronym and then explained in an extended version. Other acronyms of common use, like UAV, necessitate less of the extended specification so they can stay so.
- I was curious about the seasons of the GPR campaigns. Additionally, it is interesting to understand, with more specification, how these heterogeneous data were integrated/combined (2023 campaign and earlier 2D records ).
- Figure 2a: In the picture, several points marked as ALT (plus number) are shown on the map but are not used or mentioned in the text. I would remove them from the picture, or alternatively, I would briefly explain how the other ALTs have also been employed in the work.
Lines 166-167: It is mentioned here that among the aims of the work is also the understanding of the interaction with climatic variation and anthropogenic activities, which is also referred to later on in lines 635-636, but these aspects are not described in the text. Could it be possible to add information about these aspects? Otherwise, I would suggest mentioning them more clearly as future developments of the work (as it is done in Conclusion for the climatic aspect).
- About resolution/ accuracy of the GPR method in localizing the reflectors/elements of the system, if possible I would add more details.
- Figure 2c: the nature of some of the layers of the schematic stratigraphy needs to be clarified (orange and wedge layers). The text report references but a short definition of the units can be useful if this could be readable directly in the text
- In Fig 3, the scale and the indication of the B subpicture are missing.
- Paragraph 2.2 and Figure 4: The paragraph could be a bit more explicative, and the figure is somehow more complex than the written content. For example, the 3D Terrestrial Laser Scanning part could be maybe more thoroughly explained. The hydrological analysis in GIS could also be clearly shown in the graph?
- Line 205: The method used in [31] could be briefly summarized in the text to facilitate easier reading.
- Lines 205-206: this point's text needs to be clarified.
- Concerning the photogrammetric campaign that was done in 2014, has the cave changed so much to make necessary a new campaign? For example, I imagine that the extracted orthoimage shows the pigment conditions relative to that period. So, can the detachments, fractures, erosion or other physical alteration processes have slightly changed the micromorphology of the Ceiling model? I imagine that the data from 2014 can be used with no relevant problems, but maybe a short statement can be added about it, stating that this doesn't affect either the hydrological calculation or the understanding of the processes of alteration.
- Figure 6: I would also add a scale here.
- Paragraph 2.3.4: the paragraph is useful and interesting, but the generic part could be reduced (lines 325-352) or may be integrated with the previous paragraph 2.3.2.
-Line 363: I would add a reference for the software RADAN.
-From Paragraph 2.4, the text becomes a bit less effective in explaining practically how the inputs are integrated and outputs are generated.
Paragraph 2.4: I would add a few more details on the input data and how the Strahler method has been applied. Maybe graphical support for the workflow or a bit more discursive explanation can help the statements from lines 407-425, which are a bit abstract. I would also add the indication of the QGIS version used and an additional specification of which is the first version that implements this analytical function.
- Fig. 7: it looks like the legend in the map doesn't correspond to all the symbols used in the map. The polygons for the active drip points(green polygons with transparent filling) are instead represented by a different green-filled polygon.
- I would add a reference about geophysical prospecting studies from 544-550.
Besides these points, I find the article interesting and suitable for publication.
Comments on the Quality of English Language
The writing style is clear and well-organized. Only in a few points are some statements less straightforward or contain a few mistakes. The following are the points marked:
In the abstract, lines 24-25, I would change the wording slightly to ' pigment and other substances migration'.
- The ceiling is very often written with the first capital letter and, at some points, in lowercase. I suggest uniformizing the way of mentioning it, in both cases, whether it is used with or without the specification of the Polychrome Hall.
- The word 'feature' is sometimes used in points where perhaps synonyms would work better, for example, in lines 71 and 78.
Line 124: The use of the term 'sign' is not clear at that point (it is more clearly used later, for example, in line 181).
- Lines 149-151: the terms 'emphasized' and then 'emphasizing' sound like a repetition in the same sentence. It is suggested to replace one of the two with a synonym.
- Line 205-207: the statement needs to be clarified.
- Line 209: 'next 5 cm interval profiling'- the 'next' is unclear.
- In picture 4, the word 'georeferencing' is wrongly spelt into 'georeferencing'.
-Line 266: '…is lower than the 900 and 400…..'(I would suggest adding 'with' – 'lower than with the').
-Line 291: the 'antenna air-coupled' wording order is not clear and can be mistaken.
- In line 296, I would replace the colon with a few words.
- Line 498: a ( shall be removed).
- Line 544: ATL instead of ALT
- Lines 578 and 579: some deleted commas still have the review sign.
- Line 593-610: here, subparagraph numbering or a different kind of heading may be added.
Author Response
Dear Reviewers,
We would like to thank the editor for the time and effort to gather insightful reviews for our submission. We also would like to thank the editor and the reviewers for their valuable comments on the manuscript that help significantly improve our paper's quality in this revision.
Based on the provided set of reviews, we have carefully revised our paper. The details of our revision are described below. We hope that the reviewers find the changes satisfactory, and the revised manuscript successfully addresses the comments of the reviewers.
The revised manuscript is submitted to the MDPI submission website, and we attach this letter that discusses our changes made with respect to each of the comments. Again, these reviews were very instructive, and we would like to thank the reviewers once again for their time to review the paper.
You can find the point-by-point answers in the attached document
Best regards,
The authors
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsI would like to thank the authors for taking into account the necessary corrections and suggestions to improve the article.
