Applicability of the MultiTemporal Coherence Approach to Sentinel-1 for the Detection and Delineation of Burnt Areas in the Context of the Copernicus Emergency Management Service
Round 1
Reviewer 1 Report
Summary Comments:
The paper deals with the use of Sentinel-1 images for the delineation of burned areas,through the MultiTemporal Coherence (MTC) technique. The subject is interesting and the text was in general well written. The methods are appropriate. However, some minor modifications along the manuscript may make the content more understandable to readers. I briefly highlight some points that can be improved:
- In the Introduction, the relevance of the study could be better justified. Why is this study important? What are the differences compared to other works already published? In addition, the paper's objectives were missing at the end of the
Introduction.
- More information on the study area could be provided, such as country, region, climate, etc.
- Some sentences of the Results (lines 158-160, 175-176, 179-162) could be reallocated to the Discussion section.
- The Discussion section could be amplified, comparing the results with other
studies in the literature.
Specific Comments:
Line 17: In the Abstract, add the full meaning of the abbreviation EMS.
Lines 38-42: The sentence is too long. Consider to divide it. Suggestion: The early warning and monitoring component consists of three different systems, the European Flood Awareness System (EFAS) [2], the European Forest Fire Information System (EFFIS) [3] and the European Drought Observatory (EDO) [4]. EFAS provides information about monitoring and forecasting floods across Europe, while EFFIS and EDO deal with forest fires and droughts, respectively, and their ecological impacts in Europe, the Middle East and North Africa.
Line 42: this three ---- these three
Lines 49-52: Suggestion: The Copernicus EMS Mapping includes a Validation module that, activated by the European Commission, takes as input the outputs of the Rapid Mapping and Risk and Recovery Mapping products and validates them on a sample basis taking the Validation protocol created by the Joint Research Center (JRC) as reference [5,6].
Lines 65-66: Consider rephrasing: The first ones Sentinel-1 images were used to obtain the fire delineation over the study area, while the others Sentinel-2 and SPOT 6 images were used as reference data to validate the result obtained.
Lines 71-74: State in which processing step the SRTM data was used. Also, why did you use the ~ 90 m DTM to process the optical data (10 m)?
Lines 98-99: Avoid using the term band to designate the colors of an RGB composite as this can confuse with the bands of a multispectral sensor. Rewrite this sentence. Example: t1 and t2 amplitude were assigned to the red and green colors, respectively.
Line 148: Replace The following figure 3 . Also, since more data was
used besides Sentinel-2 to construct the reference data, it would be desirable to add at the end of the phrase "and ancillary data". Same for the caption of figure 3.
Line 151: Replace The following figure 4 .
Line 155: Consider adding an article before the word results .
Line 166: Add a comma after In this table
Line 169: It is not clear to me whether the union of crisis information is the union of the Sentinel-1 burned area with the reference burned area. Try rephrasing the sentence for clarity.
Line 188: Consider replacing
Lines 201-203: Suggestion: However, it should be highlighted that similar limitations are present when using optical imagery to delineate burnt areas in sparse vegetation.
Lines 204-205: What validation criterion is this statement based on? Try to quantify the comparisons.
Author Response
Response to Reviewer 1 Comments
Point 1: In the Introduction, the relevance of the study could be better justified. Why is this study important? What are the differences compared to other works already published? In addition, the paper's objectives were missing at the end of the Introduction
Response 1: More info added. Please check if it is sufficient.
Point 2: More information on the study area could be provided, such as country, region, climate, etc.
Response 2: Results of the Copernicus EMS Validation Service are not public and due to confidentiality restrictions, we are not allowed to give more details about the area. The JRC allowed us to make the figures with coordinates but would request us not to give more details about it.
Point 3: Some sentences of the Results (lines 158-160, 175-176, 179-162) could be reallocated to the Discussion section
Response 3: Done
Point 4: The Discussion section could be amplified, comparing the results with other studies in the literature.
Response 4: Done.
Point 5: Line 17: In the Abstract, add the full meaning of the abbreviation EMS.
Response 5: Done
Point 6: Lines 38-42: The sentence is too long. Consider to divide it. Suggestion: The early warning and monitoring component consists of three different systems, the European Flood Awareness System (EFAS) [2], the European Forest Fire Information System (EFFIS) [3] and the European Drought Observatory (EDO) [4]. EFAS provides information about monitoring and forecasting floods across Europe, while EFFIS and EDO deal with forest fires and droughts, respectively, and their ecological impacts in Europe, the Middle East and North Africa.
Response 6: Done
Point 7: Line 42: this three - these three
Response 7: Done
Point 8: Lines 49-52: Suggestion: The Copernicus EMS Mapping includes a Validation module that, activated by the European Commission, takes as input the outputs of the Rapid Mapping and Risk and Recovery Mapping products and validates them on a sample basis taking the Validation protocol created by the Joint Research Center (JRC) as reference [5,6]
Response 8: Added
Point 9: Lines 65-66: Consider rephrasing: The first ones Sentinel-1 images were used to obtain the fire delineation over the study area, while the others Sentinel-2 and SPOT 6 images were used as reference data to validate the result obtained
Response 9: Added
Point 10: Lines 71-74: State in which processing step the SRTM data was used. Also, why did you use the ~ 90 m DTM to process the optical data (10 m)
Response 10: Answered. Please check the clarification is enough.
Point 11: Lines 98-99: Avoid using the term band to designate the colors of an RGB composite as this can confuse with the bands of a multispectral sensor. Rewrite this sentence. Example: t1 and t2 amplitude were assigned to the red and green colors, respectively
Response 11: Corrected.
Point 12: Line 148: Replace The following figure 3 . Also, since more data was used besides Sentinel-2 to construct the reference data, it would be desirable to add at the end of the phrase "and ancillary data". Same for the caption of figure 3.
Response 12: Corrected.
Point 13: Line 151: Replace The following figure 4.
Response 13: Corrected.
Point 14: Line 155: Consider adding an article before the word results
Response 14: Added.
Point 15: Line 166: Add a comma after In this table
Response 15: Added.
Point 16: Line 169: It is not clear to me whether the union of crisis information is the union of the Sentinel-1 burned area with the reference burned area. Try rephrasing the sentence for clarity
Response 16: Added.
Point 17 Line 188: Consider replacing “as” by “like”
Response 17: Done.
Point 18: Lines 201-203: Suggestion: However, it should be highlighted that similar limitations are present when using optical imagery to delineate burnt areas in sparse vegetation.
Response 18: Done.
Point 19: Lines 204-205: What validation criterion is this statement based on? Try to quantify the comparisons.
Response 19: Clarification added.
Reviewer 2 Report
The paper aims at comparing Sentinel-1 and Sentinel-2 for the detection and delineation of three forest fires in the context of Copernicus EMS. The topic has a relevant interest and a potential applicability. However, the paper should be further improved as it has several caveheats that are detailed below.
Point 1: The in the introduction should be completely rewritten here are some tips that might be considered:
o how do we traditionally measure delineate forest fires?
o what are the benefits of using SAR data?
o are there studies that have previously analysed the delimitation of fires using radar data? Do they have good performance?
o aims of the work should be included
Point 2: The map of the study area should be located after the first paragraph. o Lines 59-61: please describe the study area: where is located and characteristics, include a map of the study area here. What type of mediterranean forests (at least describe with the forest national map: what are the main species? all of the fire was forested lands?) was affected by fire?
Point 3: Line 62-65 the aim of the study must be in the introduction
Point 4: Line 72 please specify spatial resolution in meters
Point 5: Line 70-72 have you done this preprocessing or it is just the preprocess made it by ESA? This should be clearly explained
Point 6: Line 80-83: the process should be more in deep explained
Point 7: Line 92: this is not methodology maybe better in discussion?
Point 8: I do not understand why some words are in bold. Please clarify along the manuscript
Point 9: Lines 94-96: how do you calculated coherence?
Point 10: Lines 98-104: this is part objectives (introduction) and part results
Point 11: Lines 107-146: this should be linked with the previous paragraphs
Point 12: Lines 121-122: this is a specific aim of your work? Please clarify. This should not be in methodology
Point 13: Line 127: why do you use the index BAI when the traditional ones are NBR and dNBR to estimate fire severity as the difference between pre-fire and pst-fire NBR values? Reference 13 is in wrong format. Are there other works that use this index with sentinel-2, Landsat etc.? Iwould certainly encourage to compare with other more common burned indexes so the applicability increases.
Point 14: Line 134: this must be clarified how do you edit it? validation data is one of the most relevant parts in a work and this part should be clearly explained
Point 15: Line 134: which classification? the index dBAI create by Sentinel-2 is not a classification
Point 16: Line 137: clearify do you use SPOT6 as ancilliary data or not
Point 17 Line 144: you can always downscalling the sample this is not generally a problem, but it is the lack of pre-fire data from SPOT6 If you are not using SPOT6 references to the data should be deleted
Point 18: Line 145: this sentence should be integrated in the text
Point 19: Figure 2: figure 2 clarifyes a little bit things but methodology should be clearly explained in the text. Furthermore, how do you performed manual refinement? How did you do in-situ burnt area delineation?
Point 20: 148-150 this is not results is methodology/study area
Point 21: Figure 3: this cartography, which should be in the introduction, must be improved: north and scale in the left map, where are we? Please at least the name of the country, island…; what colour composition are you using with Sentinel-2? Try to make it a little bit bigger the map on the right it is almost impossible to see some burned areas.
Point 22: 151-154 this is just the pre-processing not the complete results. You need to explain the things we can see in the cartography, which should be improved (at least north and scale).
Point 23: Line 16 [1414] is this [14]?
Point 24: Figure 5: all the cartography should be improved. I would recommend to use a GIS software to do it. Please if Figure 5 have 4 parts this should be in the same page.
Point 25: Line 168: are these validations or training values? The classification is not explained properly and neither the validation procedures.
Point 26: Line 169: you haven’t talked about this before can you include it in the cartography?
Point 27: Lines 177-184: this should be in the discussion section.
Point 28: Discussion section should be considered rewritten there is no even one reference in discussion where the main aim of this part is compare with other results within the bibliography.
Point 29: Conclusion: you do not refer to your specific results founded in the paper. Paragraphs 2 and 3 are kind of general comments which can be either in the introduction or here but you really need to summarize your findings.
Point 30: The number of references is too short and most of them are not forest MDPI style. This should be increased along the paper specially within the introduction and discussion sections.
Point 31: The paper is too small, only 10 pages including acknowledgements, abbreviations and references. I would certainly encourage authors to make it a little bit bigger (at least something like 5 more pages).
Author Response
Response to Reviewer 2 Comments
Point 1: The in the introduction should be completely rewritten here are some tips that might be considered:
o how do we traditionally measure delineate forest fires?
o what are the benefits of using SAR data?
o are there studies that have previously analysed the delimitation of fires using radar data? Do they have good performance?
o aims of the work should be included
Response 1: Corrections have been made. Please checks whether they are sufficient.
Point 2: The map of the study area should be located after the first paragraph. o Lines 59-61: please describe the study area: where is located and characteristics, include a map of the study area here. What type of mediterranean forests (at least describe with the forest national map: what are the main species? all of the fire was forested lands?) was affected by fire?
Response 2: I have included a figure with the location of the study area. However, results of the Copernicus EMS Validation Service are not public and due to confidentiality restrictions, we are not allowed to give more details about the area. The JRC allowed us to make the figures with coordinates but requested us not to give more details about it.
Point 3: Line 62-65 the aim of the study must be in the introduction
Response 3: Done, please check whether it has been sufficient.
Point 4: Line 72 please specify spatial resolution in meters
Response 4: Done
Point 5: Line 70-72 have you done this preprocessing or it is just the preprocess made it by ESA? This should be clearly explained
Response 5: Done
Point 6: Line 80-83: the process should be more in deep explained
Response 6: Done
Point 7: Line 92: this is not methodology maybe better in discussion?
Response 7: It has been moved to the Discussion, with some amendments.
Point 8: I do not understand why some words are in bold. Please clarify along the manuscript
Response 8: Words in bold were meant to help the reading of the document, by separating the different parts that were meant to be explained. However, the fact that they were not understood proves that they do not ease the reading, and have been therefore deleted.
Point 9: Lines 94-96: how do you calculated coherence?
Response 9: More information has been added.
Point 10: Lines 98-104: this is part objectives (introduction) and part results
Response 10: This part has been moved to the introduction and amendments have been included.
Point 11: Lines 107-146: this should be linked with the previous paragraphs
Response 11: This part has been changed.
Point 12: Lines 121-122: this is a specific aim of your work? Please clarify. This should not be in methodology
Response 12: This part has been moved to the Results.
Point 13: Line 127: why do you use the index BAI when the traditional ones are NBR and dNBR to estimate fire severity as the difference between pre-fire and pst-fire NBR values? Reference 13 is in wrong format. Are there other works that use this index with sentinel-2, Landsat etc.? Iwould certainly encourage to compare with other more common burned indexes so the applicability increases.
Response 13: Although the NRB is more commonly used, in the scope of the Copernicus EMS, and given that optical VHR images are generally prioritised (that usually include only 4 bands), the BAI is preferred. Even if we could have created the reference data using NBR, we believe that the errors caused by the worse performance of BAI compared to NBR are overcome with the use of ancillary data. It has to be pointed that in this specific case the performance of the BAI was extremely good and, when compared to the SPOT 6 no major errors were found.
Point 14: Line 134: this must be clarified how do you edit it? validation data is one of
the most relevant parts in a work and this part should be clearly explained
Response 14: Added.
Point 15: Line 134: which classification? the index dBAI create by Sentinel-2 is not a classification
Response 15: This part has been clarified.
Point 16: Line 137: clearify do you use SPOT6 as ancilliary data or not
Response 16: This part has been clarified.
Point 17 Line 144: you can always downscalling the sample this is not generally a problem, but it is the lack of pre-fire data from SPOT6 If you are not using SPOT6 references to the data should be deleted
Response 17: This part has been rewritten.
Point 18: Line 145: this sentence should be integrated in the text
Response 18: Done.
Point 19: Figure 2: figure 2 clarifyes a little bit things but methodology should be clearly explained in the text. Furthermore, how do you performed manual refinement? How did you do in-situ burnt area delineation?
Response 19: Clarification added.
Point 20: 148-150 this is not results is methodology/study area
Response 20: This part has been moved. Please check its new location.
Point 21: Figure 3: this cartography, which should be in the introduction, must be improved: north and scale in the left map, where are we? Please at least the name of the country, island…; what colour composition are you using with Sentinel-2? Try to make it a little bit bigger the map on the right it is almost impossible to see some burned areas.
Response 21: The figure has been changed to increase its readability. Regarding the name of the country, please check Response 2.
Point 22: 151-154 this is just the pre-processing not the complete results. You need to explain the things we can see in the cartography, which should be improved (at least north and scale).
Response 22: More information has been added explaining the figure.
Point 23: Line 16 [1414] is this [14]?
Response 23: Yes. There was a problem with references, now corrected.
Point 24: Figure 5: all the cartography should be improved. I would recommend to use a GIS software to do it. Please if Figure 5 have 4 parts this should be in the same page.
Response 24: The figure has been improved. Paging has been changed so four parts of the figure are in the same page.
Point 25: Line 168: are these validations or training values? The classification is not explained properly and neither the validation procedures.
Response 25: More information regarding the validation approach has been included in the Materials and Methods section. The paper has been mostly rewritten, please check if now it is clear.
Point 26: Line 169: you haven’t talked about this before can you include it in the cartography?
Response 26: The validation approach has been explained in the Materials and Methods. I’m not sure what is meant with “can you include it in the cartography”.
Point 27: Lines 177-184: this should be in the discussion section.
Response 27: Moved.
Point 28: Discussion section should be considered rewritten there is no even one reference in discussion where the main aim of this part is compare with other results within the bibliography.
Response 28: The figure has been improved. Paging has been changed so four parts of the figure are in the same page.
Point 29: Conclusion: you do not refer to your specific results founded in the paper. Paragraphs 2 and 3 are kind of general comments which can be either in the introduction or here but you really need to summarize your findings.
Response 29: The figure has been improved. Paging has been changed so four parts of the figure are in the same page.
Point 30: The number of references is too short and most of them are not forest MDPI style. This should be increased along the paper specially within the introduction and discussion sections.
Response 30: The figure has been improved. Paging has been changed so four parts of the figure are in the same page
Point 31: The paper is too small, only 10 pages including acknowledgements, abbreviations and references. I would certainly encourage authors to make it a little bit bigger (at least something like 5 more pages).
Response 31: Although initially the study was presented as Paper, it was afterwards changed into Letter due to its length, which as you say was too short. However, the modifications have extended it to 15 pages. Please consider whether it was enough.
Reviewer 3 Report
Review: remotesensing-594398
Manuscript Number: remotesensing-594398
Title: Applicability of the MultiTemporal Coherence approach to Sentinel-1 for the detection and delineation of forest fires in the context of Copernicus EMS
General remarks
This study (Letter) provided methods, results, and discussion are potentially useful for science and society. Thus, I will be happy to recommend it for possible publication in the journal of Remote Sensing after Minor revision from the authors.
Detailed comments
Title
Write the full form of the EMS.
Abstract
Line 17: Write full form of the EMS Add one line about the study area. Lack of some specific results within the abstract, suggest to provide some specific results of the study, and its importance for science and society.
Keywords
Add one keyword about the study area. Introduction
The overall structure and brief write-up of the Introduction section are fine.
Materials and Methods There are lacks of site descriptions, suggest to add a brief description of the study area, adding with geographical locations (latitude, longitude), climatic scenarios and so on. Without details of the study area, readers will confuse and it impacts the overall readership of the paper and its applicability. Add a clear study area map including the name of the country and study area, then we know which area covered by the study of the globe. Or add the name of the country and study area in figure 3, as well as DEM map for clear elevation gradient. Others descriptions of the applied methods and data of the study are fine. Figure 1 and the workflow of the study in figure 2 are presented perfectly. Results Line 160: [1414]? It is reference number 14? Correct it. Discussion The discussion is written very well, short and fine. Conclusions The conclusions presented a good way. Suggest merging three-paragraph within a paragraph.
Supplementary Materials:
Lines: 232 to 241: As a reviewer, I haven’t found such supplementary materials (Table 3 and 4; Figure 6, 7, 8, and 9) in the website for review it. Thus, I will be happy to see those documents before final acceptance of the manuscript. Additionally, also authors did not mention any details about those supplementary documents within the main text of the manuscript, if there have such supplementary materials please code appropriate way in the main text and provide it for review as well.
Author Response
Response to Reviewer 3 Comments
Point 1: Write the full form of the EMS.
Response 1: Added
Point 2: Line 17: Write full form of the EMS Add one line about the study area. Lack of some specific results within the abstract, suggest to provide some specific results of the study, and its importance for science and society.
Response 2: Added the full form and the acronym of EMS. More information about the study area is also added. However, the name cannot be included due to confidentiality issues: the results of the Copernicus EMS are not public and the JRC has only allowed us to include the coordinates in Figure 3. A summary of main findings has been included.
Point 3: Add one keyword about the study area.
Response 3: As I said before, due to confidentiality issues, we cannot specify more. However, I have added two words.
Point 4: Materials and Methods There are lacks of site descriptions, suggest to add a brief description of the study area, adding with geographical locations (latitude, longitude), climatic scenarios and so on. Without details of the study area, readers will confuse and it impacts the overall readership of the paper and its applicability. Add a clear study area map including the name of the country and study area, then we know which area covered by the study of the globe. Or add the name of the country and study area in figure 3, as well as DEM map for clear elevation gradient. Others descriptions of the applied methods and data of the study are fine. Figure 1 and the workflow of the study in figure 2 are presented perfectly.
Response 4: Again, we are not allowed to give more details regarding the study area I have added some more information but I am afraid we are not allowed to give more. I have changed the figures and included coordinates in all of the, I have included a DEM has been included with the post-event Sentinel-2 overlaying it to give an idea of the elevation. However, more info has been included in the text.
Point 5: Results Line 160: [1414]? It is reference number 14? Correct it.
Response 5: Corrected.
Point 6: Discussion The discussion is written very well, short and fine.
Response 6: Thank you very much. Following recommendations from other reviewers, more info has been added.
Point 7: Conclusions The conclusions presented a good way. Suggest merging three-paragraph within a paragraph.
Response 7: Thank you. Unless considered totally necessary, we believe that separating the paragraphs allows having an easier view of the main points we want to highlight.
Point 8: Supplementary Materials: Lines: 232 to 241: As a reviewer, I haven’t found such supplementary materials (Table 3 and 4; Figure 6, 7, 8, and 9) in the website for review it. Thus, I will be happy to see those documents before final acceptance of the manuscript. Additionally, also authors did not mention any details about those supplementary documents within the main text of the manuscript, if there have such supplementary materials please code appropriate way in the main text and provide it for review as well.
Response 8: There was a problem in the references, which is now corrected.
Round 2
Reviewer 2 Report
I consider that the majority of observations have adequately considered by the authors in the new version of the manuscript, and I thank the authors for the performed changes.
I believe, in addition, that the comments of the other reviewers have contributed to greatly improve the article. However, I do have several changes that should be made by the authors before publication:
Lines 17-19: The sentence “Results of…” should be either deleted or transferred and properly included to line 31.
Lines 24-26: The sentence “Several studies…” should be rewritten or deleted. Furthermore, It is not frequent to include references in the abstract.
Line 94: I will encourage to change “radar” to sar data all over the manuscript.
Line 99: the assumption of “are expected to increase in number and intensity in coming years” requires a citation.
Line 128: Revise Donezar, U et al citation
Line 134-135: please consider rewriting the sentence, concretely “but wchich also”
Line 138-139: I would suggest to delete “shows the location of the study area” as it is already in the figure title.
Line 159-162: consider rewriting/reviewing this sentence as it is not clearly understandable.
Line 165: why did you not pre-process Sentinel-2 images to BOA using sen2cor for example? I consider this should be clarified in the text considering your specific application.
Lines 174-177: please provide references to the processing performed.
Line 182: please specify the default values. Furthermore delete “suggested by the software” and cite who or whose defined those values.
Line 182-183: have you published those previous experiences? Are there comparable with other studies? Please, clarify. The same for lines 188-189.
Line 271-273: “Once the processing of images until the creation” Consider rewriting this sentence.
Line 274: please specify “small size” with the specific value
Line 275: which past experiences? Have you published it?
Line 289: I will suggest to briefly describe the number and type of combinations in the text.
Line 332: consider citing after “its applicability”
Line 350-352: please consider rewriting “for those areas where doubts regarding the presence of fire were doubtful”
Line 377: delete and “color and while”. Revise English across the manuscript.
Line 424: please specify which variables
Line 434-435: “even more” do you mean even though?
Line 440-457: the sentence that starts with “In all …” should be placed in the title of Figure 7. The authors should write at least a brief paragraph describing figure 7 (area in each classification, presence of small polygons, differences etc.). If a figure is not described is because it is not needed in the manuscript so either include a better description (desirable) or delete it. The description in figure 8 is much better for example.
Line 476-477: do you create the classification using both sentinel-1 and the reference burned area created by Sentinel-2 data? Please clarify.
Line 474: area of interest it is only described in the results but not in the methodology. Please include it in the methodology section as it is hard to understand the difference between OA and OAu. Furthermore Ou and Cu refers to the overall accuracy or to the AOI?
There have been three questions which were not addressed or only partially addressed by the authors from my previous revision. I would certainly encourage the authors to perform those changes:
Point 28: Discussion section should be considered rewritten there is no even one reference in discussion where the main aim of this part is compare with other results within the bibliography.
Response 28: The figure has been improved. Paging has been changed so four parts of the figure are in the same page.
Point 28 has only been partially addressed. There should be more references in the discussion and compare your results with the generated by other authors. For example in lines 520-522:
Best results were obtained using the combination of the MTC derived from Ascending and Descending modes together, independent of the polarization used (cite). This result seems to indicate that combining Ascending and Descending images minimises the effect of the topography (cite). Are these findings similar to other studies?
Point 29: Conclusion: you do not refer to your specific results founded in the paper. Paragraphs 2 and 3 are kind of general comments which can be either in the introduction or here but you really need to summarize your findings.
Response 29: The figure has been improved. Paging has been changed so four parts of the figure are in the same page.
This point has not been addressed. Specific results about the classification etc. should be included in the conclusion.
Point 30: The number of references is too short and most of them are not forest MDPI style. This should be increased along the paper specially within the introduction and discussion sections.
Response 30: The figure has been improved. Paging has been changed so four parts of the figure are in the same page
Please review carefully all the references at some of them are wrongly cited (see reference 1 as example) “Available under request…”?
The length of the paper it is now ok for me.
Author Response
Response to Reviewer 2 Comments
Point 1: Lines 17-19: The sentence “Results of…” should be either deleted or transferred and properly included to line 31.
Response 1: Done.
Point 2: Lines 24-26: The sentence “Several studies…” should be rewritten or deleted. Furthermore, It is not frequent to include references in the abstract.
Response 2: Done.
Point 3: Line 94: I will encourage to change “radar” to sar data all over the manuscript.
Response 3: Done.
Point 4: Line 89: the assumption of “are expected to increase in number and intensity in coming years” requires a citation.
Response 4: Done
Point 5: Line 128: Revise Donezar, U et al citation
Response 5: Done
Point 6: Line 134-135: please consider rewriting the sentence, concretely “but wchich also”
Response 6: Done
Point 7: Line 138-139: I would suggest to delete “shows the location of the study area” as it is already in the figure title.
Response 7: Done.
Point 8: Line 159-162: consider rewriting/reviewing this sentence as it is not clearly understandable.
Response 8: Done.
Point 9: Line 165: why did you not pre-process Sentinel-2 images to BOA using sen2cor for example? I consider this should be clarified in the text considering your specific application.
Response 9: Sorry. The S-2 images were indeed corrected as they were acquired in Level 1C. However, they could not be corrected in SNAP due to a bug on the software at that moment and ERDAS and the “classical” way had to be followed.
Point 10: Lines 174-177: please provide references to the processing performed.
Response 10: Done. Please check if sufficient
Point 11: Line 182: please specify the default values. Furthermore delete “suggested by the software” and cite who or whose defined those values.
Response 11: The numbers have been included. However, we are not sure the criteria of the software to choose those values. We do have noticed that those default values give very good results when working with Sentinel-1 images but not so good when working with other sensors, such as TerraSAR-X. From this, we infer that those default values have been established for the spatial resolution of Sentinel-1 images. Please check if the explanation is enough.
Point 12: Line 182-183: have you published those previous experiences? Are there comparable with other studies? Please, clarify. The same for lines 188-189.
Response 12: Sorry, but those lines do not correspond to past experiences, I’m not sure which lines are you referring to. However, information about that has been included in lines 155-156.
Point 13: Line 271-273: “Once the processing of images until the creation” Consider rewriting this sentence.
Response 13: Done.
Point 14: Line 274: please specify “small size” with the specific value
Response 14: Done.
Point 15: Line 275: which past experiences? Have you published it?
Response 15: This part has been deleted.
Point 16: Line 289: I will suggest to briefly describe the number and type of combinations in the text.
Response 16: Done. Please check if it is enough.
Point 17 Line 332: consider citing after “its applicability”
Response 17: A reference has been added.
Point 18: Line 350-352: please consider rewriting “for those areas where doubts regarding the presence of fire were doubtful”
Response 18: Done.
Point 19: Line 377: delete and “color and while”. Revise English across the manuscript.
Response 19: Done.
Point 20: Line 424: please specify which variables
Response 20: I’m not sure of the request, the line number does not coincide with the numbering I visualize. I’ve searched the term “variable” and rewritten the sentence in which it appeared. Please check whether it is enough.
Point 21: Line 434-435: “even more” do you mean even though?
Response 21: No. Corrected.
Point 22: Line 440-457: the sentence that starts with “In all …” should be placed in the title of Figure 7. The authors should write at least a brief paragraph describing figure 7 (area in each classification, presence of small polygons, differences etc.). If a figure is not described is because it is not needed in the manuscript so either include a better description (desirable) or delete it. The description in figure 8 is much better for example.
Response 22: More information has been added explaining the figure. Due to the size of the figure, and trying to keep it in a single page, some parts of the manuscript have been moved.
Point 23: Line 476-477: do you create the classification using both sentinel-1 and the reference burned area created by Sentinel-2 data? Please clarify.
Response 23: I’m afraid the numbering of lines is different in my version. I have added some information right before the validation is explained, in the hope that will solve the doubt.
Point 24: Line 474: area of interest it is only described in the results but not in the methodology. Please include it in the methodology section as it is hard to understand the difference between OA and OAu. Furthermore Ou and Cu refers to the overall accuracy or to the AOI?
Response 24: Table 3, included in the methodology, explains the accuracy measures calculated. An explanation on why was the union of the burnt areas used to calculate the OA, the commission and the Omission is also explained.
Point 25: (from previous revision) Point 28: Discussion section should be considered rewritten there is no even one reference in discussion where the main aim of this part is compare with other results within the bibliography.
Response 28: The figure has been improved. Paging has been changed so four parts of the figure are in the same page.
Point 28 has only been partially addressed. There should be more references in the discussion and compare your results with the generated by other authors. For example in lines 520-522:
Best results were obtained using the combination of the MTC derived from Ascending and Descending modes together, independent of the polarization used (cite). This result seems to indicate that combining Ascending and Descending images minimises the effect of the topography (cite). Are these findings similar to other studies?.
Response 25: More information has been added. Please check if sufficient.
Point 26: (from previous revision) Point 29: Conclusion: you do not refer to your specific results founded in the paper. Paragraphs 2 and 3 are kind of general comments which can be either in the introduction or here but you really need to summarize your findings.
Response 29: The figure has been improved. Paging has been changed so four parts of the figure are in the same page.
This point has not been addressed. Specific results about the classification etc. should be included in the conclusion.
Response 26: More information has been added to the conclusions and throughout the manuscript. Please check if sufficient.
Point 27: (from previous revision) Point 30: The number of references is too short and most of them are not forest MDPI style. This should be increased along the paper specially within the introduction and discussion sections.
Response 30: The figure has been improved. Paging has been changed so four parts of the figure are in the same page
Please review carefully all the references at some of them are wrongly cited (see reference 1 as example) “Available under request…”?
Response 27: References have been reviewed.
