New Remote Sensing Data on the Potential Presence of Permafrost in the Deosai Plateau in the Himalayan Portion of Pakistan
Round 1
Reviewer 1 Report
In my opinion the idea of this paper is interesting enough for pubications but I have to comment a few things which need to be addressed.
First of all I have to say that maybe is somehow difficult for the reader to relate the global warming and climate change with the study. Therefore, I would suggest a modification of the title.
Another thing that I have to mention is the methodology that the authors use to classify the pixels as a lake or a water surface. It is not clear if an index such NDWI is used or the classification have been done without such an index. This has to be clarified.
Lines -->88-90. Please correct the syntax/English language.
Lines -->166-168. Please correct the syntax/English language. Use a verb.
Lines -->179-182. Please correct the syntax/English language.
Line -->253. Please correct Table3 (use space).
Line -->275. Please correct maps.
Lines -->279-282. Please correct the syntax/English language (for each available point).
Line -->294. Please add "and".
Line -->305. A very?.
Lines -->338-341. I think that the related references are missing.
Line -->344. Please use a verb at the last line of conclusions.
Thank you
Author Response
Response to Reviewer 1 Comments
Point 1: I have to say that maybe is soehow difficult for the reader to relate the global warming and climate change with the study. Therefore, I would suggest a modification of the title.
Response 1: Thank you for this comments, we will remove the relation with global warming in the title, and we will cite this potential hypotesis in the § Conclusions.
Point 2: It is not clear if an index such NDWI is used or the classification have been done without such an index. This has to be clarified.
Response 2: Thank you for your comment, we specified better this point in the text, modifying the sentence “On the basis of the photointerpretation of each image and the extraction of water using the indices, a semi-automatic interpretation guaranteed the potential mis-interpretation of water and shadows” as “Comparing the composite RGB images with the NDWI and NDVI incdces for each year, the final lakes boundaries were obtained. This visual interpretation improved the classification based on the indices alone, and guaranteed the potential mis-interpretation of water and shadows”.
Point 3: Lines -->88-90. Please correct the syntax/English language.
Response 3: Thank you, done
Point 4: Lines -->166-168. Please correct the syntax/English language. Use a verb.
Response 4: Thank you, done
Point 5: Lines -->179-182. Please correct the syntax/English language.
Response 5: Thank you, the sentence “ The technical characteristics of the Sentinel-1 constellation, as its revisit time between six and 24 days, the orbital tube diameter of 300 m, providing less noisy interferograms and the freely available without any restrictions for use, can provide a new and powerful tool for monitoring purposes” has been modified as: “The technical characteristics and the freely available use of the Sentinel-1 constellation can provide new and powerful tools for monitoring purposes. Indeed, this two-satellite system offers a revisit time between 6 (at the equator) and 24 days (at higher latitude). Moreover, it is equipped with an orbital tube diameter of 300 m, providing less noisy interferograms”.
Point 6: Line -->253. Please correct Table3 (use space).
Response 6: Thank you, done
Point 7: Line -->275. Please correct maps.
Response 7: Thank you, done
Point 8: Lines -->279-282. Please correct the syntax/English language (for each available point).
Response 8: Thank you, the sentence “ For each point is available a time series with deformations data related to each epoch of observation that can show linear trends with a dispersion of few mm” has been modified as: “The time series with the deformation data, related to each observation, is available for individually point. These series can show linear trends with a dispersion of few millimeters”.
Point 9: Line -->294. Please add "and".
Response 9: Thank you, done
Point 10: Line -->305. A very?.
Response 10: Thank you, checked and modified
Point 11: Lines -->338-341. I think that the related references are missing.
Response 11: We changed the sentence.
Point 12: Line -->344. Please use a verb at the last line of conclusions.
Response 12: Thank you, done
Author Response File: 
Author Response.docx
Reviewer 2 Report
The work is devoted to the study of the environment of the Deosai National Park area, the purpose of which is to support the management of the ecosystem of this park in terms of adaptation to climate change. In particular, the authors carried out monitoring of the land cover and morphological changes in the territory from 1990 to 2019 using remote sensing data from Landsat and ESA Sentinel 1, 2. As a result of long-term analysis, a strong watering of the territory was revealed, according to the authors, it is associated with the presence of permafrost and its degradation due to climate warming.
The strength of the work is to conduct monitoring studies for 30 years with the identification of watering of the territory and, in general, a contribution to the study of the environment of this region.
Of course, as a hypothesis, researchers can talk about the presence of permafrost, but the authors made 2 rather unacceptable mistakes. In this regard, the reviewer has important remarks:
1. In works of this kind related to global warming, there must be a climate justification - climate data on air temperature, precipitation, etc. for a number of years, climate trend.
2. Also, without cryolithological substantiation, determination of the ice content of ground, it is absolutely impossible to talk about thermokarst! The term thermokarst should be completely removed from the article. (Here I repeat that the identification of watering, the appearance of lakes is certainly good, but it is impossible to talk about their thermokarst origin without data on the ice content of the ground, on the lithological composition, this is an important point that needs to be proved and substantiated).
3. It is recommended to provide data on the presence of glaciers. Perhaps the appearance of lakes is associated with their thawing.
For other comments, in Fig. 4 (right map), the authors made an attempt to identify permafrost types according to available global models. Here are recommendations for the technical design of the map - the contours must be made smoother, in view of the fact that in nature all bends have smooth outlines. The same recommendations for Figure 12 (upper part).
Comments for author File: 
Comments.pdf
Author Response
Response to Reviewer 2 Comments
Point 1: In works of this kind related to global warming, there must be a climate justification - climate data on air temperature, precipitation, etc. for a number of years, climate trend.
Response 1: Thank you for this observation. We agree and we think that this is a preliminary study on the potential presence of permafrost in this area. Considering climate data and its change, we cited the paper of Hussain, N.; Ali, S.; Hussain, A.; Ali, S.; Khan, S.W.; Raza, G.; Abbas, Q.; Hussain, I.; Hussain, M. Climate Change Variability Trends and Implications for Freshwater Resources in Pakistan’s Eastern Hindu Kush Region. Pol J Env. Stud 2018, 27, 665–673, doi:10.15244/pjoes/75960. Point 2: Also, without cryolithological substantiation, determination of the ice content of ground, it is absolutely impossible to talk about thermokarst! The term thermokarst should be completely removed from the article. (Here I repeat that the identification of watering, the appearance of lakes is certainly good, but it is impossible to talk about their thermokarst origin without data on the ice content of the ground, on the lithological composition, this is an important point that needs to be proved and substantiated).
Response 2: Thank you for these very clear comments. We are sure that field surveys, drills and collection of soils cores in permafrost are necessary to characterise and know the ground ice content, but with this study we try to suggest, using the multitemporal analysis of surficial landforms, the potential presence of permafrost layer and its changes, starting from these data and existing global permafrost maps. As you suggest, to understand better the purpose of this study that did not want to analyse the permafrost dynamics but only propose its potential presence, we remove the term thermokarst and we used the general term “periglacial landform/lakes”.
Point 3: It is recommended to provide data on the presence of glaciers. Perhaps the appearance of lakes is associated with their thawing.
Response 3: Thank you for this comment. We cited the presence of glaciers and their melting in the § Study area as water supply for the wetlands and small lakes. We specified that the glaciers are very few and small in the Deosai Plateau.
Point 4: in Fig. 4 (right map), the authors made an attempt to identify permafrost types according to available global models. Here are recommendations for the technical design of the map - the contours must be made smoother, in view of the fact that in nature all bends have smooth outlines. The same recommendations for Figure 12 (upper part).
Response 4: Thank you, we smoothed the polygons in figures 4 and 12, as suggested.
Author Response File: Author Response.docx
Reviewer 3 Report
Because I am not a specialist in remote sensing, but in permafrost, in my opinion, I will not asses the issue of methodology and how to carry out and analyze the measurements, they seem to be done correctly, however.
More important, however, is what has been measured. It should be emphasized here that the article deals with the reaction of the earth's surface to the degradation of underground ice, which is located at a relatively small depth below the earth's surface. Therefore, this article deals with the variability of the topography of the earth and the hydrological system under the influence of ground ice melting. This is not the same as changing the permafrost range. Permafrost has a different, broader specificity, it can cover wider areas and lie deeper than underground ice. For a proper understanding of this work, such a supplement is necessary. One can get the impression that the authors are good specialists in the field of methodology, but not in the field of permafrost. I have included other comments in the attached text.
Comments for author File: Comments.pdf
Author Response
Response to Reviewer 3 Comments
Point 1: In order for the article to have a scientific value, it is necessary not only to perform and analyze the measurements and their quantitative characteristics indicating variability. It is necessary to present the research problem well, which is missing here, because the authors do not seem to have sufficient knowledge about permafrost. In fact, therefore, they do not characterize permafrost, but only the variability of the underground ice occurring in the study area. In order for the work to have a scientific value, it is necessary to focus not on the methodology and its accuracy, but on the proper presentation of the subject of research - permafrost. However, this is missing from the article.
Response 1: Thank you for your comment. This study originated from the observation of changes in the number and extension of lakes and wetlands in the Deosai Plateau, an area that we are studying from several years from remote sensing data and in the field, when possible.
One of the main characteristic of this area is the presence of water fbodies and wetlands during the summer season and their variability. Indeed, observing the time series of satellite images, it has been noted that the lakes appear and disappear in different areas and that their number and extent have weakly decreased over time. Instead, there has been an increase in the extension of wetlands. Furthermore, the use of interferometric data has highlighted the presence of variations in the speed of vertical movement of the ground, in particular negative (lowering) in an area where there is a large wetland area around a depressed circular shape, clearly visible in high resolution images (the area of Black Hole). Since there were no studies in this sector of Pakistan relating to the presence and characteristics of permafrost, the global maps on the presence of permafrost existing in the literature were acquired, and are proposed in the article as comparison. It emerges that the plateau is affected by the presence of a discontinuous permafrost also in the sector we have studied, and that therefore this morphology may be linked to a periglacial landform. The study therefore hypothesizes that the variations of number, and surfaces of lakes and wetlands can be due to a variability of the permafrost, trying to stimulate the interest in the necessary in-depth studies in the field with the direct measures and analisys of soils and lithologies.
We think that the value of this study was therefore to have extracted new original data on the Deosai plateau, an extremely important area from an ecological and biodiversity point of view, in which the effects of global warming can compromise its integrity and are not known.
We added one sentence in the conclusions to clarify this point.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
I suggest the publication of the article.
The comments have been well addressed and the paper is now much more appropriate for publication.
Reviewer 2 Report
Review №2
The work has been sufficiently improved, taking into account the suggestions and comments in review No. 1. However, for some reason, the authors decided to integrate climate data in subsequent works, although in my opinion this is an important component of the study.
In general, the study is presented quite well, new interesting results are presented, the work can be recommended for publication.
Comments for author File: Comments.pdf
