Climate Change and the Escalating Cost of Floods: New Insights from Regional Risk Assessment Perspective

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript covers an excellent topic that has significant importance these days. However, the following suggestions will be needed to incorporate to improve the manuscript's quality.

1. The title could be strengthened by specifying the case study region to highlight the novelty and regional focus, instead of keeping it too broad.
2. The introduction should cover the global as well as regional perspectives to discuss the background and literature review.
3. The introduction does not clearly identify the specific gap your study fills. Many studies link climate change to flooding, but what is unique about the Vipava basin case?
4. While RCP 2.6, 4.5, and 8.5 are mentioned, there’s limited explanation of how they were operationalized in the modeling framework. A short justification of why these scenarios and time horizons were chosen would improve transparency.
5. The integration of hydraulic modeling with the KRPAN model is mentioned, but its innovative aspect compared to previous methods isn’t emphasized. Is it the spatial resolution, regional application, or coupling with socioeconomic exposure data? This should be highlighted.
6. The introduction cites global-scale flood projection studies but could be improved by including regional and local references (Central European, Alpine, or Mediterranean catchments). This would position the Vipava valley case more strongly within regional flood research.
7. The study mentions planning and adaptive strategies, but the introduction could briefly outline existing flood protection measures in Slovenia/Italy, and how your results feed into improving or rethinking them.
8. In the end of the introduction section, discuss, Why Vipava is a critical test case (transboundary governance, history of floods, data availability). What your approach adds beyond previous studies (integrated modeling, detailed exposure data, scenario quantification). How the findings advance flood risk assessment frameworks under climate change.
9. Study area: Figure 1 should be provided with better description and revised maps. There are no Longitude, latitudes, and there are no clear understanding in Figure 1.
10. There should be a flowchart and a comprehensive paragraph to explain and describe the complete methodology/procedure adopted.
11. Figure 4: The color selection is not suitable, and it is mixing up all the findings. the colors for current, RCP4.5, and RCP 2.5 are almost similar.... 
12. Figure 4, There are two RCP 8.5.... it should be named differently, like in Figure 5.
13. At the end of results and discussion, you can add a paragraph where  Previous research works can also be discussed to place the findings in the broader context of existing literature, highlighting the consistencies and discrepancies, and providing a comprehensive perspective on how the current study’s results fit within the broader scientific discourse.
14. Add the limitations in the conclusions and future research directions. 

Author Response

The manuscript covers an excellent topic that has significant importance these days. However, the following suggestions will be needed to incorporate to improve the manuscript's quality.

We would like to express our gratitude to the reviewer for their valuable and constructive comments. For the purpose of addressing the comments made by the reviewer, please refer to the blue text below. The location of the changes made in the revised manuscript is indicated at the end of each reply.

 

Comment 1: The title could be strengthened by specifying the case study region to highlight the novelty and regional focus, instead of keeping it too broad.

Reply 1: We thank the reviewer for this valuable comment. We have revised the manuscript title in order to emphasize both its originality and its regional focus.

 

Comment 2: The introduction should cover the global as well as regional perspectives to discuss the background and literature review.

Reply 2: We have rewritten and expanded the Introduction to cover the global and regional impact of climate change on flood risk and damage. (Manuscript with changes marked, lines 32-34; 37-40; 48-50)

 

Comment 3: The introduction does not clearly identify the specific gap your study fills. Many studies link climate change to flooding, but what is unique about the Vipava basin case?

Reply 3: We thank the reviewer for this insightful comment. We have extended the Introduction section to point out the specific contribution of our research. We now more clearly introduce the specific characteristics of the Vipava River case study which strongly influence the flood risk and damage assessment. (Manuscript with changes marked, lines 71-73; 76-82)

 

Comment 4: While RCP 2.6, 4.5, and 8.5 are mentioned, there’s limited explanation of how they were operationalized in the modeling framework. A short justification of why these scenarios and time horizons were chosen would improve transparency.

Reply 4: We thank the reviewer for this helpful comment. In section 2.2 (Climate change driven changes in flood characteristics) we added information on the RCP scenarios and their consideration in the modelling framework. Slovenian Environmental Agency (ARSO) used three standard 30-year periods for climate change assessment 2011–2040 (the near future), 2041–2070 (the mid-century), 2071–2100 (the end of the century), aligned with international IPCC guidelines. (Manuscript with changes marked, lines 153-158; 168-171)

 

Comment 5: The integration of hydraulic modeling with the KRPAN model is mentioned, but its innovative aspect compared to previous methods isn’t emphasized. Is it the spatial resolution, regional application, or coupling with socioeconomic exposure data? This should be highlighted.

Reply 5: We extended the description on KRPAN model to highlight its innovative aspect. The KRPAN model's innovative approach to flood damage estimation lies in its integration of high-resolution spatial data from various databases, combining it with flood inundation data. The KRPAN model has a distinctly modular design and incorporates powerful external tools (e.g., SAGA and GDAL), intentionally avoiding higher-level programming languages when performing complex flood damage analyses. This allows the KRPAN model to estimate EAD for each vulnerability element (e.g., at the building level). (Manuscript with changes marked, lines 236-242)

 

Comment 6: The introduction cites global-scale flood projection studies but could be improved by including regional and local references (Central European, Alpine, or Mediterranean catchments). This would position the Vipava valley case more strongly within regional flood research.

Reply 6: According to the reviewer's comments, we have added references in the Introduction section that focus on the regional and local impact of climate change in Central European and Mediterranean catchments, due to the prevailing sub-Mediterranean climate characteristics of the Vipava river catchment. (Manuscript with changes marked, lines 48-51; 71-73)

 

Comment 7: The study mentions planning and adaptive strategies, but the introduction could briefly outline existing flood protection measures in Slovenia/Italy, and how your results feed into improving or rethinking them.

Reply 7: The introduction section was extended to introduce the existing flood situation in the lower Vipava river valley. The Results and Discussion section was supplemented with the discussion on incorporation of the study results into the early stages of flood mitigation measures planning. (Manuscript with changes marked, lines 76-84)

 

Comment 8: In the end of the introduction section, discuss, Why Vipava is a critical test case (transboundary governance, history of floods, data availability). What your approach adds beyond previous studies (integrated modeling, detailed exposure data, scenario quantification). How the findings advance flood risk assessment frameworks under climate change.

Reply 8: In line with the reviewer’s suggestions, the final part of the Introduction section has been extended. Now, we provide a more detailed introduction to the case study, considering the anticipated impact of climate change on flood risk and damage. (Manuscript with changes marked, lines 76-84)

 

Comment 9: Study area: Figure 1 should be provided with better description and revised maps. There are no Longitude, latitudes, and there are no clear understanding in Figure 1.

Reply 9: Figure 1 was revised according to the reviewer’s comments. The maps were revised, longitude and latitude/longitude labels were added.

 

Comment 10: There should be a flowchart and a comprehensive paragraph to explain and describe the complete methodology/procedure adopted.

Reply 10: We added a flowchart (new figure 4) that clearly represents the methodology adopted in the study. Some parts of the Materials/Methods (section 2.3 Hydraulic simulation and flood damage estimation) were rewritten to better describe the methodological framework. (Manuscript with changes marked, lines 207-217; 236-242)

 

Comment 11: Figure 4: The color selection is not suitable, and it is mixing up all the findings. the colors for current, RCP4.5, and RCP 2.5 are almost similar.... 

Reply 11: Figure 4 (new Figure 5) has been revised in accordance with the reviewer's comments. The color scheme was changed to provide a clearer representation of changes to the inundated area.

 

Comment 12: Figure 4, There are two RCP 8.5.... it should be named differently, like in Figure 5.

Reply 12: Thank you for bringing this to our attention. We have now corrected the legend for Figure 4 (new Figure 5).

 

Comment 13: At the end of results and discussion, you can add a paragraph where Previous research works can also be discussed to place the findings in the broader context of existing literature, highlighting the consistencies and discrepancies, and providing a comprehensive perspective on how the current study’s results fit within the broader scientific discourse.

Reply 13: We thank the reviewer for this comment. We expanded the final section of the Results and Discussion to better connect our study's results with the broader scientific discussion about the impact of climate change on flood risk and damage. (Manuscript with changes marked, lines 398-415)

 

Comment 14: Add the limitations in the conclusions and future research directions. 

Reply 14: Based on the reviewer's comments, we expanded the conclusion section to address potential limitations and suggest future research directions. (Manuscript with changes marked, lines 446-449; 452-456)

Reviewer 2 Report

Comments and Suggestions for Authors

 

The topic is timely, methodologically rigorous, and of clear policy significance. The paper is generally well-structured and written, with sufficient background to place the work within the broader literature. The use of a regional case study in a transboundary basin is valuable for both scientific and applied audiences. However, there are some areas where the manuscript could be strengthened—particularly in the presentation of uncertainty, methodological justification, and refinement of the discussion to highlight broader implications.

1. The paper acknowledges discharge variability but does not adequately discuss how uncertainties (hydrological input, climate scenarios, damage functions, socio-economic assumptions) propagate into the Expected Annual Damage (EAD). A section or subsection on sources of uncertainty and their influence on results should be added.
2. The hydraulic model (HEC-RAS) is mentioned as being calibrated against past floods, but no details are provided (fit statistics, validation events, error margins). A clear explanation of calibration datasets, methodology, and validation outcomes is needed.
3. It is not always clear whether the depth–damage functions and vulnerability data in the KRPAN model are Slovenia-specific or adapted from broader European datasets. The origin, reliability, and potential limitations of the damage functions should be explicitly described.
4. The text acknowledges that climate change undermines the meaning of “100-year floods,” yet return periods are still presented without consistent contextualization. The discussion on alternative risk communication (e.g., annual exceedance probability, design floods under non-stationarity) should be strengthened.
5. The manuscript would be stronger if it positioned the Vipava study within the broader European and Mediterranean literature. A comparative discussion should be added to show how the results align with or diverge from findings in similar basins.
6. Absolute terms like “absolutely flood safe” (e.g., Lines ~46, 343) should be replaced with more cautious wording such as “currently considered low-risk” or “protected under design conditions.”
7. Figures need clearer axis labeling and units (Figures 5–8). Scenario color schemes should be consistent. Numerical tables backing up figure data should be provided as supplementary material.
8. Several sentences in the Introduction and Discussion are overly long and reduce readability. These should be shortened for clarity.
9. Minor typographical errors should be corrected: “21th century” → “21st century”; “innundation” → “inundation”; “RCP 2.5” in Table 1 → “RCP 2.6.”
10. The conclusion mentions integration into spatial planning but could provide more actionable policy implications. Examples of adaptation pathways such as managed retreat, floodplain restoration, or green infrastructure could be added.
11. References need formatting consistency, with some abbreviated inconsistently. DOIs should be checked, and citation style aligned with journal requirements.

 

Author Response

The topic is timely, methodologically rigorous, and of clear policy significance. The paper is generally well-structured and written, with sufficient background to place the work within the broader literature. The use of a regional case study in a transboundary basin is valuable for both scientific and applied audiences. However, there are some areas where the manuscript could be strengthened—particularly in the presentation of uncertainty, methodological justification, and refinement of the discussion to highlight broader implications.

We would like to express our gratitude to the reviewer for their valuable and constructive comments. Please refer to the blue text below for our responses to the reviewer's comments. The location of the changes made in the revised manuscript is indicated at end of each reply.

 

Comment 1: The paper acknowledges discharge variability but does not adequately discuss how uncertainties (hydrological input, climate scenarios, damage functions, socio-economic assumptions) propagate into the Expected Annual Damage (EAD). A section or subsection on sources of uncertainty and their influence on results should be added.

Reply 1: We would like to thank the reviewer for this valuable comment. We expanded the Results/Discussion section to address the potential impact of uncertainty on the study's findings. We completely agree with the reviewer that uncertainties in the input hydrological data, climate change scenarios, and flood damage functions can significantly influence the results. The reliability of the study’s results is contingent upon the uncertainty of the input hydrological data, the appropriateness of the selected climate change scenarios, and the adequacy of the chosen flood damage functions. The present analysis addresses these uncertainties by considering a wide range of climate change scenarios. We believe that a scenario-based modeling framework helps to capture potential variability and the propagation of unknowns in flood risk and damage estimates, particularly in instances where the quantification of detailed uncertainty is challenging. Relatively small changes in input data can lead to significant differences in flood risk and damage estimates, underscoring the importance of scenario-based approaches in capturing the full spectrum of potential climate change impacts. (Manuscript with changes marked, lines 398-407; 446-449)

 

Comment 2: The hydraulic model (HEC-RAS) is mentioned as being calibrated against past floods, but no details are provided (fit statistics, validation events, error margins). A clear explanation of calibration datasets, methodology, and validation outcomes is needed.

Reply 2: We have added information on hydraulic model calibration in section 2.3 (Hydraulic simulation and flood damage estimation). The calibration of the hydrodynamic model involved adjusting the roughness coefficients for the river channel and floodplains to ensure that the simulated flood extents and water levels closely matched observed values. Validation was performed using data from several flood events, focusing on water levels at specific locations and inundation extents along several subsections of the Vipava River study area. (Manuscript with changes marked, lines 207-216)

 

Comment 3: It is not always clear whether the depth–damage functions and vulnerability data in the KRPAN model are Slovenia-specific or adapted from broader European datasets. The origin, reliability, and potential limitations of the damage functions should be explicitly described.

Reply 3: We have extended the description of the KRPAN model to more clearly present its structure. The flood depth-damage functions (FDF) were mainly taken from the extensive literature review (e.g. FEMA HAZUS-MH, Huizinga et al., 2017). Where data on flood damage from past flood events was available, site-specific FDF were derived. The data on the vulnerability elements are Slovenia-specific; the datasets include high-resolution spatial data from multiple sources, enabling detailed estimation of flood damage at a building scale and across diverse economic sectors. (Manuscript with changes marked, lines 236-242; 245-249; 254-258). Additionally, new Figure 4 was added to represent more clearly the flowchart of the methodological framework.

 

Comment 4: The text acknowledges that climate change undermines the meaning of “100-year floods,” yet return periods are still presented without consistent contextualization. The discussion on alternative risk communication (e.g., annual exceedance probability, design floods under non-stationarity) should be strengthened.

Reply 4: Thank you for this valuable comment. We have extended the discussion on risk communication in view of the changed annual exceedance probability due to anticipated climate change and potential consideration of design floods. (Manuscript with changes marked, lines 300-305).

 

Comment 5: The manuscript would be stronger if it positioned the Vipava study within the broader European and Mediterranean literature. A comparative discussion should be added to show how the results align with or diverge from findings in similar basins.

Reply 5: In order to position our study in broader Central European and Mediterranean context, we have extended the Introduction section and discussion in section 3.2 (Estimated flood damage for climate change scenarios), we added references that investigated the impact of climate change on floods in these regions. (Manuscript with changes marked, lines 37-40; 48-51; 350-356)

 

Comment 6: Absolute terms like “absolutely flood safe” (e.g., Lines ~46, 343) should be replaced with more cautious wording such as “currently considered low-risk” or “protected under design conditions.”

Reply 6: We would like to thank the reviewer for this notion. We have rephrased several sentences by using more cautious wording regarding “absolute” flood safety. (e.g. Manuscript with changes marked, lines 56, 372-375; 425)

 

Comment 7: Figures need clearer axis labeling and units (Figures 5–8). Scenario color schemes should be consistent. Numerical tables backing up figure data should be provided as supplementary material.

Reply 7: Figures 5-8 (new Figures 6-9) were corrected and modified according to the reviewer’s suggestions; scenario color schemes were unified. We have decided not to include the numerical tables as supplementary material. However, we can provide all the numerical results upon request.

 

Comment 8: Several sentences in the Introduction and Discussion are overly long and reduce readability. These should be shortened for clarity.

Reply 8: Following the comments and suggestions of different reviewers, several sentences in the introduction section and Results/Discussion section were rewritten and shortened to make the text clearer and more concise.

 

Comment 9: Minor typographical errors should be corrected: “21th century” → “21st century”; “innundation” → “inundation”; “RCP 2.5” in Table 1 → “RCP 2.6.”

Reply 9: We would like to thank the reviewer for these careful corrections. We have revised the text and corrected the typographical errors.

 

Comment 10: The conclusion mentions integration into spatial planning but could provide more actionable policy implications. Examples of adaptation pathways such as managed retreat, floodplain restoration, or green infrastructure could be added.

Reply 10: We have extended the Conclusion section to address the possible alternative policy implications and adaptation measures suggested by the reviewer. (Manuscript with changes marked, 411-415; 452-456)

 

Comment 11: References need formatting consistency, with some abbreviated inconsistently. DOIs should be checked, and citation style aligned with journal requirements.

Reply 11: We would like to thank the reviewer for these careful corrections.  The references formatting was checked and corrected according to journal requirements.

 

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

The paper presents a comprehensive study on climate change and the escalating cost of floods from risk assessment perspective. It is a topic of interest to the researchers in the related areas but this article has some details that need to be revised before acceptance for publication.

1. The white box in the upper left corner of Figure 1 is not necessary.
2. Line 209 ‘innundation’ spelling mistake ;
3. Table 1 , RCP 2.5 should be RCP 2.6?
4. Figure 4 , The legend does not make a distinction about RCP 8.5 (I) and RCP 8.5 (II), and What is the difference between RCP 8.5 (I) and RCP 8.5 (II)? Please provide a detailed explanation.
5. Figure 5, vertical axis ‘innundation’ spelling mistake ; RPC 4.5 should be RCP 4.5?

Comments on the Quality of English Language

This article has met the standards for publication.

Author Response

The paper presents a comprehensive study on climate change and the escalating cost of floods from risk assessment perspective. It is a topic of interest to the researchers in the related areas but this article has some details that need to be revised before acceptance for publication.

We would like to express our gratitude to the reviewer for their valuable and constructive comments. Please refer to the blue text below for our responses to the reviewer's comments. The location of the changes made in the revised manuscript is indicated at end of each reply.

 

Comment 1: The white box in the upper left corner of Figure 1 is not necessary.

Reply 1: We would like to thank the reviewer for the comment. We modified Figure 1 in order to make it clearer. We decided to keep the map of Slovenia because other reviewers emphasized the importance of a clearer geographical representation of the study site. 

 

Comment 2: Line 209 ‘innundation’ spelling mistake.

Reply 2: Thank you for this remark, the text was thoroughly revised for English spelling and grammar. Several grammar corrections were made including the ones mentioned by the reviewer.

 

Comment 3: Table 1, RCP 2.5 should be RCP 2.6?

Reply 3: Thank you for this remark, we have corrected the RCP2.6 scenario in Table 1.

 

Comment 4: Figure 4, The legend does not make a distinction about RCP 8.5 (I) and RCP 8.5 (II), and What is the difference between RCP 8.5 (I) and RCP 8.5 (II)? Please provide a detailed explanation.

Reply 4: We would like to thank the reviewer for this insightful comment. Figure 4 was revised according to the reviewer’s comments. The color scheme was changed to more accurately represent changes in inundated areas. Additionally, the legend was revised for clearer distinction between the RCP 8.5(I) and RCP 8.5(II) scenarios. We provided additional explanation about the scenarios considered (Manuscript with changes marked, lines 153-159) and the differences between the two extreme scenarios in section 2.2 (Climate change driven changes in flood characteristics). (Manuscript with changes marked, lines 168-171)

 

Comment 5: Figure 5, vertical axis ‘innundation’ spelling mistake; RPC 4.5 should be RCP 4.5?

Reply 5: We would like to thank the reviewer for this correction, we have revised the spelling and corrected the y-axes of Figure 6 in the revised manuscript (old Figure 5).

 

Author Response File: Author Response.docx

Reviewer 4 Report

Comments and Suggestions for Authors

The paper deals with the risk assessment related to floods in the Vipava River catchment considering climate change.

The authors made an arbitrary estimation of the expected increases of the discharge peaks of the Vipava river of 5, 10, 20 and 40% for scenarios 2.6, 4.5, 8.5 (I) and 8.5 (II).

Those expected increases are the same for return periods from 5 to 500 years for a given scenario of climate change.

With those increased discharges, they obtain the flood maps using 2D hydraulic simulation with a 48-h SCS design hydrograph.

The authors made 24 simulations for 6 return periods and 4 climate change scenarios.

They compute the expected annual damage for 24 results and then they conclude what is stated in the abstract and conclusion sections.

From my point of view, no new contributions are made with the work presented in this paper, apart from demonstrate the increasing cost of floods with the increment of the discharge peak related to the climate change in a given catchment of Slovenia.

Also, I believe that the expected increases of 5 to 40% in the discharge peaks are totally arbitrary and might not reflect the real behaviour of the hydrological response considering climate change in Slovenia.

I propose the authors estimate the increasing of the rainfall due to the climate change and then make a rainfall-runoff transformation to have better estimation of the discharge peak increase.

 

 

Minor issues

1. 112: please, try to insert the caption of Figure 2 in the same page of the Figure.
2. 190: please, correct the number of simulations made, if it is the case.

Author Response

The paper deals with the risk assessment related to floods in the Vipava River catchment considering climate change.

The authors made an arbitrary estimation of the expected increases of the discharge peaks of the Vipava river of 5, 10, 20 and 40% for scenarios 2.6, 4.5, 8.5 (I) and 8.5 (II).

Those expected increases are the same for return periods from 5 to 500 years for a given scenario of climate change.

With those increased discharges, they obtain the flood maps using 2D hydraulic simulation with a 48-h SCS design hydrograph.

The authors made 24 simulations for 6 return periods and 4 climate change scenarios.

They compute the expected annual damage for 24 results and then they conclude what is stated in the abstract and conclusion sections.

From my point of view, no new contributions are made with the work presented in this paper, apart from demonstrate the increasing cost of floods with the increment of the discharge peak related to the climate change in a given catchment of Slovenia.

 

We would like to thank the reviewer for his comments. Please refer to the blue text below for our responses to the reviewer's comments. The location of the changes made in the revised manuscript is indicated at end of each reply.

Reply 1: We have thoroughly revised the manuscript to highlight the detailed regional implications of the study by using detailed results of hydraulic modelling and high-resolution flood risk and damage estimation by application of innovative KRPAN methodology. We believe the innovative aspect of our study lies in the specific characteristics of the case study and integration of high-resolution spatial data from multiple sources which strongly influence the flood risk and damage assessment. This integration enables us to make detailed estimates of flood damage at detailed spatial scales (e.g. at the building scale) and across diverse economic sectors. The KPRAN model combines hydraulic simulation outputs with comprehensive exposure databases to provide a locally tailored assessment of flood risk and damage, surpassing the limitations of conventional, coarse-resolution approaches. (Manuscript with changes marked, lines 76-83; 235-241; 253-257; 349-355; 397-406)

 

Also, I believe that the expected increases of 5 to 40% in the discharge peaks are totally arbitrary and might not reflect the real behaviour of the hydrological response considering climate change in Slovenia.

Reply 2: Thank you for this comment. We would like to point out that the increases of flood peaks were not made arbitrarily by the authors of the paper. The expected impact of climate change on flood peaks was based on official Slovenian Environmental Agency (ARSO) study on the Assessment of climate change in Slovenia until the end of the 21st century. In section 2.2 (Climate change driven changes in flood characteristics) we added information on the RCP scenarios and their consideration in the modelling framework. ARSO considered three standard 30-year periods for climate change assessment 2011–2040 (the near future), 2041–2070 (the mid-century), 2071–2100 (the end of the century), following IPCC guidelines. Therefore, we believe that the considered scenarios well cover the potential span of the future impact of climate change on flood peaks, from the optimistic to the worst-case scenarios. (Manuscript with changes marked, lines 153-158; lines 168-170)

I propose the authors estimate the increasing of the rainfall due to the climate change and then make a rainfall-runoff transformation to have better estimation of the discharge peak increase.

Reply 3: We would like to thank the reviewer for this comment. It is crucial to emphasize that the repercussions of climate change have been determined through the utilization of regionally adapted climate models. These models were calibrated by using the official Slovenian Environmental Agency measurements from the 1981-2010 period, to minimize the discrepancy between the simulated and actual climatic conditions. The models have been employed to predict the anticipated variations in temperature and precipitation associated with the selected climate change scenarios. The data obtained from these models have been integrated into the hydrological model NAM (a part of part of the MIKE HYDRO Basin) to simulate peak discharges. In the revised manuscript, we have expanded the description of the considered climate scenarios and their impact on floods to ensure a more comprehensive representation of the hydrological input data in hydrodynamic modelling. (Manuscript with changes marked, lines 153-158; lines 168-171)

 

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Study area: Figure 1 is still not up to the mark, and it should be provided with a better description and revised maps. Currently, there is no clear understanding in Figure 1. Write the name of the country, neighboring countries, regions, places, etc.... 

Overall, the authors have incorporated all the suggested changes and the manuscript is now suitable for publication after the change in Figure 1. 

Reviewer 4 Report

Comments and Suggestions for Authors

Good work!